with a nucleus of the form of a vesicle with nearly central nucleolus. The outrunners arise at the two poles of the ellipsoid, which last the author distinguishes as peripheral and central poles.

From the peripheral pole arises an usually forkshaped outrunner, whose free extremities just reach the surface of the epithelium. This outrunner is divisible into two parts, the handle of the fork and the prongs. The longer the former is, the shorter are the latter, and vice versa. The prongs are usually two, less frequently three. All the prongs are extremely slight cylindrical rods. The optical properties of the handle and prongs are those of very fine, pale nerve fibres: they have the homogeneous appearance and the dull lustre found, for example, in the axis-cylinders occurring in the posterior layers of the cornea of the frog. Chemically, too, they almost entirely resemble the latter. They are, moreover, flexible and tolerably elastic.

Outrunners dividing dichotomously arise also from the central pole. These too agree in their physical and chemical properties with minute axis cylinders. They lie in the spaces between the bodies of the cylinder-cells, and their extremities reach the surface of the stratum of connective tissue of the papilla. The latter in this situation exhibits a lamellar thickening, perforated by abundant ramifications of very delicate pale nerve fibres.

The author does not feel in a position to decide whether the central outrunners of different fork-cells pass into one another, or whether each descends separately to the connective tissue stratum of the papilla. In any case these outrunners form with their dichotomous ramifications an extremely dense fibrous network, which almost completely fills the space between the bodies of the cylinder- and of the inferior fork-cells.

While Dr. Engelmann considers the cup- and cylinder-cells to be only epithelial cells of peculiar construction, he looks upon the fork-cells as the extremities of the gustatory nerves, as will appear, he says, more clearly from the description of the nerves yet to be given. As to the epithelium investing the remaining surface of the papilla, it consists of ciliated cells and non-ciliated cylinder epithelial cells. The first of these form a small girdle or garland around the circular layer of the nerve epithelium, a closed ring, as it were, having the breadth of one, or at most of two ciliated cells, and not extending, as stated by earlier observers, over the whole surface of the papilla. The sides of the papilla are covered with ordinary non-ciliated cylinder epithelium.

The nerve fibres of the gustatory papillæ.-The stratum of connective tissue in the papilla consists of a greater under por

tion formed of loose, and a less upper portion, laminated, composed of dense tissue. The former contains the blood-vessels, the terminations of the divided muscular fibres, and the darkly defined nerve-tubes. The upper part of the stroma of the papilla, called by the author nerve-cushion, consists of very dense, nearly homogeneous-looking connective tissue. Inferiorly the nervecushion is rather firmly attached to the other connective tissue of the papilla; upwards and outwards towards the epithelium, it is sharply defined. It has neither connective tissue corpuscles, nor nuclei, nor outrunners of muscular fibres, nor blood-vessels, nor elastic fibres, but a surprisingly large quantity of extremely fine, pale nerve fibres. It forms the basis on which the whole nerve-epithelium rests.

"The five to ten medulla containing nerve fibres of the papilla run in the axis of the latter, undivided, to the under surface of the nerve cushion. On entering this, or shortly before, they become more pointed, and suddenly lose their dark contours; their neurilemma, however, coalesces with the dense tissue of the nerve-cushion. Immediately after their entrance the nerve fibres, which have already become very slight and pale by repeated dichotomous subdivision, form a delicate nervous network, which extends horizontally through the whole inferior half of the nerve-cushion, and whence very numerous extremely fine branches, usually again subdividing, ascend in a tolerably straight direction to the free surface of the nervecushion. The continuations in the epithelium of these branches, which perforate the nerve-cushion, are the above described central out-runners of the fork-cells."-(P. 22.)

This, which appears to be the principal point in the work, we have stated in the author's own words. Previous observers had seen the nerve-cushion, but had taken a different view of it. Key looked upon it as a colossal extension of the neurilemma, and called it "Nervenschale."

Dr. Engelmann does not profess to have absolutely demonstrated the connexion between the nerve-fibres and the forkcells above referred to; but he shows that such a connexion is all but certain, though it appears just to escape positive detection through the insufficiency of our optical instruments. "We see delicate, pale nerve-fibres reach in very many points the surface of the nerve-cushion: we see from this surface equally delicate, extremely numerous fibres, having the same properties as pale nerve-fibres, issuing and continued directly into the substance of the fork-cells. If we now assume the existence of a connexion between the former fibres and these latter, we do only what is necessary: we assume what is by far the most probable."

Certain physiological questions suggest themselves, such as,

whether each fork-cell is connected with only one or with several dark margined nerve-fibres? The latter view the author believes to be the more probable. In addition to the arguments with which he supports this opinion, we might perhaps suggest, that such an arrangement is more in accordance with what we observe in the nervous system generally, as in the multipolar cells of the spinal cord. This and one or two questions Dr. Engelmann leaves, however, for the present undecided, "Content with the result, that the peripheral extremities of the gustatory nerves are organs of peculiar structure: the fork-cells, which are characteristically distinguished from the peripheral terminal apparatus of other nerves, a fresh proof of the truth of the proposition, that specific functions are connected with specific forms" (p. 26.) Dr. Engelmann's valuable paper is illustrated with a well executed plate from drawings by the author himself.

