298 
SHOVELLER DUCK. 
of shells. Intestine 11 feet 6 inches long ; coeca 64 inches long ; rectum 
3J inches. 
Long intestines, like long bills, often exhibit great differences in the same 
species ; for which reason characters taken from the length of these parts 
must be received with latitude. Even in the Rapacious Birds, in which the 
intestine is generally very short, considerable differences are observed in 
individuals of the same sex and size. It will be seen from the above state- 
ment that the Shoveller has a longer and more slender intestine than any 
other American Duck. In this respect it is analogous to Pandion and 
Haliaetus among the Raptores ; generalizing vaguely from the consideration 
of which, as some have done, one might be apt to conclude that it is more 
piscivorous than the Canvass-back and Pochard, which, however, is by no 
means the case. Although in some birds and mammalia a very elongated 
intestinal canal is connected with piscivorous habits, yet many birds which 
feed exclusively on fish, such as Gannets, Auks, and Guillemots, have the 
intestine of only moderate length or short. It appears simply that when 
for some reason resulting from the economy of the species, the intestine 
must be elongated, it is made proportionally narrow ; whereas if it be expe- 
dient that it should be short, its calibre is increased. 
END OP THE SIXTH VOLUME. 
