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which the form of the sole of the foot undergoes. Instead of presenting its natural concavity, the plantar region becomes convex, both in its antero-posterior and transverse diameters; and hence it is that, in standing or walking, the central third alone, or nearly so, of the outer margin of the foot, is presented to the ground, as has been already mentioned."

"The dorsal region of the foot presents a transverse prominence, situated about an inch below, and in front of the ankle-joint; commencing almost imperceptibly at the external margin of the foot, it gradually becomes more evident till it terminates in a very distinct projection at the inner edge of the tarsus. Between this prominence and the ankle-joint there is a superficial sulcus. The line of the transverse convexity in the plantar region, is opposite to the ridge upon the dorsum of the foot, but its most prominent part is at the outer edge of the tarsus." P. 226.

Such are the principal diagnostic signs of this dislocation. Mr. Smith has twice had an opportunity of ascertaining by post-mortem examination the precise nature of the accident, the luxation having remained unreduced in both instances. The anatomical characters presented in these cases are minutely described, but we must refer our readers to the work, in which they will also find several wood-cuts, without seeing which they would scarcely be able to comprehend Mr. Smith's description of this peculiar displacement of the tarsal bones.

"This remarkable and rare dislocation may be produced by the passage of a heavy body over the dorsum of the foot, but is much more liable to occur when a person, in falling or leaping from a considerable height, alights upon the anterior part of the foot. Under these circumstances, the limb is submitted to the operation of two forces acting in opposite directions; one, the weight of the body and impulse of the fall, tending to depress the tarsal bones, the other, the resistance of the ground, tending to displace the metatarsus upwards: the articulating surfaces thus glide past each other, and the anterior part of the foot is then drawn backwards, and the aspects of its surfaces altered by muscular action." P. 233.

In Chapter VII., on Congenital Luxations of the Wrist-joint, Mr. Smith quotes a case, recorded by Cruveilhier, as an example of luxation of the carpus forwards, but which so closely corresponds with the appearances in a case dissected by our author and regarded as a congenital luxation, that he is compelled to arrive at the conclusion that the French pathologist is in error, and that the lesion in his case is also an original malformation.

Chapter VIII., which treats of Congenital Dislocation of the shoulder, is an extension of a memoir published by Mr. Smith, in the 15th Volume of the Dublin Medical Journal.

Mr. Smith has ascertained the existence of two varieties of this malformation. "In one of these, the head of the humerus is placed beneath the coracoid process; while in the other and more rare variety, it is lodged in an abnormal socket, formed upon the dorsum of the scapula, below the outer and posterior part of the acromion. They may be termed the subcoracoid and sub-acromial congenital luxations, and may exist either upon one side only, or upon both.' Of the latter species our author has seen only one example, but several instances of the former have come under his

observation within the last few years. Five cases are detailed, and representations given of certain alterations in the form of the head of the humerus and of the glenoid cavity, which were noticed in some of the cases. This is a lesion involved in some obscurity, and it is by no means clear that all the cases were really instances of congenital malformation.

Chapter IX. is on Dislocations of the Lower Jaw. Mr. Smith relates a very curious case of what he terms, we think incorrectly, congenital luxation of the inferior maxilla in a man, æt. 38, an idiot from his infancy, who died of diseased lungs.

"While engaged in examining the head, a singular deformity of the countenance, which is accurately represented in the accompanying figure, attracted my observation. The right and left sides of the face seemed as though they did not belong to the same individual, the left being in every respect larger and more fully developed. Upon this side the prominence of the malar bone and of the arch of the zygoma, the development of the masseter muscle, and the fulness of the parotid space, all in a remarkable manner contrasted with the atrophy of the opposite half of the countenance, which, in the situation of the zygoma, presented a concavity in place of a convexity, and in the parotid space a very distinct depression. The countenance was, moreover, crooked in almost every feature. Upon the right side the angle of the mouth was higher than upon the left, while upon the left the orbit was placed a little higher than upon the right; the superciliary arch was much more projecting, and the eye more prominent. "The right side of the face appeared as it were sunk in, and the extremity of the finger could be placed between the parotideal margin of the jaw and the front of the external auditory canal."

