414 UTRICULARIA NEGLEOTA. Cuap. XVIL 
change perceptible in the quadrifids or bifids after 21 hrs. 
Four bladders were then treated in the same manner with a 
solution of one part of nitrate of ammonia to 437 of water, and 
re-examined after 21 hrs. In two of these the quadrifids now 
appeared full of very finely granular matter, and their proto- 
plasmic lining or primordial utricle was a little shrunk. In the 
third bladder, the quadrifids included distinctly visible granules, 
and the primordial utricle was a little shrunk after only 8 hrs. 
In the fourth bladder the primordial utricle in most of the 
processes was here and there thickened into little, irregular, 
yellowish specks; and from the gradations which could be 
traced in this and other cases, these specks appear to give rise 
to the larger free granules contained within some of the pro- 
cesses. Other bladders, which, as far as could be judged, had 
never caught any prey, were punctured and left in the same 
solution for 17 hrs.; and their quadrifids now contained very 
fine granular matter. 
A bladder was bisected, examined, and irrigated with a 
solution of one part of carbonate of ammonia to 487 of water. 
After 8 hrs. 30m. the quadrifids contained a good many granules, 
and the primordial utricle was somewhat shrunk; after 23 hrs. 
the quadrifids and bifids contained many spheres of hyaline 
matter, and in one arm twenty-four such spheres of moderate 
size were counted. Two bisected bladders, which had been 
previously left for 21 hrs. in the solution of gum (one part to 
218 of water) without being affected, were irrigated with the 
solution of carbonate of ammonia; and both had their quadrifids 
modified in nearly the same manner as just described,—one 
after only 9 hrs., and the other after 24 hrs. Two bladders 
which appeared never to have caught any prey were punctured 
and placed. in the solution; the quadrifids of one were examined 
after 17 hrs., and found slightly opaque; the quadrifids of the 
other, examined after 45 hrs., had their primordial utricles more 
or less shrunk with thickened yellowish specks, like those due 
to the action of nitrate of ammonia. Several uninjured bladders 
were left in the same solution, as well as in a weaker solution 
of one part to 1750 of water, or 1 gr. to 4 oz.; and after two 
days the quadrifids were more or less opaque, with their con- 
tents finely granular; but whether the solution had entered by 
the orifice, or had been absorbed from the outside, I know not. 
Two bisected bladders were irrigated with a solution of one 
part of urea to 218 of water; but when this solution was em- 
ployed, I forgot that it had been kept for some days in a warm 
room, and had therefore probably generated ammonia; anyhow 
