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Hôtel-de-Ville, at Ypres, has a spire clustered with four exceedingly tall pinnacles or lesser spires. Where there are windows placed against a spire, rising upright like a roof, the term Lucarned the dormers or lucarnes on would express that character; we have therefore not scrupled to make use of it in the annexed table of spires, where it is applied, among others, to those of Lichfield cathedral, which have several tiers of such windows, and are described accordingly. Crocketted and Banded are terms requiring no explanation; but in regard to the first it may be remarked, that spires, otherwise quite plain, are sometimes ornamented with crockets along their edges; and with respect to bands, they are sometimes little more than string-mouldings, but in other cases broad and enriched surfaces. Many of the spires in Normandy are ornamented with such a number of bands, that they form alternating courses with the plain spaces between them. Finialed is a term which does not apply to any of our English spires; but that of St. Stephen's, Vienna, and some other continental spires, have an exceed ingly large and rich finial, which ornament gives them a particular boldness of expression. The Tabernacle spire also is one of which there is no example in this country, but of which the one just mentioned, and those of Strassburg, Ulm (as designed), Thann in Alsace, and many others, are specimens, the tower and spire being carried up from the ground in a succession of diminishing stages, all profusely adorned with pannelling, niches, canopies, pinnacles, and other tabernacle-work, in such a manner that it is barely possible to distinguish where the upright portion or tower terminates, and the spire itself begins, the latter seeming little more than the uppermost stage in continuation of the Neither have we any instances of Open-work spires, or of such as, if not actually perforated, are yet entirely covered with tracery. That at Freyburg, and those at Burgos and Batalha, are all exceedingly rich specimens of the kind. The chapter-house of Burgos also has a series sluite 11

rest.

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of very large pinnacles or small spires of tabernacle charac.
ter. Cambrai and Esslingen on the Neckar afford other
examples of ope:s-work spires.

There are various other circumstances which, though
they do not affect the spire itself, produce greater or less
Very much, for instance,
difference in regard to the character of the structure of
which it is a component feature.
depends upon its situation in the general plan: at Salisbury,
Norwich, and Chichester, the spire is raised upon a tower
at the intersection of the cross, or in the centre of the plan;
whereas in most continental cathedrals and large churches
there are two spires on the towers of the west front, though
in some instances (Strassburg, Antwerp) only one has been
erected. Several however have a single tower and spire in
the centre of the west front (Ulm, Freyburg, Thann in
Alsace), in which case the tower itself begins to diminish
almost from the ground, and the whole becomes what we
have described as of the tabernacle character. In most of
our English churches (not cathedrals) the spire is placed
upon a tower at the west end, as at Grantham, Louth,
Bloxham, &c. If we except Peterborough, where they are
very diminutive, the only English cathedral which has two
western spires is Lichfield, which is further remarkable as
having a central tower and spire also. Besides the richness
and variety thus produced, the larger central spire serves to
balance the whole composition, whereas else the body of the
structure is apt to look low in comparison with the west end.
At St. Stephen's, Vienna, the tower and spire are singularly
placed on the south side of the edifice, it having been in-
tended to balance them by a corresponding tower on the
north side. At Gelnhausen, on the contrary, there is a group
of spires, as already noticed, at the east end.

Although the building itself is by no means a tasteful
example, the façade being in a rude and plain Norman
design, the annexed view of St. Stephen's at Caen will
assist in explaining some of the preceding observations.

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These We have here two western towers and spires, which last | nominated cluster-based, the turrets with their smaller sre not parapeted, but merely embased with turrets and pinnacles at their angles, rising up to a considerable height; consequently they answer to what we have de

stump-spires being clustered around the larger one.
spires are also lucarned below and banded; although in the
cut those circumstances are rather indicated than expressed.

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One circumstance plainly observable is that the whole façade is of narrow proportions, and the space between the towers very small. The spires themselves are short, both in proportion to their own diameters and to the height of the towers, which are carried up so high as to appear very lofty as compared with the rest of the structure. Though so much depends upon circumstances of this kind, almost the only thing that is specified in the usual description of spires is the entire altitude from the ground, which single measurement, unaccompanied by others, gives no idea of the relative dimensions of the spire or how it is proportioned. Some of the loftiest spires, as they are popularly termed, are by no means lofty, being not above a third of the entire height, and not more than four of their own diameters. The spire of Strassburg, for instance, is only 110 feet out of 474, or less than one-third of the tower itself. At Antwerp again the spire is a mere peak crowning the uppermost stage of the tower, while the tower itself is twice as high as the roof of the church. If we compare Salisbury with Norwich, the spire of the latter cathedral will be found, though of less dimensions, much loftier in relation to the

