298 SHOVELLER DUCK. 



of shells. Intestine 11 feet 6 inches long; coeca 6i inches long; rectum 3\ 

 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. 



Genus V.— FULIGULA. SEA-DUCK. 



Bill about the length of the head or shorter, higher than broad at the base, 

 depressed toward the end, the margins parallel, slightly dilated towards the 

 end, which is rounded, the frontal angles rather pointed; upper mandible 

 with the dorsal line generally declinate, but various at the base, being often 

 prominent, the ridge broad at the base, narrowed at the middle, enlarged and 

 convex at the end, the sides nearly erect at the base, gradually more decli- 

 nate, the edges soft and internally lamellate, the unguis oblong and decurved; 

 lower mandible flattened, being but slightly convex, with the angle very 

 long and rather narrow, the dorsal line very short and straight, the edges 

 internally lamellate, the unguis flat, obovato-elliptical. Nostrils sub-medial, 



