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Hotel-de-Ville, at Ypres, has a spire clustered with four of very large pinnacles or small spires of tabernacle charac. exceedingly tall pinnacles or lesser spires. Where there ter. Cambrai and Esslingen on the Neckar afford other are windows placed against a spire, rising upright like examples of ope:s-work spires. the dormers or lucarnes on a roof, the term Lucarned There are various other circumstances which, tlough would express that character; we have therefore not scru- they do not affect the spire itself, produce greater or less pled to make use of it in the annexed table of spires, where difference in regard to the character of the structure of it is applied, among others, lo those of Lichfield cathedral, which it is a component feature. Very much, for instance, which have several tiers of such windows, and are described depends upon its situation in the general plan: at Salisbury, accordingly. Crocketted and Banded are terms requiring Norwich, and Chichester, the spire is raised upon a tower no explanation; but in regard to the first it may be remarked, at the intersection of the cross, or in the centre of the plan; that spires, otherwise quite plain, are sometimes ornamented whereas in most continental cathedrals and large churches with crockets along their edges; and with respect 10 bands, there are two spires on the towers of the west front, though they are sometimes little more than string-mouldings, but in in some instances (Strassburg, Antwerp) only one has been other cases broad and enriched surfaces. Many of the spires erected. Several however have a single rower and spire in in Normandy are ornamented with such a number of bands, the centre o! the west front (Ulm, Freyburg, Thann in that they form alternating courses with the plain spaces be. Alsace), in which case the tower itself begins to diminish tween them. Finianed is a term which does not apply to almost from the ground, and the whole becomes what we any of our English spires; but that of St. Stephen's, have described as of the tabernacle character. in most of Vienna, and some other continental spires, have an exceed- our English churches (not cathedrals) the spire is placed ingly large and rich finial, which ornament gives them a upon a tower at the west end, as at Grantham, Louth, particular boldness of expression. The Tabernacle-spire Bloxham, &c. If we except Peterborough, where they are also is one of which there is no example in this country, very diminutive, the only English cathedral which has two but of which the one just mentioned, and those of Strassburg, western spires is Lichfield, which is further remarkable as Ulm (as designed), Thann in Alsace, and many others, are having a central tower and spire also. Besides the richiness specimens, the lower and spire being carried up from the and variety thus produced, the larger central spire serves to ground in a succession of diminishing stages, all profusely balance the whole compositioli, whereas else the body of the adorned with panneliing, niches, canopies, pinnacles, and structure is apt to look low in comparison with the west end. other tabernacle-work, in such a manner that it is barely At St. Stephen's, Vienna, the tower and spire are singularly possible to distinguish where the upright portion or tower placed on the south side of the edifice, it having been interminates, and the spire itself begins, the latter seeming iended to balance them by a corresponding tower on the little more than the uppermost stage in continuation of the north side. At Gelnhausen, on the contrary, there is a group rest. Neither have we any instances of Open-work spires, of spires, as already noticed, at the east end. or of such as, if not actually perforated, are yet entirely Although the building itself is by no means a tasteful covered with tracery. That at Freyburg, and those at example, the façade being in a rude and plain Norman Burgos and Batalha, are all exceedingly rich specimens of design, the annexed view of St. Stephen's at Caen will the kind. The chapter-house of Burgos also has a series / assist in explaining some of the preceding observations.

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We have here two vestern towers and spires, which last nominated cluster-based, the turrets with their smaller sre not parapeterd, but merely embased with turrets and stump-spires being clustered around the larger one. These pinnacles at their angles, rising up to a considerable spires are also lucarned below and banded; although in the height; consequently they answer to what we have de- I cut those circumstances are rather indicated than expressed.

One circumstance plainly observable is that the whole rest than the other; being in the ratio of 163 to 308 feet, façade is of narrow proportions, and the space between while Salisbury is only 197 to 404. We have iberefore the towers very small. The spires themselves are short, drawn up a table of spires, showing the separate as well a; both in proportion to their own diameters and to the height united heights of the respective towers and spires ; and of the towers, which are carried up so high as to appear although in some instances we have been unable to obtała very lofty as compared with the rest of the structure. those dimensions, the table supplies Other information in re