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rest than the other, being in the ratio of 163 to 308 feet, while Salisbury is only 197 to 404. We have therefore drawn up a table of spires, showing the separate as well as united heights of the respective towers and spires; and although in some instances we have been unable to obtain those dimensions, the table supplies other information in regard to the examples mentioned in it, and will at least serve as a model for a more complete list of the kind. In addition to it we will here briefly enumerate some of the examples arranged according to the proportions of the spires, or their heights as measured by the diameters of their bases: Siz diameters in height, or more than five, old St. Paul's; St. Stephen's, Vienna; Norwich; Five, or more than four, Salisbury, Bloxham, Marburg (4); Four, St. Mary's, Oxford (nearly), Glasgow (do.), Ulm (do.), Bayeux (rather more), St. Stephen's, Caen; Freyburg (rather less); SL Peter's, Caen; Three, or more than two, St. Mary's, Stamford; Welford; Strassburg; Batalha: Two, Oxford cathedral; small western spires, St. Stephen's, Vienna One, Worms, Gelnhausen.

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St. Michael's, Coventry St. Mary's, Stamford

Welford, Gloucester

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An example of a spire on a low circular tower. Lucarned at its base with lofty gabled windows. Spire 3 diameters.

Two west towers, only N.W. spire yet erected. (Comp. to Almanac,
1842.)

Two west spires enriched with tracery, and crowned by large finials.
Two west towers, only N.W. spire.

On south side of church. Example of a tabernacle tower and spire.
Tabernacle example. Tower and spire in centre of west front.
Rich open-work spire. Tower and spire in centre of west front.
Two west towers and spires. Base of spire gabled. Spire 44 diameters.
Do.
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A tabernacle example, with rich tracery-work on spire. Spire about one-fourth of entire height.

Two west towers, only N.W. spire.

Two west spires, the N. W. one loftier and more enriched than the other. Two west spires. The north-west spire has 6 broad bands; the other plain. Diameter at base 27 feet.

Lucarned at base and banded.

Base of spire 24 feet. Spire has 9 bands, with small hexafoil, quatre-
foil, and trefoil apertures between them. Crocketted.
Very rich open-work spire. Diameter at base 19 feet.

Two short or stump but very rich open-work spires, at west end.
Date of spires 1442.

Lucarned, banded, lower band richly moulded and quatrefoiled, and
surmounted by fleurons. Diameter at base 27 feet.

A new church, finished 1831. Lassaulx, architect. Spire, a broach,
splayed off at base. Diameter, above splay, 16 feet; height about
8 diameters.
Church erected by Ohlmuller; completed 1839. Spire an open-work
helm or broach.

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 wine, or alcohol; formerly however the word spirit was given

It will be requisite merely to name a few of those compounds to show how extensively it was used and misapplied to sub

stances of very different origin and composition:
ion: thus nitric
acid was called spirit of nitre; hydrochloric acid, spirit of
salt; sulphuric acid, spirit of sulphur; chloride of tin, spirit
of Libavius; solution of ammonia, spirit of sal-ammoniac,
and so forth.

SPIRIT-LEVEL, a tube of glass nearly filled with spirit of wine or distilled water, and hermetically sealed at both ends, so that when held with its axis in a horizontal position, the air which occupies the part not filled with the spirit or water places itself contiguously to the upper surface. The tube being supposed to be perfectly cylindrical, the exact horizontality of its axis is ascertained by the extremities of the air-bubb.e ceing at equal distances from the middle point in the length of the glass.

and the following is the usual manner of performing the adjustments, preparatory to the instrument being employed on the ground:-

The telescope should, by a proper opening of the legs of the stand, be at first rendered as nearly level as can be estimated by the eye; then, being turned so as to lie vertically above the line joining two opposite screws in what are called the parallel plates (K and L), the spirit-tube is brought to a horizontal position by relaxing the screw nearest to its higher end, and tightening that which is opposite to it: the like operation is to be performed with the other pair of screws, after placing the telescope vertically above them. In order to render the spirit-tube parallel to the axis of the telescope, after the bubble of air has been made to occupy the middle place by the process just mentioned, let the telescope be reversed in the arms (the Ys, as they are called); then, if the bubble does not still occupy the middle, it must be made to do so by successive trials, endeavouring to correct half the error by means of the screw b, and the other half by the screw G.

