Tetraonidje.] osteologia avium. [Odontophorinje. 



Bonasa, Steph. 



Sylvestris, Brehm. 



Cranium similar to Tetrao in general shape, but having the palatine bones more 

 arched outwards. 



Leg-bones. Accessory metatarsal extending upwards, but very slightly twisted; 

 calcineal ridge very small. 



Odontophorus, Vieill. 



Nigricollis, Gould. 



I have only the sternum and pelvis of this bird, both of which agree in shape with 

 the other Tetraonidce, except that the two fissures next the body of the sternum are very- 

 large and deep ; and there is scarcely a trace of the outer fissures, the splint bounding 

 them being very short. 



Perdix, Briss. 



Cinerea, Linn. 



Cranium rounded; occipital ridge very large. Palatine bones flattened perpendicu- 

 larly, expanded at their junction with the interarticular bones, and almost touching one 

 another. Orbital septum with three foramina ; nostrils large, rounded. 



Pelvis much narrower in proportion to its length than in Tetrao ; the central 

 depression at the junction of the ilium, with the vertebrae very deep. Ischiadic 

 foramen rounded ; no obturator foramen is apparent. 



Sternum with the internal fissures very large, and a slight notch near their anterior 

 extremities ; the central portion of the sternum very narrow ; splints bounding the 

 outer cavity short, and expanded at their extremities ; anterior edge of the keel very 

 much excavated. The remainder of the bones similar to Tetrao. 



Measurements. 



Tenths. 



Length of humerus ..... 20 



Length of ulna 19 



Length of metacarpus 10 



Length of femur 22 



Length of tibia 32 



Length of metatarsus ..... 21 



Length of sternum ...... 3| 



Tenths. 



Breadth of posterior margin of sternum 10 

 Breadth of anterior margin of sternum 8 



Depth of keel . 6J 



Length of head 19 



Breadth of head 10 



Length of pelvis 24 



Breadth of pelvis 10 



Francolinus, Steph. 



Capensis, Gm. 



Cranium similar to Perdix, but with the nostrils more oval. Palatine bones similar* 

 but much flattened laterally, 

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