308 



PROF. HUXLEY ON THE ALECTOROMORPH^. [May 14, 



becomes larger in the Peristeromoi-phce and in many other birds, 

 the Musophagidce among the rest. 



The bones of the fore hmb in part resemble those of the Fowls, 

 and in part those of the Pigeons; while the humerus has a great 

 deal of resemblance to that of Gorythaix ; indeed it holds a midway 

 place between Gorythaix and Crax. The bones of the antibrachium 

 and the manus, on the other hand, are much nearer to those of the 

 Pigeons than they are to those of Corythaix. 



The pelvis (figs. 10 & II) is more like that of Coturnix than that 

 of Corythaix ; but, though it resembles both, it differs from both in 

 the absence of any ilio-pectineal process, and in the circumstance 

 that the ilio-sacral fossae are completely roofed over by bone. The 

 obturator foramen, as in many GaUinaceous birds, is not bounded 

 by bone behind ; in Corythaix it is. 



Fig. 11. 



Fig. 10. 



■>v 



Figs. 10 & 11. Lateral and dorsal view of the pelvis of Opisthacomus. 



The relative proportions and form of the femur and the tibia are 

 very nearly such as are observable in the ordinary Pigeons. The 

 metatarsus is longer in proportion to the tibia than in tbe ordinary 

 Pigeons, shorter than it is in Goura. 



The tarso-metatarsus itself (fig. 12, p. 309) very closely resembles 

 that of the Pigeons, though the form of the distal articular surface 

 of the metatarsal of the hallux is more like that of Crax. The 

 tarso-metatarsus of Corythaix is very different. 



The middle toe is considerably longer than the tarso-metatarsus, 

 and slightly longer than the femur. It is not so long as the femur 

 in any Gallinaceous bird, nor in Corythaix. In the ordinary Pigeons 

 it is considerably longer than the tarso-metatarsus ; in Corythaix 

 just as long. 



