Cuar. XVII. ABSORPTION BY THE QUADRIFIDS. 415 
the quadrifids were affected after 21 hrs. as if a solution of car- 
bonate of ammonia had been used; for the primordial utricle 
was thickened in specks, which seemed to graduate into separate 
granules. Three bisected bladders were also irrigated with a 
fresh solution of urea of the same strength; their quadrifids 
after 21 hrs. were much less affected than in the former case; 
nevertheless, the primordial utricle in some of the arms was 
a little shrunk, and in others was divided into two almost 
symmetrical sacks. 
Three bisected bladders, after being examined, were irrigated 
with a putrid and very offensive infusion of raw meat. After 
23 hrs. the quadrifids and bifids in all three specimens abounded 
with minute, hyaline, spherical masses; and some of their 
primordial utricles were a little shrunk. Three bisected blad- 
ders were also irrigated with a fresh infusion of raw meat; and 
to my surprise the quadrifids in one of them appeared, after 
23 hrs., finely granular, with their primordial utricles somewhat 
shrunk and marked with thickened yellowish specks; so that 
they had been acted on in the same manner as by the putrid 
infusion or by the salts of ammonia. In the second bladder 
some of the quadrifids were similarly acted on, though to a 
very slight degree; whilst the third bladder was not at all 
affected. 
From these experiments it is clear that the quad- 
rifid and bifid processes have the power of absorbing 
carbonate and nitrate of ammonia, and matter of 
some kind from a putrid infusion of meat. Salts of 
ammonia were selected for trial, as they are known 
to be rapidly generated by the decay of animal 
matter in the presence of air and water, and would 
therefore be generated within the bladders contain- 
ing captured prey. The effect produced on the pro- 
cesses by these salts and by a putrid infusion of raw 
meat differs from that produced by the decay of the 
naturally captured animals only in the aggregated 
masses of protoplasm being in the latter case of larger 
size; but it is probable that the fine granules and 
small hyaline spheres produced by the solutions would 
coalesce into larger masses, with (ime enough allowed. 
