Carinate Birds from Central Madagascar. 351 



with certainty to this species ; even if this method of identi- 

 fication liad been impossible, the great number of specimens 

 of this particular type of metatarsus would be strong evi- 

 dence that they belonged to this, the commonest species. 



If only the wing-bones had been preserved, this bird 

 would probably have been regarded merely as a somewhat 

 robust variety of Sarcidiornis, a genus now occurring in 

 Madagascar. The skull and metatarsus, how-ever, show^ that 

 this is not the case, but that we are dealing wuth a bird 

 closely allied to, if not identical with, the Egyptian Goose, 

 Chenalopex (Bgyptiacus. This species is widely distributed 

 in Africa, but has never been recorded from Madagascar so 

 far as I can ascertain. Considering the great abundance of 

 the fossil remains of this, or at least a closely allied species, 

 in these comparatively recent deposits, the complete absence 

 of such a bird from the present avifauna of the island is 

 remarkable. It is also noteworthy that no bones that can 

 be referred to Sarcidiornis melanonotus, now a common 

 species, occur among the fossils, so that it seems that this 

 species must be of late introduction and that it has suc- 

 ceeded in displacing the older Chenalopex-\\ke type. 



The various specimens which I refer to the present species 

 indicate that it was subject to considerable variation in size, 

 and that, as in Chenalopex cegyptiacus, the differences were 

 partly dependent on sex, the male being larger than the 

 female. Some of the measurements given below will show 

 that this was the case. 



It will be unnecessary to give a complete description of 

 this species, but will be sufficient to point out the chief 

 characters in which it differs from Sarcidiornis melanonotus 

 and approaches Chenalopex eegyptiacus. 



The skull (Plate IX. fig. 1) . Of the skull of the type specimen 

 the w^hole of the cranial region together with fragments of the 

 facial portion are preserved. Comparison with the crania of 

 Sarcidiornis and Chenalopex shows at once that the fossil differs 

 widely from the former and approaches the latter in a number 

 of structural points, the chief of which are : (1) the shortness 

 of the postorbital part of the cranium ; (2) the narrowness of 



