PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 179 



fore portion; the carinal angle overhangs the mamihrium considerably; 



the fore border of the keel is sharp 



and rather straight. Most of these 



features will be well seen in fig. 4. 



The hracMum and antihracMum are 



of the same length, proportionally 



much shorter than in the Swans, their 



length being shorter than twice the 



tarsus, and only equal to the distance 



between the shoulder and hip joints. 



The j^cJvis is, as fig. G shows, quite 



typically duck-like. Compared with 



fig. 7, the pelvis of a swan, and with 



fig. 22, in Owens Anat. Vertebr., II, 



p. 32, representing a typical pelvis 



of a duck, the diflerences from the 



former and the identity with the latter 



are easily perceptible, the greatei 



breadth and wedge-shaped form ot 



the post-acetabular sacral roof being 



the most essential characters. 



In nearly all the above-mentioned 

 features Coscoroha differs from the 

 Swans, while the same characters 

 draw it near to the true Ducks ; or, in 

 other words, in nearly all the points 

 wherein the Cygnimc differ from the 

 Anatinw, the Coscoroha agrees with 

 the latter. 



There can, after this, be no doubt fji 

 where it, for the future, should be 

 placed in the system.* 



It is, however, unquestionable that p^i.^^^ cyonu. gim,,.- 

 the Swans, through Coscoroha, are Mus. 



more nearly allied to the Anatinw than they are to the Anserirue. 



No. 158C, Army Med. 



But 



* The genus Coscoroha only comprises two species, of which one is known merely from 

 a single specimen. The following is a short synopsis : 



Coscoroha Eeichb. 

 = 1852. — Coscoroha Eeichb. Syst. Avium, p. x. 



= 1855.— " PsettrfoZor G. R. Gray, MSS." Catal. Gen. Subgen. Bird's Brit. Mus., p. 

 122. 

 = 1872.—PseuclocijcHus Sundev., Tent. Meth. Av. Disp. p. 147. 



Key to the specks : 

 a' Primaries with black tips; the nail of the bill flesh-colored ; feet red. 



1. Candida (Vieill.) 1816. 

 o* Primaries entirely white ; the nail of the bill black ; feet orange-colored. 

 2. davidi SwiNH. 1870. 