The spirit-tube is used in determining the relative heights of ground at two or more stations, and in order to render it available for this purpose, it is placed within a brass case having a long opening on the side which is to be uppermost, and is attached to a telescope; the telescope and tube are then fitted to a frame, or cradle, of brass, which is supported on three legs. 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 joins the centres of all the lenses.

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the pinion, M, till the station-staff, placed at any convenient 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 telescope; 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 screws turned till half the displacement is corrected; the like observation and correction may then be made for the other wire: a few repetitions of each adjustment will probably be necessary before the error is wholly removed.

The level constructed by the late Mr. Troughton differs from that which has been above described in having the spirit-tube sunk partly in the telescope; and the latter, being incapable of a movement about its axis, does not admit of a separate adjustment for the intersection of the wires.

The case containing the spirit-tube is made to turn on a Joint at one extremity, as a, by the revolutions of a screw, b, at the opposite extremity; and the telescope rests, near each end, within two arms at the top of a small pillar, A or B, the pillar and its arms resembling the letter Y, and the interior sides of the arms being tangents to the tube of the telescope. One of these pillars is made capable of a small movement in a vertical direction by turning a screw, C, at its base, for the purpose of elevating or depressing one end of the telescope and spirit-tube; and in the more perfectly 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 mechanism of these instruEF, the under side of which 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 pillars. A hollow conical socket, H, of brass is screwed to the under side of the plate, and is intended to receive a piece of bell-metal of a corresponding form, which constitutes the upper part of the stand. This piece serves as a vertical axis, upon which the telescope, the spirit-level, and the compass are to turn round horizontally: sometimes however the conical pivot projects from the under part of the plate, EF, and the socket is on the stand.

The three legs which are to support the instrument are firmly fixed to a circular plate, K, perforated at its centre, and having about the perforation a hollow spherical zone, resembling a small inverted cup. In the simpler kinds of spirit-levels a circular plate, L, of the same dimensions as the last, carries above it the pivot before mentioned; and from below it projects a stem, terminating in a ball, which fits the inverted cup or socket. By means of four screws which pass through one of these two plates (the upper plate in the cut), nearly at the extremities of two diameters at right angles to one another, the upper plate is made parallel to the horizon, and consequently the conical pivot which it carries is brought to a vertical position.

The above is a general description, which will serve nearly for every spirit-level at present in use, whatever ba its form;

Let three pickets be driven into the ground in a line and at equal distances from one another, and let the spirit-level be set up successively in the middle between the first and second, and between the second and third pickets; then, having by the screws of the instrument adjusted the spirittube so that the bulbic of air may retain the same place while the telescope is turned round on the vertical axis, direct the object-end of the telescope successively to the station-staves held up on the different pickets, read the several heights, and take the differences between those on the first and second, and on the second and third staff. Now the staves being at equal distances from the instrument, it is obvious that any error which may have existed in the line of collimation, or from the spirit-tube not being parallel to that line, will be destroyed, and the differences between the readings on the staves are the differences in the levels of the heads of the pickets; but unless the adjustments are perfect, this will not be the case if the instrument be set up at any point which is unequally distant from all the pickets; therefore from such point direct the telescope to the staves, and take the differences of the readings as before. On comparing these differences with the former, a want of agreement will prove that the intersection of the wires is not in the optical axis; and the error

may be corrected by means of the screws belonging to the wire plate. After the agreement has been obtained, should the bubble of air not stand in the middle of the tube, it may be brought to that position by the screw b, at one extremity of the case, and the instrument is then completely adjusted. (Simms, Treatise on Mathematical Instruments.)

The spirit-level is usually provided with a clamp, N, and a screw, P, by which, when the axis of the telescope has by hand been brought near the object, the coincidence may be accurately made by a slow and steady motion about the vertical axis.

The spirit-tube or level which is employed for the adjustment of transit telescopes or astronomical circles is contained in a case with feet or with loops at its extremities, in order that it may either rest above or be suspended below the horizontal axis of the instrument to be levelled; also the upper part of the case is furnished with a graduated scale, the divisions of which are numbered on each side of a zero point, this point being usually placed near each of the two extremities of the air-bubble when the tube is in a horizontal position. Having set up or suspended the spirit-tube, the two particular graduations at which the extremities of the air bubble rest are marked; and half the sum, or half the difference of these numbers, according as the extremities of the bubble are in the same or in opposite directions from the two zero-points, being taken, gives the distance of the centre of the bubble from the middle between those points. The level being then reversed, the graduations at which the air-bubble rests are again marked, and half the sum or half the difference is taken as before. A mean of the two distances thus found is the true distance of the centre of the bubble from the middle point on the scale; and the screw which elevates or depresses one end of the axis of the telescope being then turned, till either extremity of the bubble has moved, in a direction contrary to that in which the centre of the bubble had moved from the middle of the scale, through a number of divisions equal to that mean distance, that axis will be brought to a horizontal position. This method is used in preference to that of successive trials, in order to avoid the trouble of making several reversions of the whole instrument.

