Baird's report for the year 1863, which is contained in the volume now before us, gives us the gratifying intelligence that the "interest in the subject of Natural History, which received so material a check in 1861, and showed symptoms of revival in 1862, has continued to manifest itself still more strongly during the year 1863." Amongst other explorations, wholly or partially carried on by the Smithsonian Institution, with the main object of working out the Zoology and Botany of the North America continent, Professor Baird speaks of Mr. Kennicott's expedition to Arctic America, which has resulted in the acquisition of a very large quantity of valuable material. "The collection received in 1863, filled forty boxes and packages, and weighed in the aggregate, about 3000 pounds." Another well known Smithsonian collector, Mr. John Xantus, had left for the West Coast of Mexico, and was making extensive collections in that quarter. Large series of natural objects had also been received from Dr. Van Frantzius in Costa Rica, Dr. Sartorius and Professor Sumicrast in Mexico, Captain J. M. Dow in Panama, Mr. W. T. March in Jamaica, and the Hon. C. R. Buckalew in Ecuador-not to mention numerous other collections of more or less importance. These materials are worked out by different Naturalists to whom they are submitted for that purpose, and the results published in the Smithsonian "Contributions to Knowledge," and "Miscellaneous Collections "-to different papers in which we have already on several occasions called our readers' attention. We must all acknowledge that the Smithsonian Institution is worthily carrying out the views of its founder, "to increase and diffuse knowledge among men." Lastly, we have Professor Agassiz's Annual Report on the Museum of Comparative Zoology, at Cambridge, of which we have before spoken in this journal,* and which is a third institution, young as yet, but also, likely, as it progresses, to do good service in the cause of science. Here again we hear of large accessions of specimens from every quarter, and of improvements in internal arrangements likely to conduce to the future welfare of the Museum. "The publications of the Museum" have, it is allowed, "proceeded very slowly," and Professor Agassiz acknowledges some disappointment with certain of his collaborateurs, whose investigations, made under his direction, have been "without his knowledge published * Nat. Hist. Rev. 1863, p. 524. elsewhere." We have not space left to discuss the special reports on Mammals and Birds by Mr. J. A. Allen, on the Reptiles and Fishes by Mr. Alexander Agassiz, who appears to be following worthily in his father's footsteps; on the Insecta, Crustacea, and Annulata by Mr. P. R. Uhler, on the Mollusks by Mr. J. G. Anthony, and on the Brachiopoda by Mr. N. S. Shayler. Suffice it to say, that great activity seems to be manifested by all these gentlemen. And though we believe their eminent leader Professor Agassiz himself is now recruiting his health (and at the same time adding to the riches of his collection) in the wilds of South America, we have no fear that his temporary absence will seriously affect the labours of this energetic corps. Unless we are much mistaken, the Museum of Comparative Zoology of Cambridge, is destined hereafter to play no mean part in the Annals of Science. XLI. THE STRUCTURE OF THE MEDULLA OBLONGATA. THE GREY SUBSTANCE OF THE MEDULLA OBLONGATA AND TRAPEZIUM. By John Dean, M.D. (Smithsonian Contributions to Knowledge.) Washington, 1864. ་ In the Elementa Physiologiae' of the learned Haller, a few paragraphs suffice for the description of the Medulla oblongata. At the present day, an account of the same organ, comprehensive enough to include the recent microscopic researches of Stilling, Schroeder van der Kolk, Lockhart Clarke, Koelliker, and others, would fill at least as many chapters. Nor can the increase be considered as a mere increase of words, or even as a mere increase of pedantic knowledge lacking wisdom. Every page of a faithful description of the minute anatomy of the nervous centres represents a large amount of very hard work, and every page is full of facts which give a promise of being some day rich in meaning. There is hardly any field in Biology in which labour is more praiseworthy or more fruitful. We may gladly welcome, therefore, any fresh careful study like that embodied in the memoir now before us. In it Dr. Dean, of Boston, U.S., well known for his contributions to the minute anatomy of the spinal cord, attempts to give a descriptive account of the grey substance of the medulla oblongata in man and mammalia, and of the organ in mammalia known as the tra pezium. The gradual development of the various parts of the grey matter of the spinal cord as they pass upwards towards the brain is carefully worked out; the rise and fall of the nuclei of the special nerves,-arranged as they are in two series, the hypoglossal abduces, facial and molar part of trigeminus in one line, and the spinal accessory, vagal glossopharyngeal, auditory and sensor part of trigeminus in another, - are fully described; the accessory ganglia, viz. the upper and lower olivary, the restiform, and postpyramidal bodies, &c., are investigated; and the relations of all these parts to each other and to the nerve roots are discussed at length. The author has naturally found that a large part of his work ended in a corroboration of the results arrived at by other observers. Particularly striking is the coincidence of his descriptions and views with those of our own Lockhart Clarke. In several instances he omits a detailed account, because, as he candidly and modestly states; the facts had been previously so well and accurately described by the English anatomist, that his own words would read like a mere quotation. We are not so fertile in original observers as not to feel gratified by such praise as this, coming as it does, too, from the other side of the Atlantic; and may well be proud of a man of whom it may almost be said that he described nothing which he has not seen, and seen nothing that was not visible. In speaking of Dr. Dean's work as being in great measure corroborative rather than new, we do not in any way intend to depreciate it. On the