properties. But we are also favoured with records of experiments on animals and on man made by M. Demarquay, and would wish that this able surgeon had restricted his book-making chiefly to telling us what he had himself observed, and to what conclusions he had arrived. In dismay at the scores of pages of historic matter and of crude hypotheses of past times, the tendency of the reader of his book is to turn over the pages, at the risk of overlooking something important, to discover the résumé or budget of conclusions, which, by a kind dispensation, every Frenchman is fortunately impelled to present his readers. The conclusions respecting the application of carbonic acid and its results in the human economy are found at p. 458; but the necessary shortness of this notice forbids their quotation, and must also be accountable for the remaining brief notice of the contents of this work. In examining the properties of carbonic acid given internally Demarquay has largely quoted our old English writers, Percival and Beddoes; but it is as a topical application that this gas is of the widest utility, and that the author can speak of its value from extensive personal experience with it in surgical maladies. We would direct our readers' attention to the section here referred to on the topical uses of carbonic acid. (Pp. 499–562.) Oxygen is the next gas examined. Its medical history, and the notice of its physiological action, of its mode of preparation and administration medicinally, and of its therapeutical action, extends over upwards of 250 pages, and might, therefore, of itself afford ample scope for a review. M. Demarquay is an original investigator of the properties of oxygen on animal life, and has himself resorted to this gas as a medicine, using it both internally and externally. Its curative value in medical cases, in asthma, consumption, and some other diseases, is attested by himself in a few instances, but he chiefly relies, for the demonstration of the fact to the records of others, particularly to those of Dr. Beddoes, published in 1798. The advantages of oxygen in surgical cases are, however, illustrated and enforced by his own experience as a surgeon. He has used the gas in cases of senile gangrene, in phagedenic and cancerous ulceration, and in instances of broken down health and anæmia attendant on caries. In senile gangrene he envelopes the limb in an indiarubber bag filled with oxygen, and allows the action of the gas to proceed for two or three hours. The most striking results of this proceeding are-the cessation of pain, the excitation of the capillary circulation; the decoloration of the limb which rapidly loses its lividity, and lastly the elimination of sloughs, followed by cure. The third and concluding section of the work is occupied by an investigation of nitrogen, of protoxide of nitrogen, and of hydrogen. The employment of these gases therapeutically has been very limited, and Demarquay can add little to the information presented by older writers and experimenters. A M. Chapelle (of Angoulême) has, we are told, resorted to protoxide of nitrogen as a cure for epilepsy, and detailed his experience in a paper sent to the Academy of Medicine in 1865. The number of cures for epilepsy which have from time to time been vaunted would suggest the inference that epilepsy ought no longer to be met with, or else that each discoverer of a cure has been the victim of delusion. The foregoing observations will suffice to show that the treatise of M. Demarquay is one of great value, especially as a book of reference. ART. VI. An Explanation of the Movements of the Iris, by ROBERT J. LEE, M.B. Cantab., M.R.C.P. London, 1867. Pp. 15. THE object of this little work is to show, as expressed in the author's words, " in a brief and simple manner, that the strong analogy which exists between the movements of the heart and the iris is confirmed by the demonstration of similar nervous structures in the two organs." After certain apposite and interesting allusions to the progress of our knowledge of the anatomy and functions of the nervous system; including reference to the discovery by his honoured father of the great system of ganglia and nerves of the uterus and of the heart, and to the connection existing between the spinal and sympathetic nerves, Dr. Lee proceeds to indicate by examples that ganglionic plexuses of nerves "are intended to unite the cerebro-spinal and sympathetic systems." The best example of this given is in the case of the ophthalmic ganglion, "which bears the same relation to the ciliary muscle and the iris as the cardiac plexus bears to the heart, is similarly connected with the cerebral and sympathetic systems, through the branches it derives from the third and fifth pair of nerves, and from the cavernous plexus." The author then proceeds to refute the opinion held by many physiologists, that such ganglia are sources of the nervous power of the organs which they supply with nerves; and are related to the respective organs in the same manner as the brain and spinal cord are related to the voluntary muscles; and he shows in detail how the nerves from the spinal cord differ from those in various organs, such as the heart. After alluding to the difficulty in explaining the movements of the iris, he draws a parallel between the actions of the heart and iris, and points out how "both act to a great degree independently of the brain, and both display power of movement for some period after death. They both derive their nerves from a ganglion or plexus situated closely and externally to them, and they both possess in themselves, when removed from the body and from connection with the external ganglion, the same property they displayed before." He then remarks that, as a result of the view taken of the nervous system of such organs as display in voluntary movements, it was reasonable to expect "that ganglia would be found to exist in the structure of the iris similar to those in the heart and other organs." Dr. Lee then describes the dissections of the ciliary muscles, and iris, and nerves of the eyes of various animals which he has made, and by which, in spite of the difficulty experienced in following the nerves into the ciliary muscle (especially in animals where it is small, dense, and firm), he establishes the fact that the ciliary muscle and iris possess a system of ganglia and nerves similar to those in the heart, and never before demonstrated; and he exemplifies the subject by describing what he found chiefly in dissecting the eye of the bird representations of the dissected ciliary nerves being well shown by photographic illustrations. He concludes that generally the muscular activity of the iris varies directly with the number and size of the ganglia and nerves connected with it. : Dr. Lee's remarks constitute an important addition to our knowledge of the structure of the eye, and form a very interesting résumé of observations evidently carried on with much industry and carefulness; and in a spirit which we look for in a son of the discoverer of the ganglia of the heart and uterus. ART. VII.