STOMACH AND INTESTINE. 



359 



up into numerous capillaries of about 

 of an inch in diameter. The latter surround 

 the membranous wall of the follicle with an 

 irregular plexus. But where they reach the 

 middle of that part of it which projects into 

 the interior of the intestine, they are curved 

 back upon themselves ; so as to form long 

 loops, that radiate from a central space quite 

 uncovered by vessels. And this appeal ance, 

 which was depicted long ago by Boehm, does 

 but represent, at the surface of the follicle, 

 what the more recent researches of Frei prove 

 to be the vascular arrangement that per- 

 vades the whole of its interior. The injections 

 of this anatomist show, that the capsule is not 

 only surrounded by the network just men- 

 tioned, but is also penetrated by a number of 

 minute capillaries. These, which are of a 

 still smaller diameter than the former ves- 

 sels, leave them at right angles, and reach 

 nearly to the centre of the follicle, before 

 looping back again to its exterior. And 

 finally, some of the uppermost of them have 

 been traced by Koelliker uniting to form the 

 radicle of one or two veins of about T ^oo tn 

 of an inch in diameter; which descend verti- 

 cally through the follicle, without receiving 

 any further branches from the neighbouring 

 capillaries. 



The remaining contents of the follicle form 

 a soft pulpy mass. This is remarkably con- 

 trasted with the contents of the neighbouring 

 lacteals, in the fact that it is always of a pale, 

 semi-transparent, greyish colour ; while the 

 latter are, during digestion, of a brilliant 

 white. The application of reagents under the 

 microscope shows this greyish pulp to be 

 composed of a proteinous substance closely 

 akin to albumen. The addition of water 

 causes it to swell up, and effects its partial 

 solution. And as regards its structure, the 

 mass consists of a moderate quantity of 

 fluid, mingled with a variety of cells. These, 

 however different in their characters, may 

 probably be all reduced to various forms 

 of cell-growth, on the one hand; and various 

 stages of the retrograde solution of blood-cor- 

 puscles, on the other. The latter process, 

 though by no means uncommon, appears 

 always due to an extravasation of a more or 

 less accidental character. It is the cell- 

 growth which constitutes the specific histo- 

 logical character of these albuminous contents 

 of the follicle. 



The cell-growth ranges from distinctly nu- 

 cleated cells, of^J^oth of an inch in diameter, 

 to cells of about one-half, and through these 

 to nuclei of barely one-third, the above size. 

 The latter, however, are of nearly the same 

 bulk as those contained in the largest cells. 

 Hence it would seem that the process of 

 growth which these differences indicate, 

 consists chiefly in the isolation and removal 

 of the cell-watt, from its previously close 

 apposition around the nucleus. In the Sheep, 

 however, Koelliker has sometimes observed 

 an endogenous multiplication of large cells, by 

 a subdivision of their nuclei. And in other 

 specimens from the same animal, he has 



noticed what is very possibly the opposite 

 extreme of the cell-life : the cavity of a 

 large cell filled with large angular corpuscles. 

 These corpuscles are sometimes nucleated; 

 they have albuminous reactions; and they 

 appear to be produced from the ordinary 

 cells of the pulp. They ultimately disappear. 



The function of the agminate follicles it is 

 impossible to specify. Few organs in the 

 body have been the subject of more numerous 

 speculations: speculations, the absurdity of 

 most of which renders them unworthy of 

 any serious mention. And hence, although 

 what we know respecting the structure of 

 these organs justifies (or rather requires) 

 some attempt to indicate their physiological 

 import, the mistakes of others may well teach 

 us how much caution is requisite in making 

 such conjectures. They are, at most, mere 

 guesses at truth. 



The contents of the follicle have just been 

 stated to be composed of a cell-growth that 

 lies in contact with a large vascular surface. 

 Hence it is in the reaction of these innu- 

 merable minute agents on a copious and rich 

 nutritional fluid exsuded from the blood, 

 that we must look for the chief office of the 

 follicle. The fact of various stages of cell-life 

 being present simultaneously, appears to in- 

 dicate, that the cells do not merely select 

 certain materials, but more or less produce 

 them ; by a process which, directly or indi- 

 rectly by absolutely consuming their tissue, 

 or otherwise involves their own decay and 

 death. So far, then, the agminate follicle, which 

 closely resembles the vascular gland in its 

 structure, might be conjectured akin to it in 

 its function ; that function being a choice 

 from the nutritional fluid of certain of its con- 

 stituents, which, after undergoing a metamor- 

 phosis, are subsequently returned into the 

 general current of the blood. 



But such a view omits to recognize some of 

 the circumstances it ought to explain. And it 

 especially neglects one which must be sup- 

 posed of great importance : namely, the situa- 

 tion of the follicle ; or, in other words, its 

 peculiar relation to the cavity of the intestine. 



It is obvious that the position of the agmi- 

 nate follicle with respect to the intestinal canal 

 will admit of a double interpretation. On the 

 one hand, the materials on which its enclosed 

 cells have to act, will probably be derived 

 from the contents of the alimentary canal, as 

 well as from the blood. And on the other 

 hand, they may be ultimately excreted from 

 the body through the intestine, as well as re- 

 turned into that system of closed canals which 

 the blood vessels compose. 



The degree in which the intestine forms the 

 channel of such an ingress and egress, must of 

 course depend upon the directness and effi- 

 ciency of the communication between its ca- 

 vity and that of the follicle. Hence, where 

 the two are in such close contiguity to each 

 other as in the case of the agminate glands 

 of the human subject, we may presume 

 that an efficient transudation of this two- 

 fold nature really does obtain. But where, 



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