CYPSELIDiE.] 



OSTEOLOGIA AVIUM. 



Measurements. 



[CyPSELINJB. 



Tenths. 



Length of humerus ..... 5 



Length of ulna 8 



Length of metacarpus ..... 9 



Length of femur 8 



Length of tibia 10 



Length of metatarsus 5J 



Length of sternum 12 



Tenths. 

 Breadth of posterior margin of sternum 8 

 Breadth of anterior margin of sternum 5 



Depth of keel 5£ 



Length of head 12^- 



Breadth of head 7-J- 



Length of pelvis 12 



Breadth of pelvis * 7 



Acanthylis, Boie. 



Nudipes, Hodgs. 

 The body is in the British Museum : similar to Cypselus. 



Tenths. 

 Length of humerus . 

 Length of ulna . . 

 Length of radius 

 Length of metacarpus 



Length of femur 

 Length of tibia . . 

 Length of metatarsus 

 Length of sternum . 



17 



Tenths. 

 Breadth of posterior margin of sternum 10 

 Breadth of anterior margin of sternum 7 



Depth of keel 6£ 



Length of head 



Breadth of head 



Length of pelvis 15 



Breadth of pelvis 9 



Numbering of the Vertebrae and Bibs of Volitoees. 





Cervical. 



Dorsal. 



Sacral. 



Caudal. 



True ribs. 



False ribs. 



Patagona gigas 



Thaumast ura vesper 



12 

 12 

 12 



9 

 9 

 9 



9 

 8 

 9 



6 

 6 

 6 



7 



7 

 7 



2 

 2 



2 



Cypselus apus 





General Bemarlcs on Volitoees. 



The whole structure of this Order is very remarkable. Throughout the Trochilidce a 

 remarkable similarity prevails in the skeletons, so as to render the description of more 

 than one unnecessary, the only differences being those of measurement. I had some 

 doubts at first whether or not to place the Cypselidw in this Order ; but this family 

 differs so much from the members of any other Order, and agrees in so many particulars 

 with the Trochilidce, that I have little doubt that they properly belong to this. The 

 structure of the wing, the great depth of the keel of the sternum and its being so very 

 much narrowed in front, the broad pelvis, and the position of the ischium and os pubis, 

 will at once distinguish the birds forming this Order from those of any other. 



c2 39 



