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NEW YORK STATE MUSEUM 



ities of the os furcula are long drawn out into acute points, and, as 

 in ducks usually, they are at right angles to the plane in which 

 the loop of the arch lies. The anterior half of the scapular blade 

 in this species is thick and strong. 



Oidemia perspicillata possesses a slender furcula with 

 a broad U-arch, that has the free posterior ends greatly compressed 

 transversely, and the processes on each, above, very distinct. A 

 scapula here is dilated at its distal end, and very thin; it is like- 

 wise truncated with its tip rounded off. A small epicoracoidal 

 apophysis is present upon either coracoid. In general, among the 

 Anatinae when the elements of the pectoral arch are articulated 

 in situ, the manner of their doing so is as we find it in N e 1 1 a 

 r u f i n a . Mesially, the coracoids do not quite meet each other 



in their sternal beds; either free dis- 

 tal end of a clavicle simply rests 

 against the inner aspect of the head 

 of the corresponding coracoid, while 

 its produced pointed extremity rides 

 well over on to the dorsal aspect of 

 the head of the scapula of its own 

 side. The scapulae reach nearly as 

 far back as the pelvis. The' long 

 axes of the coracoids are nearly in 

 the same plane in which lies the long 

 axis of the body of the sternum. 

 The scapulae articulate at right 

 angles with the coracoids, and a wide . 

 interval occurs between the anterior 

 carinal angle of the sternal keel, and 

 the mid posterior lower point of the arch of the furcula. Upon 

 the whole a pectoral girdle of this kind is one of great strength, 

 and is indicative of the ample powers of flight which the represen- 

 tatives of this suborder of birds are known to possess. 



The sternum affords another instance of skeletal similarity be- 

 tween the genus Spatula and the teals ; indeed, this bone in the lat- 

 ter genus is to all intents and purposes the perfect miniature of the 

 sternum as I find it in the first named genus of ducks [see fig. 24"]. 

 On its dorsal aspect the bone is much concaved throughout and 

 presents a single, median, pneumatic foramen just within its an- 

 terior border. This aperture, though a smaller one, is also seen 

 in the garrot, but the sternum of that duck is a nonpneumatic one. 



Fig. 23 The furcula ofSomateria 

 dresseri [Smithsonian Collec. spec. 

 16989]. Drawn, natural size, by the 

 author from the specimen 