The levelling-staff till lately in general use for finding the relative heights of ground is a rod consisting of two parts, each six feet long, which, by being made to slide on one another, will indicate differences of level nearly as great as twelve feet. The face of the rod is divided into feet, inches, and tenths, or into feet with centesimal subdivisions; and a vane, or cross-piece of wood, perforated through the middle, is moved up or down upon the rod by an assistant till a chamfered edge at the perforation is seen by the observer at the spirit-level to coincide with the horizontal wire in the telescope. The height from the ground to the chamfered edge of the vane must be read by the assistant; and it being out of the power of the observer to detect any mistake in the reading, it becomes very desirable that the graduations on the rod should be sufficiently distinct to allow the heights to be read at the spirit-level itself. The rod proposed by Mr. Gravat for this purpose is divided into hundredths of a foot by stripes which are alternately black and white, and are numbered at every foot in the usual way with figures great enough to be seen on looking through the telescope; the tenths of a foot are indicated by lines longer than the others. A similar staff has been proposed by Mr. Sopwith and Mr. W. P. Barlow; and the former gentleman, besides the number of every foot, has given a number to every first, third, fifth, and ninth decimal. Mr. Barlow's rod is also divided into centesimals of a foot; but the marks, instead of being stripes whose edges are parallel to one another, have the form of triangles: each tenth mark however is in the form of a lozenge, or double triangle, for the sake of greater distinctness.

SPIRIT-TRADE. [WINE AND SPIRIT TRADE.] SPIRIT of WINE. [ALCOHOL.] SPIROGLYPHUS, a genus framed for a species of Serpula of authors, which makes a groove for itself upon and in the surface of shells. [TUBICOLIDE.]

SPIROLI'NA. [FORAMINIFERA.] SPIROLOCULI'NA. [FORAMINIFERA.] SPIRO'RBIS, Lamarck's name for a genus of Serpula of authors; the white little shell is coiled round into a spiral disc-like form. Common on the shell of lobsters. [TUBICOLIDE.]

SPIRULA. [SPIRULIDE.]

SPIRU'LIDÆ, Professor Owen's name for a family of polythalamous, decapodous, dibranchiate CEPHALOPODA, thus characterized by him:

Animal corresponding in external form to the Decapadous type; internal organization unknown, presumed to be Dibranchiate. Shell partly internal; cylindrical, multilɔcular, discoïd; the whorls separated; septa transverse, con cave next the outlet, and with regular intervals. Siphon marginal and internal, uninterrupted. Genus SPIRULA, Lam.

The character of the family is also that of the single genus of which it is at present composed. Example, Spirulu Australis, Lam.

M. de Blainville, who, in the first volume of the Nouvelles Annales du Museum (1835), had given a detailed account of the anatomy of the shells of Nautilus Pompilius and Spirula, with coloured figures, has since published in the Annales Françaises et Etrangères d'Anatomie et de Physiologie appliquées à la Médicine et à l'Histoire Nature le, his observations Sur l'Animal de la Spirule, et sur l'usage du Siphon des Coquilles polythalames. His account is founded on dead specimens, more or less complete, the remains, doubtless, of the voracity of fishes,' which he owed to the perseverance of MM. Leclancher and Robert, who collected them as they floated dead on the surface of the Atlantic, near the western coast of Africa.

In the last-named memoir, M. de Blainville refers to the former one as having placed beyond doubt, as it seems to him, the very complex composition of the siphon of the shell, 'que,' says he, j'ai montré être formé d'une suite de petits entonnoirs s'emboitant plus ou moins les uns dans les autres, de manière quelquefois à former un tout solide, mais aussi quelquefois ne se touchant pas, et alors les intervalles étant remplis par une partie membraneuse encroutée d'une couche calcaire, de telle sorte que, même dans ce dernier cas, la partie charnue provenant de l'animal ne peut jamais être à nu dans les loges qu'elle traverse.' He adds, that he had concluded from this anatomical disposition that this peculiarity of appearance in the siphon was nothing else than a mode of attachment of the animal to its shell, a sort of muscular insertion by a tubular prolongation, not continuing itself probably throughout the length of the siphon of the shell. Voyons,' he continues, si mes conjectures étaient fondées en étudiant aujourdhui ce que je possède de l'animal dont elle fait partie, c'est-à-dire, je le répète, le trone dont la tête et les bras ont été arrachés.'