ART. VIII.-The Diseases of the Prostate. Their Pathology and Treatment. By SIR HENRY THOMPSON, &c. &c. Third edition. London, 1868. Pp. 360.

f

Ir would be quite unnecessary to give an extended notice of a new edition of a work so well known as this. The professiona public have already marked in the most decisive manner their appreciation of Sir H. Thompson's clearness, fulness, and trustworthiness as a writer upon the class of diseases of which he treats, and we need, therefore, say no more on that subject. The present edition of this work contains some interesting matters not included in the preceding, the valuable results of increased experience and extensive practice. Amongst these one of the most important is the opinion which a very great familiarity with cases of stone has led our author to form of the value of lithotrity, when the prostate is affected with chronic enlargement. Sir H. Thompson claims for himself a personal experience in cases of this nature only second in extent to that of M. Civiale. He points out, in the first place, the great danger, and often formidable difficulty, of a cutting operation in cases of enlarged prostate, and he discusses seriatim the various obstacles to the successful performance of lithotrity, when this complication exists. Notwithstanding such obstacles Sir H. Thompson shows that Sir B. Brodie speaks in favour of its performance, and relates successful cases; that Civiale was also in favour of it, providing the enlargement was not enormous (in which case he would propose the high or suprapubic operation), and that Dr. Ivanchich of Vienna has recorded statistics of his own experience, which appear to show a much

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more favourable result from lithotrity than has ever been obtained by the cutting operation in such cases, and to this testimony he adds his own experience in these words "I have operated upon numerous cases of calculus of the bladder, in which the prostate was enlarged-certainly in thirty; and I have no hesitation in saying that I cannot consider it as lessening the probabilities of success in skilful hands, or, at all events, to a very small degree" (p. 311). Such an opinion from so experienced an operator is gratifying, since there is no question of the extreme danger of lithotomy in such circumstances. The difficulty of seizing the stone Sir H. Thomson regards with Sir B. Brodie as usually trifling; unless the enlargement is very great and the sinus behind the enlarged gland lodging the stone very narrow, in which case the instrument must be reversed and the stone picked up with it before being crushed, a difficult and dangerous manœuvre. But the common embarrassment is in getting away the fragments. Two recent improvements in the apparatus, however, have made this embarrassment less than formerly. One is the flat-bladed lithotrite, which enables the surgeon to remove a considerable quantity of débris, and is provided with a screw, by which the amount of such débris can be regulated; so that it is less dangerous than the scoop lithotrite formerly in use for this purpose. For details as to this instrument, and the method of employing it, our author refers to a forthcoming new edition of his own work on lithotomy and lithotrity. The second aid in withdrawing fragments is the "exhaustion-syringe" recently introduced into practice by Mr. Clover. Our surgical readers are, of course, all familiar with this instrument, of which Sir II. Thompson speaks in terms of deserved favour. He has used it, he says, nearly 200 times, a convincing proof of its utility. He adds, however, "It is necessary to use all such apparatus with extreme gentleness, and I should prefer to do without it, if possible, as its employment is quite as irritating as a sitting with the lithotrite. Repeated injections, which alter rapidly and considerably the size of the bladder, are always irritating to that organ." Finally, Sir H. Thompson believes that in some cases, assistance may be obtained from the injection of chemical solvents into the bladder, the composition of the stone being previously

ascertained.

We have selected the above out of the numerous interesting topics on which this edition of Sir H. Thompson's work bestows new information, partly in order that our readers may judge of the importance and value of the book, and also on account of the interest of the subject. All those who are old enough to have witnessed much of the practice of lithotomy when it was

the only means of treating stone in the bladder, agree in stating that it was almost uniformly fatal in elderly people with enlarged prostate. Even in our own limited experience we have witnessed most gratifying instances of the removal of stone by lithrotity in such patients, and it is encouraging to hear on such authority as Sir H. Thompson's that such cases are not exceptional. There are few more real advances in modern surgery than the application of lithotrity as the usual method of treating stone in the adult.

ART. IX.-Germinal Matter and the Contact Theory: an Essay on the Morbid Poisons, their Nature, Sources, Effects, Migrations, and the means of limiting their noxious Agency. By JAMES MORRIS, M.D. London. Second edition. 1867. Pp. 111.

SINCE We last noticed Dr. Morris's little book he has added considerably to its size, and has adduced numerous instances more or less favorable to his views. His argument is that solid particles may be suspended for some time in the air, and be borne along to considerable distances by currents in it; that minute portions of organic matter are constantly thrown off by animals and men; and that these floating particles are received into the body, some passing into the lungs, so as to reach the blood. Accepting Dr. Beale's nomenclature of germinal matter and formed material, as expressing the two opposite conditions of living active matter and dead inactive material, he proceeds to show how in many instances, if not in all, morbid action is to be regarded as the result of the contact of the affected organ on tissue with germinal matter in a similarly unhealthy state. The cases which are favorable to Dr. Morris's theory are, of course, those in which infection is admitted by all to take place through the medium of the air, as in typhus, diphtheria, smallpox, scarlet fever, and measles; but we are less able to understand why no case of syphilis should ever occur through particles of syphilitic germinal matter floating in the air developing in some favorable spot for their growth and development. Considering the frequency of the disease, and the remarkable vitality which its germinal matter possesses, as indicated by the difficulty with which it is eradicated from a system it has once contaminated, we should yet doubt whether Dr. Morris would admit the validity of his own argument, were a patient with a wellmarked chancre to urge that it had arisen from a few floating syphilitic particles which had unfortunately alighted on a pimple. Yet why should this not be so, at least in rare instances, since