Though so much depends upon circumstances of this kind, gard 10 the examples mentioned in it, and will at least serre almost the only thing that is specified in the usual description as a model for a more complete list of the kind. In addition of spires is the entire altitude from the ground, which single to it we will here briefly enumerate some of the examples measurement, unaccompanied by others, gives no idea of the arranged according to the proportions of the spires, or their relative dimensions of the spire or how it is proportioned. heighis as measured by the diameters of their bases : Siz Some of the loftiest spires, as they are populariy termed, diarneters in height, or more than five, old St. Paul's; are by no means lofty, being not above a third of the entire St. Stephen's, Vienna; Norwich ; Five, or more than four, height, and not more than four of their own diameters. Salisbury, Bloxham, Marburg (41); Four, St. Mary's, OxThe spire of Strassburg, for instance, is only 110 feet out of ford (nearly), Glasgow (do.), Ulm (do.), Bayeux (ratber 474, or less than one-third of the tower itself. At Ant-more), St. Stephen's, Caen; Freyburg (rather less); si werp again the spire is a mere peak crowning the upper- Peter's, Caen; Three, or more than two, St. Mary's. Stammost stage of the tower, while the tower itselp is twice as ford; Welford ; Strassburg; Batalha : Two, Oxford catbehigh as the roof of the church. If we compare Salisbury dral; small western spires, St. Stephen's, Vienna. One, with Norwich, the spire of the latter cathedral will be found, Worms, Gelnhausen. though of less dimensions, much loftier in relation to the

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534 Six diameters high.
404 Date about 1350. Three enriched bands. Nearly five diameters.
303 Plain, rather more than five diameters high.
252 Lucarned, 5 tiers of windows. Nearly 5 diameters high.
192 Lucarned, 4 tiers; 4; diameters high.
270 Pinnacled and lucarned below; banded with one broad rich band;

else quite plain.
146 Date about 1220.
180 Spire itself quite plain, lucarned with a canopied window below, on

four sides. Embased by very rich canopied niches and pinnacles. 288 Embased with lofty pinnacles and flying buttresses. Crocketted.

6 diameters. 250

Lucarned, crocketted, large crocketted pinnacles at base. Base of

spire less than tower. Short spire, spreading out at its base. Lucarned, with 4 tiers of win

dows. 195 A very beautiful example. Spire 5 diameters high. Date about 1350 300 This tower and spire a very fine example.

Date about 1260. Base without parapet or pinnacles. Lucarned,

4 tiers. Spire 2} diameters. An example of a spire on a low circular tower. Lucarned at its base

with lofty gabled windows. Spire 3 diameters. 150 Two west lowers, only N.W. spire yet erected. (Comp. to Almanak,

1842.) 530

Two west spires enriched with tracery, and crowned by large finials. 474 Two west towers, only N.W. spire. 465 On south side of church. Example of a tabernacle tower and spire. 491

Tabernacle example. Tower and spire in centre of west front. 380 Rich open-work spire. Tower and spire in centre of west front. 212 Two west towers and spires. Base of spire gabled. Spire 4} diameters. 270 .Do.

do.

do. 260 Do.

do.

do.
A tabernacle example, with rich tracery-work on spire. Spire about

one-fourth of entire height.
366 Two west towers, only N.W. spire.

Two west spires, the N.W.one loftier and more enriched than the other. 246 Two west spires. The north-west spire has 6 broad bands; the other

plain. Diameter at base 27 feet. 262 Lucarned at base and banded. 244 Base of spire 24 feet. Spire has 9 bands, with small hexa foil, quatre

foil, and trefoil apertures between them. Crocketted. 170 Very rich open-work spire. Diameter at base 19 feet.

Two short or stump but rery rich open-work spires, at west end.

Date of spires 1442. 220 Lucarned, banded, lower band richly moulded and quatrefoiled, and

surmounted by theurons. Diameter at base 27 feet. 239 A new church, finished 1831. Lassaulx, architect. Spire, a broach,

splayed off at base. Diameter, above splay, 16 feet; height about

8 diameters. 280 Church erected by Ohlmuller; completed 1839. Spire an open-work

helm or broach.

