DISCOVERIES IN AVIAN PALAEONTOLOGY. 405 



the only avian coracoid which at all resembles the fossil in the 

 form of its upper end is, I believe, that of Aptornis. The 

 wing-bones are very small in proportion to the size of the 

 bird, but, at the same time, are stout and strong ; the ulna 

 bears a number of tubercles marking the points of insertion 

 of the secondaries. The pelvis is long and narrow, but in 

 the posterior half, at any rate, it has been somewhat crushed, 

 so that in fact it is broader than would appear from Ame- 

 ghino's figure. The hind limb is long and comparatively 

 slender ; in the tibia there was a bony extensor bridge, and 

 in the metatarsus the hypotarsus is simple. All the above 

 details are taken from the skeleton of a single individual of 

 the smaller species, Phororhacos inflatus, in which the skull 

 is about thirteen inches long. In these birds the head is 

 proportionately very large, and this species probably only 

 stood about three feet high at the middle of the back. 

 Phororhacos longissimus is about twice as large, the skull 

 being two feet long and about ten inches high. Of the 

 other genera Pelecyomis is the best defined, the pelvis and 

 most of the limb bones being known. As already mentioned 

 this genus was placed by Moreno and Mercerat among the 

 Cat hart idee : and though there is little doubt that this is 

 incorrect, it is by no means clear that Ameghino is justified 

 in placing it in the Phororhacidce, the pelvis being strikingly 

 different from that of Phororhacos and the wing proportion- 

 ately so much larger that it was probably still efficient as an 

 organ of flight. The other genera of the family are for the 

 most part known only from mere fragments of limb bones. 

 Brontornis is a much larger and more heavily built bird than 

 the largest species of Phororhacos, and Opisthodactylus is 

 chiefly remarkable for the peculiar position in which Ame- 

 ghino supposes the hind toe to have articulated with the tarso- 

 metatarsus. In this paper also several extinct Penguins 

 are described, as well as a number of ordinary Carinate 

 birds belonging to several families. 



Lydekker points out (14) that the age of the deposits in 

 which these avian remains are found is probably much over- 

 estimated by the South American writers, and that they are 

 probably Miocene. He also discusses the relationship be- 



