STOMACH AND INTESTINE. 



339 





though T have sometimes found below the 

 surface a faint acidity, such as might have been 

 clue to a mere admixture or imbibition of the 

 fluids above. 



But supposing Dr. Beaumont's conclusion 

 true that the gastric juice exsudes chiefly 

 from the papillary ridges that intervene be- 

 tween the tubes what office shall we assign 

 to these latter structures themselves ? 



The occurrence of these tubes is the rule 

 throughout the Vertebrate classes. And not 

 only are the large cells which form their con- 

 tents equally constant, but Goll and Koelli- 

 ker's* researches have shown that it is in these 

 cells, or at least in that part of the stomach 

 which contains them, that the digestive 

 power chiefly, if not essentially, resides. Any 

 indirect or collateral action seems insuffi- 

 cient to explain such a close mutual associa- 

 tion of structure and function : an association 

 which not only ranges a great part of organ- 

 ized nature, but repeats itself in the organ of 

 the individual. Hence, whatever the office of 

 these cells, it is probably concerned with the 

 elaboration of at least one important con- 

 stituent of the gastric juice. It would seem 

 that this constituent is not the acid. Shall 

 we therefore conjecture it to be the organic 

 principle ? 



This conjecture, which rests on foundations 

 so slight that the author feels he has no right 

 to propound it, except in the interrogative 

 form in which it presents itself to his own mind, 

 is perhaps more compatible with the facts 

 at present known than any other that he can 

 indicate. 



It is, however, possible, that the observa- 

 tion of Dr. Beaumont just cited was based 

 on some optical illusion : that, for instance, 

 the lucid specks which he saw on the villi 

 only, had in reality extended up these pro- 

 cesses from dark and depressed openings of 

 the tubes. But even supposing this to have 

 been the case, the superficial acidity of the 

 stomach may be regarded as showing, that the 

 preparation of its secretion is only completed 

 by the cell-growth which lines the lower part 

 of the tubes. 



At any rate, it seems certain that the gas- 

 tric juice is not composed of the dehiscent 

 nucleated cells of the mucous membrane of 

 the stomach. This fact appears so well esta- 

 blished, that we ought not to shrink from re- 

 ceiving it, however it may impugn what is 

 ordinarily understood as the cell-theory. In 

 respect to the latter doctrine, the author can 

 only mention another view, which, though 

 novel and plausible, he has long felt obliged 

 to give up. 



After verifying the obscure cytoblasts which 

 fill the large oval gastric cells, and the more 

 distinct ones which line the axis of the 

 stomach tubef , as well as the gradual trans- 



* Op. dt. Bd. ii. p. 140. 



f It is interesting to notice the close structural 

 analogy offered by these small axial cells to those 

 which line the buccal and duodenal glands. The 

 more so that the latter appear to secrete a fluid which 

 possesses the capacity of effecting a rapid aud impor- 



ition of these into the ordinary columnar 

 epithelia covering the ridges, it occurred to 

 him that this structure, together with Bernard's 

 and Beaumont's observations, were all sus- 

 ceptible of a single explanation. According 

 to such a view, it might be supposed that the 

 mother-cell gradually enlarged, ruptured, and 

 discharged its contained cytoblasts. These 

 arranged themselves in the axis of the tube ; 

 and urged by a gradual pressure, or by the 

 growth of new cytoblasts below them, passed 

 up the follicle to where the mother-cells 

 ceased. There they became attached to the 

 wall of the tube itself, and acquired a colum- 

 nar form by a gradual distention of their 

 interior; a distention, which increased as 

 they approached the summit of the ridge, 

 where they were finally extruded, or burst. 

 Thus the cell which was constructed below, 

 was filled above : a subdivision of the secre- 

 tory process, which might be supposed to de- 

 pend upon the solvent powers of the secre- 

 tion being injurious, either to the production 

 of blastema, or to the multiplication of cells. 

 Such a view seemed more or less to account 

 for the structure of the mother-cell; for the 

 gradual transition of the cytoblast into a 

 columnar cell ; for the superficial acidity, and 

 for the vascular arrangements, of the mucous 

 membrane. It also appeared to be con- 

 firmed by the tendency of the columnar 

 epithelia to cohere strongly with each other, 

 and adhere slightly to the subjacent basement 

 membrane. But the uniform anatomy of the 

 ridges, and the completely structureless cha- 

 racter of the gastric juice, were insurmountable 

 objections, which ultimately led to the com- 

 plete abandonment of this theory. 



And as regards the whole theory of secre- 

 tion by cells, surely it is high time to modify it 

 so that it might involve, not a less immediate 

 action, but a somewhat less extravagant expen- 

 diture, of these minute organs. For the impro- 

 bability which we have shown to be implied in 

 the application of this theory to the stomach, 

 holds good in a far higher, not to say a very 

 different sense, of many other secreting 

 structures. Indeed in some of these, it is 

 obvious, that their situation would involve 

 an enormous waste of life and matter, sup- 

 posing the bulk of their organic products to 

 be really enclosed in deciduous or dehiscent 

 cells. Amongst such we may specify the 

 kidney, the most important duties of which 

 are supposed to be executed by secretion into 

 a cell-growth, from a venous surface 

 a cell-growth of which we may doubt whe- 

 ther it even undergoes a rapid solution, while 

 we can definitely predicate that it is not 

 discharged entire, in any quantity at all com- 

 mensurate with the large amount of solid 

 constituents which is removed from the body 

 in the urine. 



SMALL INTESTINE. The next portion of 

 the alimentary canal is that which is included 

 between the pyloric and ilio-cascal valves, and 

 is named, from its diameter, the small intestine 



tant metamorphosis in another class of organic sub- 

 stances. (Sir p. 302.) 



z 2 