330 364 285 320 221 184 180 170

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SPIRES. [SPEYER.]

to most substances capable of being vaporized and con SPIRIT, in Chemistry. This word, especially when em- densed by distillation, and to some not obtained by distillation. ployed by itself, is now almost exclusively applied to spirit of It will be requisite merely to name a few of those compounds wine, or alcohol; formerly however the word spirit was given I to show how extensively it was used and misapplied to sub

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stances of very different origin and composition: thus nitric and the following is the usual manner of performing the acid was calleil spirit of nitre; hydrochloric acid, spirit of adjustments, preparatory to the instrument being employed salt; sulphuric acid, spirit of sulphur; chloride of tin, spirit on the ground:-of Libavius; solution of ammonia, spirit of sal-ammoniac, The ielescope should, by a proper opening of the legs of and so forth.

the staud, be at first rendered as nearly level as can be estiSPIRIT-LEVEL, a tube of glass nearly filled with spirit mated by the eye; then, being turned so as to lie vertically of wine or distilled water, and hermetically sealed at both above the line joining two opposile screws in what are called ends, so that when held with its axis in a horizontal po- the parallel plates (K and L), the spirit-tube is brought to sition, the air whieh occupies the part not filled with the a horizontal position by relaxing the screw nearest to its spirit or water places itself contigucusiy to the upper sur higher end, and tightening that which is opposite to it: the face. The tube being supposed to be perfectly cylindrical, like operation is to be performed with the other pair of the exact horizontality of its axis is ascertained by the ex- screws, after placing the telescope vertically above them. tremities of the air-bubb.e ceing at equal distances from In order to render the spirit-tube parallel to the axis of the the middle point in the length of the glass.

telescope, after the bubble of air has been made to occupy The spirit-tube is used in determining the relative heights the middle place by the process just mentioned, let the of ground at two or more stations, and in order to render it telescope be reversed in the arms (the Ys, as they are available for this purpose, it is placed within a brass case called); then, if the bubble does not still occupy the middle, having a long opening on the side which is to be uppermost, it must be made to do so by successive trials, endeavouring and is attached to a telescope; the telescope and tube are to correct half the error by means of the screw b, and the then fitted to a frame, or cradle, of brass, which is supported other half by the screw G. on three leys. In the interior of the telescope, at the com The eye-piece of the telescope must be moved inwards or mon focus of the object-glass and eye-glasses, are fixed, outwards till the wires in the field of view are distinctly generally, two wires, at right angles to each other, their in- seen; and the object-glass must also be moved by means of tersection being in the line of collimation, or that which the pinion, M, till the station-staff, placed at any convenient joins the centres of all the lenses.

distance (suppose 100 yards), is also distinctly seen. By a few trials, the distance between the eye and the object-glass may be made such that the intersection of the wires will appear to remain constantly at one point on the staff while the observer in looking through the telescope varies the position of his eye. It is necessary besides that the intersection of the wires should be precisely in the line of collimation, or the optical axis of the telescope: for this purpose the point of intersection should be directed to some well-defined mark at a considerable distance. The telescope must then be turned on its axis; and if the intersection remains constantly on the mark, that adjustment is complete; otherwise it must be rendered so by means of the screws, c, d, &c., on the lelescope ; those screws being placed at the extremities of two diameters at right angles to one another, on being turned they move the plate carrying the wires in the directions of those diameters. In order that the correction may be made, the apparent displacement of one of the wires, in consequence of the telescope being

turned half round on its axis, should be observed, and the The case containing the spirit-tube is made to turn on a screws turned till half the displacement is corrected; the joint at one extremity, as a, by the revolutions of a screw, like observation and correction may then be made for the b, at the opposite extremity; and the telescope rests, near other wire: a few repetitions of each adjustment will próeach end, within two arms at the top of a small pillar, A or bably be necessary before the error is wholly removed. B, the pillar and its arms resembling the letter Y, and the The level constructed by the late Mr. Troughton differs interior sides of the arms being tangents to the tube of the from that which has been above described in having the telescope. One of these pillars is made capable of a small spirit-tube sunk partly in the telescope; and the latter, movement in a vertical direction by turning a screw, C, at being incapable of a movement about its axis, doos not its base, for the purpose of elevating or depressing one end admit of a separate adjustment for the intersection of the of the telescope and spirit-tube; and in the more perfectly wires. constructed instruments, both the pillars may be so moved. Mr. Gravat, who has within a few years made consiThe pillars are at the extremities of a strong brass plate, derable improvements in the mechanisin of these instruEF, the under side of wbich is connected with the tripod ments, recommends the following method by which the stand, which supports the whole instrument; and a compass- error in the positions of the cross-wires and spirit-tube may box, G, is attached immediately to the plate, as in the cut, be ascertained and corrected :or is raised above the telescope by means of four small pil Let three pickets be driven into the ground in a line and lars. A hollow conical socket, H, of brass is screwed to at equal distances from one another, and let the spirit-level the under side of the plate, and is intended to receive a be set up successively in the middle between the first and piece of bell-inetal of a corresponding form, which consti second, and between the second and third pickets; then, tutes the upper part of the stand. This piece serves as a having by the screws of the instrument adjusted the spiritvertical axis, upon which the telescope, the spirit-level, and tube so that the buibic of air may retain the same place the compass are to turn round horizontally: sometimes while the telescope is turned round on the vertical axis