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M. de Blainville describes the animal of the Spirula, limited by the mantle, as in the form of a long case, very regularly symmetrical, of an oval shape, slightly compressed at the sides, narrower and more circular forwards, and more elevated and more compressed backwards. The anterior extremity presents a sufficiently regularly trilobated aperture, there being one median lobe a little longer above, and two lower lateral lobes a little more pointed and separated by a median fissure below. This orifice is constituted by the borders of the mantle or of the sac of the Sepiaceans, the collar of the Siphotobranchians forming here a considerable case, in which the head and its appendages can enter and be completely sheltered, a little like the slugs (limaces) under their buckler. The trilobated form of this aperture recals, observes M. de Blainville, sufficiently well that which is at present known respecting that of many ammonites. The posterior extremity of the sac or mantle convex (renflée) and widened vertically (a disposition which is principally due to the shell solidly and vertically encased in the skin) presents, entirely, behind a sort of oblique flatness (aplatissement), at the middle of which is a terminal button, accompanied on the right and left by a small semicircular fin, attached by the right border, and very like that which exists in Sepiola. This mantle or case, in its anterior moiety at least, has, besides, an anatomical structure, which brings to remembrance what exists in the Cala maries, that is to say, it is formed of a contractile very thick lamina or derm constituting the principal part, offer ing on its surface a great number of lacunæ, forming a net; of a nacreous layer on which is the part coloured by small spots, violaceous, doubtless, during life, as in the Sepiola; and, lastly, of a sort of epidermic varnish or glazing, only the contractile part is perhaps still more solid, and capable of more resistance than it is in the calamaries. But in lieu of being sustained in the back by a cartilaginous or calcareous nearly straight lamina, it contains a shell, whose very much elongated and very regular spiral con

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presenting its base open in front, is rolled up vertically backwards behind and below, in coils which are concentric, but disjoined, or not contiguous. This shell is no more really external in any of its points than the cartilage of the calamaries, or the bone of the cuttles. Only fastened on the back and belly in the circumference of a small elongated oval space by the dermomuscular layer, and, as it were, set in it, it forms a sort of hernia, and is not covered in these two places, except by the superficial parts of the skin, the nacreous and coloured layers. With regard to the rest of the spire, it is contained in a subdermic space, Occupying the posterior part of the visceral mass, which is perfectly independent of it, being separated from it by a subcutaneous membrane, which is very delicate, but as distinct as in the sepiaceans. This space or lacuna is, nevertheless, traversed by a bridle equally dermic, which passes from one wall to the other, across the disjunction of the whorls.

itself to the siphon of the first chamber, and then continuing itself without any adhesion, as M. de Blainville supposes, up to its origin towards the summit of the shell; from which he was able in fact to withdraw it without breaking it for a considerable length; so that it may be said that this is in a prolongation of the columellar or retractor muscle of the head and its appendages, and that the membranous siphon itself is only a part of this muscle.

The mantle, the envelope of the shell, and the mass of the viscera, afforded the following analysis:

The shell, entirely free in the dermoid envelope which contains it, has not its terminal excavation augmented in depth by a rather considerable membranous border, as M. de Blainville had supposed in his anatomy of the shell; it is only lined by the membranous hood already described, at the circumference of which terminates anteriorly the fascia of the columellar muscle, and, behind, the subdermic mem brane which forms the chamber of the shell. Placed in the back of the animal, this first chamber contains no viscus either in whole or in part; and very certainly the membranous siphon has no connexion except with the fleshy hood, and none whatever with the peritoneal cavity, at the anterior and lower part of which M. de Blainville states that he could easily recognise the heart receiving the branchial vessels, which are very long on account of the advanced position of the branchiæ.

