ANATIDiE.] OSTEOLOGIA AVIUM. [ANATINiE. 



Furculum of moderate strength, with, a very slight process at the junction of the 

 rami. 



Coracoids long. 



Wing-bones of moderate length, but not nearly so long in proportion to the size of 

 the bird as in Dendrocygna. 



Leg-bones, Metatarsus with the calcineal ridge not carried down the back. 



Measurements. 



Tenths. 



Length of humerus . . . . , 38 



Length of ulna 34 



Length of metacarpus 21 



Length of femur 20 J 



Length of tibia 32 



Length of metatarsus 17 



Length of sternum 41 J 



Tenths. 



Breadth of posterior margin of sternum 20 

 Breadth of anterior margin of sternum 1 9 



Depth of keel 9 



Length of head . . . . : . . 45 



Breadth of head 12 



Length of pelvis 42 



Breadth of pelvis ..,.,. 18 



Dafilla, Leach. 



Acuta, Linn, 

 Similar in every respect, except in size, to Anas, 



Malacorhynchus, Sw. 



Membrinaccus, Lath. 



I have only some fragments of this genus taken from a skin. The bones of the 

 cranium are very light and thin, in comparison with Anas ; in shape, however, they 

 are very similar. 



I have also fragments of Querquedula, Creeca, and Erythorhyncha, all of which are 

 similar in form to Anas. 



Aix, Bote. 



Galericulata. 



Cranium broad between the upper edges of the orbits ; orbital septum perforated by 

 three foramina. Palatine bones broad posteriorly, and inclining outwards and down- 

 wards on their exterior margins ; a short central ridge united with the interarticular 

 bones, the anterior portion abruptly pointed on the inner edge ; foramen lacerum pos- 

 terius very large. 



Sternum with the anterior edge of the keel projecting much forwards, straight, and 

 not scolloped out. In other respects, except in size, similar to Anas, 

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