"Upon elevating the integuments, and contrasting the dissected muscles of either side, those of the right were found to be much smaller than their fellows of the left side. The masseter, in particular, was atrophied both in length, breadth, and thickness; the temporal and pterygoid muscles also appeared small when compared with those of the opposite side, but as regarded colour and consistence, the muscular fibre did not deviate from the normal condition." P. 276. "When the mouth was closed, and the teeth maintained in apposition, as exact as the abnormal state of the parts admitted of, the external lateral ligament of the lower jaw, instead of being directed backwards, was seen descending obliquely forwards, to be attached to a very imperfectly-developed condyle, which was not in contact with that portion of the temporal bone which, in the natural state, corresponds to the glenoid cavity, being separated from it by an interval of at least a quarter of an inch.

"There was neither an interarticular cartilage nor cartilage of incrustation, the osseous surfaces of the joint being invested by a thick periosteum alone. There was no distinct capsular ligament." P. 277.

"The right side of the inferior maxillary bone was considerably smaller than the left, the atrophy extending forwards to within a very short distance of the symphysis, and affecting the bone as to its length, breadth, and thickness, the ramus being half an inch less in its transverse diameter, and its parotideal margin half an inch shorter than upon the opposite side.

"The lower edge of the bone presented a deep concavity at its posterior part, and the angle was remarkably prominent and curved outwards; the parotideal margin, thin, concave at its upper part, and forming nearly a right angle with the body of the bone, terminated above in a small curved process, directed nearly horizontally inwards, its superior surface being directed slightly outwards, and its inferior slightly inwards.

"This process, which in form somewhat resembled the coracoid process of

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the scapula, was the only vestige of the existence of a condyle, and was destitute of cartilage.

"The external pterygoid muscle was attached to its anterior and inner part, and the external lateral ligament to its outer surface; there was a complete arrest of development in the condyle; the coronoid process was small and thin, and the sigmoid notch could scarcely be said to exist." P. 279.

The temporal malar, superior maxillary and right side of the sphenoid were also more or less atrophied. The right orbit was in consequence smaller than the left. The figure of the base of the skull shows also a diminution in the size of the arch formed by the occipital and parietal bones, though this is not mentioned by Mr. Smith. The case seems to us simply one of arrest of development of all the bones entering into the composition of the right half of the skull and face, the abnormal condition of the articulation of the lower jaw on that side being merely a consequence of the imperfect development of the bones composing it, and proper growth of the left half of the lower jaw. The case, however, is curious and interesting. Mr. Smith next describes the symptoms of the ordinary dislocation of the lower jaw, the detection of which is unattended with difficulty. When the luxation is confined to one side, it is not so easily recognised. The symptom which Mr. Hey found to be the best guide, in this case, is a small hollow which can be felt behind the condyle that is dislocated, which does not subsist on the sound side.

"In

Mr. Smith notices the distortion of the countenance produced by chronic rheumatic arthritis of the temporo-maxillary articulation. the majority of instances, this remarkable disease attacks those of advanced age, and is symmetrical; but occasionally it occurs during the period of adult life. In the latter case, it is generally more rapid in its progress, is accompanied by greater pain, and is more liable to implicate the neck of the condyle and the ramus of the jaw." The nature of the distortion which attends this remarkable affection, varies according as one or both articulations are engaged in the disease.

"When it is confined to that of one side, and has existed for a considerable period, the mouth becomes crooked, the affected side of the jaw being drawn forwards and towards the opposite side, so that the teeth of the lower jaw, upon the sound side, project beyond those of the superior maxilla; but when the disease is symmetrical, the entire of the lower jaw is drawn forwards, and the chin projects just as it does (although from a different cause) in the edentulous subject.

"The glenoid cavity, when the disease has been of long duration, becomes increased as to its circumference, this enlargement being accomplished at the expense of the horizontal and transverse roots of the zygoma, more especially of the latter, which in all cases is to a greater or less extent absorbed.

"It is upon the destruction of this transverse root, or articular eminence, that the distortion of the countenance depends, for when the removal by absorption of this process is, to a certain extent, accomplished, the external pterygoid muscle then draws the jaw forwards and to the opposite side, where but one articulation is diseased, and the muscles of each side act in displacing it directly for wards, when the destruction of the articular eminence is symmetrical." P. 292. We have quoted our author's account of this rheumatic affection of the jaw, as it is one which we have not hitherto recognised, and we believe will be new to most of our readers. In the last Chapter of this work,

Mr. Smith furnishes some additional observations on fractures of the radius, dislocations of the bones of the foot, and congenital luxation of the wristjoint, in support of his views on these subjects.