, however ihe conical pivot projects from the under part of direct the object-end of the telescope successively to the the plate, EF, and the socket is on the stand.

station-staves held up on the different pickets, read the The three legs which are to support the instrument are several heights, and take the differences between those on firmly fixed to a circular plate, K, perforated at its centre, the first and second, and on the second and third staff. and having about the perforation a hollow spherical zone, Now the staves being at equal distances from the instruresembling a small inverted cup. In the simpler kinds of ment, it is obvious that any error which may have existed spirit-levels a circular plate, L, of the same dimensions as in the line of collimation, or from the spirit-tube not being the last, carries above it the pivot before mentioned; and parallel to that line, will be destroyed, and the differences from below it projects a stem, terminating in a ball, which between the readings on the staves are the differences in fits the inverted cup or socket. By means of four screws the levels of the heads of the pickets; but unless the adwhich pass through one of these two plates (the upper plate justments are perfect, this will not be the case if the instruin the cut), nearly at the extremities of two diameters at ment be set up at any point which is unequally distant right angles to one another, the upper plate is made parallel from all the pickets; therefore from such point direct the to the horizon, and consequently the conical pivot which it telescope to ihe staves, and take the differences of the carries is brought to a vertical position.

readings as before. On comparing these differences with The above is a general description, which will sorve nearly the former, a want of agreement will prove that the interfor every spirit-level at present in use, whatever b: its form; section of the wires is not in the optical axis; and the error

may be corrected by means of the screws belonging to the SPIRU'LIDÆ, Professor Owen's name for a family of wire plate. After the agreement has been obtained, should polythalamous, decapodous, dibranchiate CEPAALOPODA the bubble of air not stand in the middle of the tube, it may ihus characterized by bim :be brought to that position by the screw b, at one extremity Animal corresponding in external form to the Decapaof the case, and the instrument is then completely adjusted. dous type; internal organization unknown, presumed to be (Simms, Treatise on Mathematical Instruments.)

Dibranchiate. Shell partly internal; cylindrical, multiloThe spirit-level is usually provided with a clamp, N, and cular, discoïd; the whorls separated; septa transverse, con a screw, P, by which, when the axis of the telescope has by care next the outlet, and wiih regular intervals. Siphon hand been brought near the object, the coincidence may be marginal and internal, uninterrupied. accurately made by a slow and steady motion about the Genus SPIRULA, Lam. vertical axis.

The character of the family is also that of the single The spirit-tube or level which is employed for the adjust- genus of which it is at present composed. ment of transit telescopes or astronomical circles is con Example, Spirulu Australis, Lam. tained in a case with feet or with loops at jis extremities, M. de Blainville, who, in the first volume of the Nouvelles in order that it may either rest above or be suspended below Annales du Museum (1835), had given a detailed account the horizontal axis of the instrument to be levelled; also of the anatomy of the shells of Nautilus Pompilius and the upper part of the case is furnished with a graduated Spirula, with coloured figures, has since published in scale, the divisions of which are numbered on each side of a the Annales Françaises et Etrangères d'Anatomie et de zero point, this point being usually placed near each of the Physiologie appliquées à la Médicine et d l'Histoire Na. two extremities of the air.bubble when the tube is in a hori. ture'le, his observations Sur l'Animal de la Spiruie, el sur zontal position. Having set up or suspended the spirit-tube, l'usage du Siphon des Coquilles polythalames. His account the iwo particular graduations at which the extremities of is founded on dead specimens, more or less complete, 'the the air. bubble rest are marked; and half the sum, or half remains, doubtless, of the voracity of fishes,' which he owed the difference of these numbers, according as the extremities to the perseverance of MM. Leclancher and Robert, who of the bubble are in the same or in opposite directions from collected them as they floated dead on the surface of the the two zero-points, being taken, gives the distance of the Atlantic, near the western coast of Africa. centre of the bubble from the middle between those points.

