THE ALIMENTARY CANAL. 
83 
lower animals, the intestines lie more or less loose in the 
abdomen; but in the Crocodile, and likewise in Birds and 
Mammals, they are supported by a membrane called mes¬ 
entery. 
Fig. 48. —Anatomy of the Carp: br, branchiae, or gill-openings; c, heart; /, liver; vn, 
vn', swimming-bladder; ci f ,intestinal canal; o, ovarium; u , ureter; a, anus; o', 
genital opening; u', opening of ureter. The side-view shows the disposition of 
the muscles in vertical flakes. 