Our notice of Mr. Smith's work has been so full that our readers will be able to form some estimate of its value. He has endeavoured to throw light on injuries and affections of an obscure, complicated, or rare character, and to assist surgeons in discriminating more clearly than heretofore the various lesions implicating the principal articulations. In the execution of this task he has collected many important and interesting facts, which he has described clearly and discussed without bias, and with a desire to advance our knowledge of surgery. The work is enriched with a large number of wood-cuts, which were really necessary to enable the readers of it to comprehend the descriptions in the text. These figures are well executed, but there is a hardness about most of them, and a want of that finish which may be observed in the best woodcuts which illustrate the works that have recently issued from the London press.

Should this work reach a second edition, we advise Mr. Smith to give his numerous extracts from the French writers in translation, instead of in, or in addition to, the original. He may reply that this is unnecessary, as every well-educated medical man in the present day is able to read the French language; which is true enough; but we know that there are a great many members of our profession who unfortunately are not well educated, or who are unacquainted with any other modern language than their own, but who may nevertheless desire to consult Mr. Smith's book, and it is for their benefit that we make this suggestion.

LECTURES ON THE COMPARATIVE ANATOMY AND PHYSIOLOGY OF THE VERTEBRATE ANIMALS; Delivered at the Royal College of Surgeons of England in 1844 and 1846. By Richard Owen, F.R.S., Hunterian Professor and Conservator of the Museum of the College. Part I.-Fishes. Illustrated by numerous Woodcuts. 8vo. Longman and Co. 1846.

THE second volume of this important work has now made its appearance, and calls for an early notice at our hands. It may be considered as by far the most important of the series, as it enunciates the new and profound views of its distinguished author on some of the highest and most abstruse theories of transcendental anatomy. It is for this reason that we now propose to take up this volume for our separate consideration, not associating it, in our notice, with the former one, nor waiting until the work shall be completed by the publication of the third and concluding part.

The promulgation of theories, and many of them highly ingenious and even exhibiting no small degree of philosophical generalization, in the structure of particular groups of animals, is not a new thing. The first, however, who carried his views of the subject into anything like a full and consistent plan, was Geoffroy St. Hilaire; whose genius, as brilliant as it

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was bold, gave to his theories a character of deep and varied interest, by which the philosophical world was equally astonished and charmed. The fascination which belonged to his splendid and glorious idea (and we feel no hesitation in designating it by so strong a term,) the charm which always attaches to a single, uniform and all-inclusive theory dazzled his first disciples, and prevented them from seeing the inconsistencies and incongruities which in truth were included in it, whilst those to whose clearer vision these faults were apparent, became the founders or the adherents of an opposing party, who rejected the principle on account of its defects, and fell into a greater error in endeavouring to escape from the less.

Passing the clever vagaries of Carus, and the hypotheses of many others of various degrees of demerit, we believe that it was left to Professor Owen, by the enunciation of a clear and tangible theory, by the discrimination between those structural elements which are essential to the relation of beings of the same type, and those which only subserve a definite and, as it were, individual purpose, to exhibit the true conditions of that beautiful and unerring law which provides for the various requirements of every subordinate group or species, by modifications of the typical structure, rather than by the loss of any of its essential elements and the substitution of others foreign to it; whilst it recognises, in certain subordinate structures which have hitherto been confounded with the former essential and typical ones, a certain superadded and non-essential development of abnormal elements. To these two distinct classes the author gives the terms-somewhat pedantic perhaps, but sufficiently expressiveof homological and teleological structures.

Before we advance, however, to the more detailed development of this theory, we will allow the author to exhibit his general views on the structure of the great division of the animal kingdom, the Vertebrata, on a portion of which the present volume treats.

We are met, in limine, by an expression which we confess we do not fully understand; are we to consider it as declaring the deliberate judgment of the author on the comparative merits of the different objects of study and research there mentioned? The passage to which we allude is as follows:

"And first, permit me to dwell a little on the inestimable privilege which we enjoy, in entering upon our professional studies by the portal of anatomy. "How vast and diversified a field of knowledge opens out before us as we gaze from that portal! Consider what it is that forms the subject of our essential introductory study; nothing less than the organic mechanism of the last and highest created product which has been introduced into the planet; contrast this, which both Sage and Poet have called the noblest study of mankind,' with the dry and unattractive preliminary exercises of the Lawyer or the Divine."

Indeed! is this Professor Owen's deliberate opinion? We are oldfashioned enough to think that there may be a still nobler study to which the mind, the heir of immortality, may be devoted. We have fancied, without any derogation from the value and importance of the casket, that the gem contained within it was still more worthy of contemplation—that the value and interest of the body depend mainly on its being the seat of the immortal part of our nature, and that the divine emanation by which the corporeal form is animated and ennobled. may afford subject for a