346 PROCEEDINGS OF THE ACADEMY OF [May, 



toward fixing fluids and staining capacity is due to a differ- 

 ence in purity. The granules, densely packed about the nuclei 

 of the young cells, are in a nascent state, consisting of a pure 

 ferment-forming substance. lu the larger cells — that is, as the 

 young cells mature — the zymogen takes up falty substance from the 

 cytoplasm, and this dilutes the ferment-forming body, at the same 

 time rendering it more soluble in certain reagents and improving its 

 capacity for certain stains. 



a. — Relation of Secretion to Feeding. 



The column of Table I headed " Secretion in lumen " exhibits 

 the relation of the quantity of secretion in the lumen and its pas- 

 sage into the intestine to the stages of absorption of proteids (raw 

 meat) exhibited in the last columns. Owing to the method of 

 removing from the animal tne intestine and hepatopancreas, by 

 which their connection is often broken, the later datum was not in 

 all cases to be had. It will be seen, however, that beginning with 

 fresh condition — that is, animals taken quite at random from the 

 natural habitat— and passing through the starved condition (No. 3) 

 up to 124 hours after feeding, and to an animal kept a whole week 

 on raw meat, there is almost always an ' ' abundance ' ' of the secre- 

 tion in the lumen. In a few cases, as No. 3 (starved) and 42 

 (ninety-eight hours after feeding), the quantity in the proximal end 

 of the tube is small. There is no very marked decline, although it 

 might well be expected in the course of another day or two of fasting. 



The chemical reaction of the secretion, as determined by leasing 

 the ' ' liver ' ' on litmus paper, is slightly alkaline for animals taken 

 from the natural state. The staining affinity of the secretion seems 

 to vary. Thus in 13 and 22, both of Oniscus, starved twenty-one 

 days and killed sixteen and twenty hours respectively after eating 

 in the same fluid and treated precisely alike (stained in Biondi- 

 Heidenhain), in the one case the secretion takes the methyl green, 

 in the other the plasma ssain and comes out red. A number of 

 such intestines have been seen, and both colors have been seen in 

 the same intestine. If the staining is a chemical reaction, and there 

 seems to be no doubt of it in this case, we must conclude that the 

 reaction of the secretion must vary from acid to alkaline (as deter- 

 mined by Biondi-Heidenhain stain as an indicator). Not enough 

 cases have been noted to establish any cycle of such change, or to 

 relate it in any way with the quantity or kind of food. It is inter- 