-Over de Uiteinden der Smaakzenuwen in de Tong van den Kikvorsch. Door TH. W. ENGELMANN, Assistent bij het Physiologisch Laboratorium te Utrecht. Met Plaat. Nederlandsch Archief voor Genees- en Natuurkunde,' Deel III, 3e Aflevering, 1868. On the Terminations of the Gustatory Nerves in the Tongue of the Frog. By TH. W. ENGELMANN, Assistant in the Physiological Laboratory at Utrecht. Reprinted from the 'Nederlandsch Archief,' Vol. III, Part III, 1868. Pp. 26. IN the investigations detailed in the above paper, the author has had the aid and cooperation of one whose name we are rejoiced to see once more in connexion with physiological re search. We trust that the young Heer Schroeder van der Kolk, Med. Cand., is about to walk in the footsteps of his illustrious father, and to maintain the prestige conferred by the labours of the latter upon the name which his son now bears. Billroth had found that only the fungiform papillæ of the tongue are provided with nerves. At the same time he confirmed the fact, already observed by Leydig, that the terminal surface of these papillæ is covered with a peculiar epithelium. From the previous researches of Schultze on the extremities of the olfactory nerves in the mucous membrane of the nose, he thought a connexion between the nerves and the epithelial cells of the terminal surface of the lingual papillæ not improbable, though he could neither trace the nerves into the epithelium, nor find the analogues of the olfactory cells of Schultze. Fixsen, too, could trace the nerves only into the connective tissue of the papilla. Hoyer3 denies the existence of a connexion between the epithelial cells and the nerves— "E. A. Key made an important step in advance. He discovered not only in the epithelium of the papilla peculiar cells, by him called gustatory cells, but he saw also the dark margined nerves continued into delicate varicose fibres, which ascended into the epithelium. Each gustatory cell possesses, according to him, at its central extremity, a thin varicose outrunner, which passes into a fine nerve fibre." Of Key's researches we gave an abstract in our 29th volume, April, 1862, p. 422. Our notice was, however, taken, not from the German paper above referred to, but from an amplification of the same subsequently published in the form of an academic thesis, by the author, in his native language, the Swedish. Key's important results, obtained under the guidance of Professor Max Schultze, were subsequently disputed by R. Hartmann, who, unable to find the gustatory cells and the fine nerve fibres of Key, considered them to have been artificially produced. Dr. Engelmann is not aware that any recent investigations have been made respecting the terminations of the gustatory cells in the frog. The author's own researches relate to adult specimens of the Rana temporaria. We shall endeavour, as briefly as possible, to lay his principal results before our readers. 1 Müller's Archiv,' 1858, p. 159. 2 Carol. Fixsen, 'De linguæ raninæ texturâ,' Dorpat, 1857. 3 Hoyer, in 'Arch. f. Anat. u. Physiol.,' 1859, p. 481. 4 Key, in 'Arch. f. Anat. u. Physiol.,' 1861, p. 329. * Hartmann, in' Arch. f. Anat. u. Physiol.,' 1863, p. 634 The epithelium covering the circular terminal surface of the papilla consists of three kinds of cells, which he calls cup-cells, cylinder-cells, and fork-cells. All these three varieties are characteristic of the terminal surface of the papilla; they are met with in no other part of the surface of the tongue. They are well defined, having no transition forms among themselves. So long as the cells remain in connexion on the papilla we can, viewing the latter in profile, at most see only two kinds, of which the cup-cells, constituting by far the greatest mass of the epithelium, are the most striking. The author found that he could with glass rods very perfectly isolate the cells in tongues which had lain one or more days in a mixture of equal parts of strong glycerine, and of a four per cent. solution of bichromate of potash. The cup-cells, the "modified epithelial cells" of Key, which are found to the number of several hundreds on the larger papillæ, form the outermost layer of the epithelium investing the terminal surface of the papilla. They consist of cylindrical bodies standing perpendicular to the surface of the papilla, and containing in their lower third a globular, vesicular nucleus, of about 008mm., in which is a central nucleolus of 001mm. in diameter. There is no doubt that the cup-cells are not the extremities of the nerves, but only peculiar, indeed essential characteristic epithelial cells of the gustatory papilla. The cylinder-cells consist of an ellipsoidal body, situated in the deepest layer of the epithelium, and continued in a straight cylindrical outrunner reaching to the external surface of the epithelium. The body is almost completely filled with an ellipsoidal vesicle, the nucleus, in the centre of which lies a small nucleolus. Only a very slight layer of protoplasm surrounds the nucleus. On a review of his observations, the author comes to the conclusion, that neither are the cylinder-cells to be looked upon as extremities of nerves, but as a peculiar kind of epithelial cells, differing in their properties remarkably from other epithelial cells; they are, no doubt, for the most part, the rodcells of Key. The drawings given by the latter make it probable that he had seen them and taken them for the terminal organs of the nerves. He confounded them, however, with the forkcells, of which he seems to have observed only injured specimens. Fork-cells. These remarkable apparatuses, scarcely deserving the name of cells, are, notwithstanding many individual differences, formed after one and the same type. They all consist of a body provided with fibrinous outrunners. The body has the figure of an extended ellipsoid, and is almost completely filled |