In the last-named memoir, M. de Blainville refers to the The level being then reversed, the graduations at which the former one as having placed beyond doubt, as it seems to him, air-bubble rests are again marked, and half the sum or half the very complex com position of the siphon of the shell,‘que,' the difference is taken as before. A mean of the two dis- says he, j'ai montréâtre formé d'une suite de petits entun. tances thus found is the true distance of the centre of the noirs s'emboitant plus ou moins les uns dans les autres, le bubble from the middle point on the scale; and the screw manière quelquefois à former un tout solide, mais aussi which elevates or depresses one end of the axis of the tele- quelquefois ne se touchant pas, et alors les intervalles scope being then turned, till either extremity of the bubble étant remplis par une partie membraneuse encrouiée d'une has moved, in a direction contrary to that in which the couche calcaire, de telle sorte que, même dans ce dernier centre of the bubble had mored from the middle of the cas, la partie charnue provenant de l'animal ne peut jamais scale, through a number of divisions equal to that mean être à nu dans les loges qu'elle traverse.' He adds, that he distance, that axis will be brought to a horizontal position. had concluded from this anatomical disposition that this peThis method is used in preference to that of successive culiarity of appearance in the siphon was nothing else iban trials, in order to avoid the trouble of making several rever a mode of attachment of the animal to its shell, a sort of sions of the whole instrument.

muscular insertion by a tubular prolongation, not continuThe levelling-staff till lately in general use for finding ing itself probably throughout the length of the siphon of the relative heights of ground is a rod cunsisting of two the shell. : Voyons,' he continues, - si mes conjectures parts, each six feet long, which, by being made to slide on étaient fondées en étudiant aujourdhui ce que je possède de one another, will indicate differences of level nearly as great l'animal dont elle fait partie, c'est-à-dire, je le répèle, le as twelve feet. The face of the rod is divided into feet, tronc dont la tête et les bras ont été arrachés.' inches, and tenths, or into feet with centesimal subdivisions; M. de Blainville describes the animal of the Spirula, and a vane, or cross-piece of wood, perforated through the limited by the mantle, as in the form of a long case, very middle, is moved up or down upon the rod by an assistant regularly symmetrical, of an oval shape, slightly compressed till a chamfered edge at the perforation is seen by the ob- at the sides, narrower and more circular forwards, and more server at the spirit-level to coincide with the horizontal elevated and more compressed backwards. The anterior wire in the telescope. The height from the ground to the extremity presents a sufficiently regularly trilobated aperchamfered edge of the vane must be read by ihe assistant; ture, there being one median lobe a little longer above, and and it being out of the power of the observer to detect any two lower lateral lobes a little more pointed and separaled mistake in the reading, it becomes very desirable that the by a median fissure below. This orifice is constituted by graduations on the rod should be sufficiently distinct to the borders of the mantle or of the sac of the Sepiaceans, allow the heights to be read at the spirit-level itself. The the collar of the Siphobranchians forming here a consirod proposed by Mr. Gravat for this purpose is divided into derable case, in which the head and its appendages can hundredths of a foot by stripes which are alternately black enter and be completely sheltered, a little like the slugs and white, and are numbered at every foot in the usual way (limaces) under their buckler. The trilobated form of this with figures great enough to be seen on looking through aperture recals, observes M. de Blainville, sufficiently well the telescope; the tenths of a foot are indicated by lines that which is at present known respecting that of many longer than the others. A similar staff has been proposed ammonites. The posterior extremity of the sac or mantle by Mr. Sopwith and Mr. W. P. Barlow; and the former convex (renflée) and widened vertically (a disposition which gentleman, besides the number of every foot, has given a is principally due to the shell solidly and vertically encased number to every first, third, fifth, and ninth decimal. Mr. in the skin) presents, entirely, behind a sort of oblique Barlow's rod is also divided into centesimals of a foot; but thatness (aplaiissement), at the middle of which is a ferthe marks, instead of being stripes whose edges are parallel minal button, accompanied on the right and left by a small to one another, hare the form of triangles : each tenth semicircular fin, attached by the right border, and very like mark however is in the form of a lozenge, or double triangle, that wbich exists in Sepiolu. Tlus mantle or case, in its for the sake of greater distinctness.

anterior moiety at least, has, besides, an anatomical strucSPIRIT-TRADE. (WINE AND Spirit TRADE.] ture, which brings to remembrance what exists in the Cala SPIRIT of WINE. [ALCOHOL.]

maries, that is to say, it is formed of a contractile very SPIROGLYPHUS, a genus framed for a species of Ser: thick lamina or derm constituting the principal part, offer pula of authors, which makes a groove for itself upon and ing on its surface a great number of lacunæ, forming a in the surface of shells. (TUBICOLIDE.]

net; of a nacreous layer on which is the part coloured by SPIROLI'NA. (FORAMINIFERA.]

small spots, violaceous, doubtless, during life, as in the SPIROLOCULINA. [FORAMINIFERA.]

