4?0 MR. F. E. BEDDABD ON INTEECENTBA IN BIRDS. [May 4, 



two fair-sized free intercentra followed by two liypoceutra. I 

 found exactly the same number of intercentra and hypocentra in 

 Thinocorus rumicivorus. In Ononis alba there are 8 free caudal 

 vertebrae, the fifth bears a small hypocentrum ; then follow two 

 free good-sized intercentra, of which the last is divided by a suture 

 into two parts. Finally, there is a large bifid hj^ocentrum. 



Intercentra are also present in the Laridae. In Stercorarius 

 antarcticus there are three small round button-shaped intercentra 

 increasing in size from before backwards, followed by two large 

 bifid hypocentra. 



Ealli ; Otides. 



So far as I have been able to ascertain, neither the Balli 

 (including Heliornis) nor the Otides possess free intercentra. 



COLUMB^. 



The same remark may be made concerning the Pigeons. 



ACCIPITRES. 



In Dryotriorchis spectahilis there is one free nodule of an inter- 

 centrum lying between the first two free caudals ; the remaining 

 vertebrae have strong hypocentra, which are bifid at the tip. In 

 other Hawks there are no free intercentra, but always hypocentra, 

 which are constantly bifid at the tip and sometimes chevrons. 



PSITTACI. 



I have found no free intercentra in any Parrot, but always a 

 certain number of hypocentra, which may or may not be bifid at 

 the tip. 



Opisthocomi. 



In a skeleton of the Hoatzin there are three free intercentra 

 gradually increasing in size, and two hypocentra following them. 



Galli. 



Intercentra appear to be rare in this group of birds. I found 

 no free intercentra anywhere, and only hypocentra on the last two 

 caudals of Aburria carunculata \ 



CTJCiriii. 



In DO Cuckoo that I have examined have I found any free 

 intercentra. But in all there are two or three hypocentra on 

 the last free caudals ; one or more is usually a chevron-bone, 

 i. e. perforated. 



^ In Crax glohicera, however (Parker, "On the Osteology of Gallinaceous 

 Birds, &c.," Tr. Zool. Soc. t. p. 169), there are two free intercentra (" hypo- 

 physes"). 



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