contrary, seeing what a host of discordant and conflicting opinions almost always rise up round every fresh point in biological science, we may perhaps feel inclined to attribute very great importance indeed to faithful and clenching work of corroboration. For the establishment of a scientific verdict there should be at least two witnesses, and the second should share, in large measure, the credit of the first. But, besides corroborative work, there is in this memoir, a great deal of new matter, consisting mainly of elaboration of points previously determined and of correction of erroneous ideas. Labour of this kind can only be properly appreciated by going over the same ground with the scalpel and the microscope; but we may call attention to one or two points which are of especial importance, since they have been made the basis for some physiological reasoning, and have been brought prominently before the English medical public in the translation of the work of the late Schroeder van der Kolk, pub lished by the New Sydenham Society. If Dr. Dean is right, the views of the celebrated Utrecht Professor are wrong; and in that case it were well that they should be recalled or arrested before they have sunk too far into medical practice. Schroeder van der Kolk, as is well known, having satisfied himself that there was little or no direct decussation between the two hypoglossal nuclei, that, on the other hand, the two olivary bodies not only were largely united with each other, but likewise possessed special fascicules (also observed by Lenhossek), connecting each with the hypoglossal nucleus of the same side, and having observed that in the animal series the development of the olivary bodies corresponded with the amount of movement possessed by the tongue, drew up a theory that these structures were intimately concerned in or presided over the processes of deglutition and, more especially, of speech. And he supported this opinion with facts gathered from pathological researches. Dr. Dean, however, states, that there is, at least, some decussation between the two hypoglossal roots, which, therefore, may be presumed to be competent of bilateral action without the intervention of any third body. In the cat he finds this decussation very marked. He denies, moreover, the existence of any peculiar communication between the olivary bodies and the hypoglossal nuclei, and hence rejects Schroeder van der Kolk's theory of the special function of the former. At the same time he admits that some fibres from the hypoglossal nuclei, as well as from all the other nuclei of the medulla, 'pass among the cells of the olivary bodies, and, in many cases, are doubtless continuous with their processes.' And dwelling on the fact that those bodies are also largely connected with the system of arciform fibres,. with the system of longitudinal fibres and with the antero lateral nucleus and caput cornu, he is led to agree with Clarke in attributing to them a co-ordinating influence.' The remarkable nuclei, which were first pointed out by Clarke, and which have received the name of 'upper olivary bodies,' were thought by Schroeder van der Kolk to be especially connected with the facial nerve. And their great development in carnivora and feeble conformation in herbivora led that observer to regard them as organs for the expression of passion by facial movements. Dr. Dean has traced the upward development of these bodies from two nuclei existing on the outside of the lower olivary bodies, which he has especially described and named the ' antero-lateral nuclei,' from their position in the antero-lateral columns. He considers them as being, N.H.R.-1865. 2 M like the lower pair, far more intimately united with the arciform fibres than with any special nucleus, such as that of the facial, and consequently attributes to them too a co-ordinary influence.' Dr. Dean, again, is unwilling to admit the existence of any special connection between the trigeminus (which he always, unwisely as it appears to us, calls the trificial) and auditory nerves, such as Schroeder van der Kolk contended for; although he regards the caput cornu, out of which the sensor root of the trigeminus is developed, as a kind of centre of communications for all the nuclei of the posterior columns, spinal accessory, vagal auditory, &c. So, also, with regard to a distinct connection between the auditory and facial nerves, in which Schroeder van der Kolk saw an explanation of certain reflex movements, such as those of the ear, &c., caused by sounds. Dean, while tracing fibres from the auditory nerve into the facial nucleus, cannot find any direct transition into the cells of the latter, and sees no just ground for Schroeder van der Kolk's theory. In fact, the American anatomist seems to have set his face against most physiological deductions from anatomical data. And there is no doubt that such deductions should always be made with the very greatest caution, especially when one is dealing with the minute anatomy of the nervous centres. In no field of observation are there stronger temptations to make a theory, in none less chance of making the right one. The tables indeed might be turned against Dr. Dean, who shares with most of his fellow-labourers a tendency to see every where the instrument of a 'co-ordinating' power. The 'co-ordinating' theory, however, can never prove very dangerous, for no one can see very clearly what it means. On the contrary, it may often be of great temporary use in pre-occupying the ground against usurpers, until, in due time, the rightful owner comes to claim his own. Our author has a very interesting chapter on the development of the bodies pointed out by Clarke, and named by him the Tractus intermedio-lateralis' and the 'Columnae posteriores vesiculosae.' The spinal accessory and vagus are shown to be connected, as Clarke described, with the extension upwards of both these columns. The relations of the vagus and spinal accessory nuclei to certain longitudinal columns, which are continued above into the roots of the trigeminus and below into longitudinal fasciculi intimately connected with the tractus intermedio-lateralis, are also carefully traced out. By this means the homology of the sensory, or posterior nerves |