Sepiolæ ; and, lastly, of a sort of epidermic varnish or SPIRO'RRIS, Lamarck's name for a genus of Serpula glazing, only the contractile part is perhaps still more solid, of authors; the white little shell is coiled round into a spiral and capable of more resistance than it is in the calamaries. disc-like form. Common on the shell of lobsters. [TUBI But in lieu of being sustained in the back by a cartılaginous COLIDÆ.]

or calcareous nearly straight lamina, it contains a shell, SPI'RULA. [SPIRULIDB.]

whose very much elongated and very regular spiral cone

presenting its base open in front, is rolled up vertically | itself to the siphon of the first chamber, and then continue backwards behind and below, in coils which are concentric, ing itself without any adhesion, as M. de Blainville supposes, but disjoined, or not contiguous. This shell is no more up to its origin towards the summit of the shell; from which really external in any of its points than the cartilage of the he was able in fact to withdraw it withoui breaking it for a calamaries, or the bone of the cultles. Only fastened ou considerable length; so that it may be said that this is in a the back and belly in the circumference of a small elon prolongation of the columellar or retractor muscle of the gated oval space by the dermomuscular layer, and, as it head and its appendages, and that the membranous siphon were, set in it, it forms a sort of hernia, and is not covered itself is only a part of this muscle. in these two places, except by the superficial parts of the The manile, ihe envelope of the shell, and the mass of the skin, the nacreous and coloured layers. Wiih regard 10 viscera, afforded the following analysis: tbe rest of the spire, it is contained in a subdermic space, The shell, entirely free in the dermoid envelope which occupying the posterior part of the visceral mass, which is contains it, has not its terminal excavation augmented in perfectly independent of it, veing separated from it by a depth by a rather considerable membranous border, as M. subcutaneous membrane, which is very delicate, but as de Blainville had supposed in his anatomy of the shell; it distinct as in the sepiaceans. This space or lacuna is, is only lined by the membranous hood already described, at nevertheless, traversed by a bridle equally dermic, which the circumference of which terminates anteriorly the fascia passes from one wall to the other, across the disjunction of of the columellar muscle, and, behind, the subdermic mem the whorls.

brane which forms the chamber of the shell. Placed in the Before he examines the relations of the shell with the back of the animal, this first chamber contains no viscus membranous siphon proceeding from the animal, M. de either in whole or in part; and very certainly the memBlainville iurns his attention to the mode in which the branous siphon has no connexion except with the fleshy visceral mass is disposed. Sufficiently considerable, espe- hoorl, and none whatever with the peritoneal cavity, at the cially at the period when the generative apparatus is in a anterior and lower part of which M. de Blainville states that state of turgescence, it occupies the whole bottom of the he could easily recognise the beart receiving the branchial cavity of the mantle, prolonging itself more or less on each vessels, which are very long on account of the advanced side of the subdermic envelope, which includes iho shell, position of the branchiæ. behind the excretory funnel, situated under the neck, as in M. de Blainville then observes that the very exact dethe other sepiaceans, and between the two branchiæ, situ. scription, as he hopes, thus given of the principal parts of ated one on the right, and the other on the left, in the the body of the Spirula, and especially of ihat which forms cavity of the mantle. This visceral mass, which is more or the entire envelope containing the shell, will not permit less rounded and convex in front, and, in general, bifurcated him to admit here the theory proposed by Dr. Buckland, in behind, is entirely enveloped in a very distinct but delicate his “Bridgewater Treatise ;' but if it be not applicable 10 and transparent periloneum, prolonging itself with the the Spirula, continues M. de Blainville, may it not be iporgans of generation, or in the bifurcation of the case, re- plicable to the Nautilus, whose organization' in fact offers sulting from the position of the shell. On dividing the considerable differences, not only in the cephalic appeninantle in the median line, as the figure which M. de Blain- dages, but also in the respiratory funnel divided throughout ville will publish in his Malacozaires indicates, there ap- its length like the branchial tube of the Siphobranchiata, pear

and especially in the shell, which is completely external, and 1st. In front the very considerable funnel entirely closed, in the first chamber of which the animal is lodged, and can and advancing probably also under the cephalobrachial retire therein completely? This, says M. de Blainville, is mass, to judge of it at least from the eye, left nearly in situ. what I cannot decide. At all events, it is sufficiently diffi