Before he examines the relations of the shell with the membranous siphon proceeding from the animal, M. de Blainville turns his attention to the mode in which the visceral mass is disposed. Sufficiently considerable, especially at the period when the generative apparatus is in a state of turgescence, it occupies the whole bottom of the cavity of the mantle, prolonging itself more or less on each side of the subdermic envelope, which includes the shell, 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 that 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 to and transparent peritoneum, prolonging itself with the the Spirula, continues M. de Blainville, may it not be p organs 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, and especially in the shell, which is completely external, and in the first chamber of which the animal is lodged, and can retire therein completely? This, says M. de Blainville, is what I cannot decide. At all events, it is sufficiently difficult to conceive that if the tubuliform prolongation which is lodged in the siphon of the shell of the Spirula is not hollow, it should be so in the Nautilus, and that if the pericardium or the peritoneum does not communicate with this pretended canal in the Spirula, it does communicate with it in the Nautilus; and this so much the more, inasmuch as it is at least an unusual thing that this species of diverticulum of the pericardium should thus continue in all the whorls to the summit: 'aussi,' continues M. de Blainville, attendrons nous avec quelque impatience que M. R. Owen ait pu éclaircir nos doutes au sujet du Nautile; jusque là nous pouvons au moins dire que la théorie de M. Buckland n'est pas applicable à la Spirule. Aussi en proposeronsnous une beaucoup plus simple et plus en harmonie avec ce que nous pouvons voir tous les jours chez les planorbes et les lymnées de nos marais.'

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1st. In front the very considerable funnel entirely closed, and advancing probably also under the cephalobrachial mass, to judge of it at least from the eye, left nearly in situ. 2nd. The branchiæ, long, narrow, triangular, directed on each side with the point forwards, free, and only retained by a very loose membranous bridle, except at their base, where the vascular peduncle is found.

3rd. Towards the middle of the lower surface of the visceral mass, the intestinal canal terminating in a small, free, floating appendage, widely open, absolutely as in the cuttles, and accompanied throughout its extent between the two masses of the generative apparatus, by the canal of the ink-bag, containing black matter, which M. de Blainville pressed out by a small orifice situated at the left of the

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4th. The principal part of the female organs of generation, viz. on one side (the right) a considerable ovary, and on the other, doubtless, an organ of digestion, forming both together the whole lower surface of the mass, and prolonging itself more or less backwards on each side of the envelope of the shell. The mass of eggs came forth a little below the fasciculi of the muscular attachment of the cephalic mass to the shell. They were few and very large, being a millemetre in length by three quarters of a millemetre in width. Their envelope was hard and friable; it contained an amber-coloured matter, nearly solid, and which was, M. de Blainville thinks, without doubt the vitellus; but he could not perceive any trace of a fœtus, in consequence of the early stage of development in which they were.

M. de Blainville reminds the reader that he has already adverted to the fact, that in all the individuals which he had observed, the cephalic mass and its appendages had been torn away at their point of junction with the body; but on one, the least mutilated, the end of the muscular sheath which traverses the esophagus was preserved. Its anterior extremity, which goes to the head and its appendages, was truncated at the point of abstraction; but the posterior extremity was in tolerably good preservation; one might see that, narrowing as it proceeded, it attached itself to a fleshy lamina, which completed the bottom of the first chamber of the shell, forming a sort of hood or cap continued by means of its circumference with the envelope of the shell, and giving origin, at the bottom and towards the inferior border, to a tubiform prolongation penetrating into and attaching P. C., No. 1404.

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Whether Professor Owen will set to work to clear up these doubts we know not; but we venture to think that, if he does, he will be wasting time that might be much better employed. If M. de Blainville was unwilling to give credit to the Professor's positive affirmation that the hollow membranous tube traverses the siphon of Nautilus, and to the Professor's figure exhibiting it, he might have satisfied himself of its existence by examining the dried remains of it in any old recent Nautilus shells, which we never understood to be rare at Paris. The hollow tube is equally demonstrated by the condition of the fossil Nautili.

In the museum of the Royal College of Surgeons in London there is a preparation (No. 900 B, Physiological Series), made by Professor Owen, and described by him in the second volume of the admirable Catalogue published in 1834. This preparation exhibits the circulation and respiratory organs of the Pearly Nautilus (Nautilus Pompilius); and the description is given in this work. [NAUTILUS, vol. xvi., p. 112.] We have minutely examined the preparation, and can vouch for the accuracy of the description: no one at all versed in the subject oan see the former without being satisfied that the prolongation of the mantle and membranous tube to form the siphon is tubular, and not solid. It goes through the pericardium, and consequently communicates by means of the valvular foramina at the base of the gills with the branchial chamber.*

VOL. XXII.-3 A

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