690 INTERNAL SECRETIONS AND PRESERVATION OP LIFE. 



a substance containing albuminate of iron, free leucocytes 

 crowded with granules of iron-pigments, in the intestine. 

 Some of these cells appeared to pass out through the epithelial 

 cells, while others advanced into the subepithelial elements. 

 Macallum had also found them in the venules of the villi, the 

 spleen, etc. 



We have just seen the reference of Kanthack and Hardy 

 to the "considerable increase in the number of lymphocytes 

 in the blood, and, therefore, a fall in the share of the total 

 white corpuscles" caused by a meal. Both these two phenom- 

 ena become normal events instead of a "disturbing factor" if 

 the process of digestion includes the use of a large proportion 

 of adult or fully-developed leucocytes to transport various 

 materials from the intestinal canal to various parts of the or- 

 ganism. It is evident that under these circumstances the im- 

 mediate neoformation of lymphocytes, and their rapid growth, 

 as is probably their wont, to the state of mature cells, becomes 

 a sine qua non of continued existence. 



Overlooking the possibility of such a function, and led by 

 his own hypothesis to ascribe to intracellular processes the 

 presence of food-products in the leucocyte, Metchnikoff writes 21 : 

 "The digestion of proteid substances by the leucocytes is well 

 shown by the gradual changes that take place in the muscular 

 fibers which have been inglobed by leucocytes in cases of acute 

 muscular atrophy. The presence of peptone in leucocytes, which 

 has been so often proved by Hofmeister, is sufficiently ac- 

 counted for by this fact of intracellular digestion, and need 

 not, therefore, be referred, as done by this author, to an ab- 

 sorption by these cells of the peptone formed in the alimentary 

 canal" We need hardly observe, however, that, added to the 

 foregoing testimony, Hofmeister's view seems sustained. 



Indeed, the process to which the peptones owe their pres- 

 ence within the cell is not difficult to trace, if the latter's me- 

 chanical functions, as we have construed them, are taken into 

 account. The presence of peptones within the perinuclear 

 vacuole being an accepted fact (since it is recognized by both 

 investigators), the presence therein of substances from which 



21 Metchnikoff : Loc. cit., p. 124. 