2nd. The branchiæ, long, narrow, triangular, directed on cult to conceive that if the lubuliform prolongation which each side with the point forwards, free, and only retained is lodged in the siphon of the shell of the Spirula is not by a very loose membranous bridle, except at iheir base, hollow, it should be so in the Nautilus, and that if the periwhere the vascular peduncle is found.

cardium or the peritoneum does not communicate with this 3rd. Towards the middle of the lower surface of the pretended canal in the Spirula, it does communicate with visceral mass, the intestinal canal terminating in a small, it in the Nautilus; and this so much the more, inasmuch free, tloating appendage, widely open, absolutely as in the as it is at least an unusual thing that this species of divercuttles, and acrompanied throughout its extent between the ticulum of the pericardium should thus continue in all the two masses of the generative apparatus, by the canal of the whorls to the summit: 'aussi, continues M. de Blainville, ink-bag, containing black malter, which M. de Blainville attendrons nous avec quelque impatience que M. R. Owen pressed out by a small orifice situated at the left of the ait pu éclaircir nos douies au sujet du Nautile; jusque là

nous pouvons au moins dire que la théorie de M. Buckland 4th. The principal part of the female organs of gene- n'est pas applicable à la Spirule. Aussi en proposeronsration, viz, on one side (the right) a considerable ovary, and nous une beaucoup plus simple et plus en barmonie avec on the other, doubtless, an organ of digestion, forming both ce que nous pouvons voir tous les jours chez les planorbes together the whole luwer surface of the mass, and prolong- et les lymnées de nos marais.' ing itself more or less backwards on each side of the enve Whether Professor Owen will set to work to clear up these lope of the shell. The mass of eggs came forth a little doubts we know not; but we venture to think that, if he below the fasciculi of the muscular attachment of the does, he will be wasting time that might be much better cephalic mass to the shell. They were few and very large, employed. If M. de Blainville was unwilling to give credit being a millemetre in length by three quarters of á mille- to ihe Professor's positive affirmation that the hollow memmetre in width. Their envelope was hard and friable; it branous tube traverses the siphon of Nautilus, and to the contained an amber-coloured matter, nearly solid, and Professor's figure exhibiting it, he migbt have satisfied which was, M. de Blainville thinks, without doubt the himself of its existence by examining the dried remains of vitellus; but he could not perceive any trace of a fætus, in it in any old recent Nautilus shells, which we never underconsequence of the early stage of development in which stood to be rare at Paris. Tu hollow tube is equally dethey were.

monstrated by the condition of the fossil Nautili. M. de Blainville reminds the reader that he has already In the museum of the Royal College of Surgeons in adverted to the fact, that in all the individuals which he had London there is a preparation (No. 900 B, Physiological observed, the cephalic mass and its appendages liad been Series), made by Professor Owen, and described by him in torn away at their point of junction with the body; but on the second volume of the admirable Catalogue published in one, the least mutilated, the end of the muscular sheath 1834. This preparation exhibits the circulation and respiwhich traverses the @sophagus was preserved. Its anterior ratory organs of the Pearly Nautilus (Nautilus Pompilius); extreinity, which gues to the head and its appendages, was and the description is given in this work. [Nautilus, vol. truncated at the point of abstraction; but the posterior ex- xvi., p. 112.) We have minutely examined the preparation, tremity was in tolerably good preservation; one might see and can vouch for the accuracy of the description: no one that, narrowing as it proceeded, it attached itself to a Mesly at all versed in the subject oan see the former without being lamina, which completed the bottom of the first chamber of satisfied that the prolongation of the mantle and memthe shell, forming a sort of hood or cap continued by means branous tube to form the siphon is tubular, and not solid. of its circumference with the envelope of the shell, and It goes through the pericardium, and consequently commugiving origin, at the bottom and towards the inferior border, nicates by means of the valvular foramina at the base of w a lubiform prolongation penetrating into and attaching the gills with the branchial chamber.* P. C., No. 1404.

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anus.

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