12 Transactions. — Zoology. 



popliteal area is very broad, as in Pachyornis clephantopus 

 and E. ponderosa, but it differs from both in not having the 

 rough line along the inner side of the popliteal area broken by 

 a smooth groove ; the head also does not rise so rapidly as in 

 either of those species. 



The vertebrae show considerable differences from those of 

 P. clcphantopus, especially in the centra of the cervicals being 

 more compressed. These differences may be, perhaps, of 

 generic value ; but, until the skull is known with certainty > it 

 is better to keep it, as well as the next species, in Pachyornis. 



This species also occurred at Glenmark and at Hamilton's ; 

 but the typical form was not found at Enfield. There were, 

 however, a few specimens of a larger bird which, for the pre- 

 sent, I refer to this species, although it may probably be dis- 

 tinct. The metatarsus is 9 - oin. and the tibia 205in. in length. 

 The other dimensions will be found in the table at the end of 

 the paper. 



Pachyornis valgus. 



This species is founded on a pair of tibiae from Enfield, so 

 different from any others in the extraordinary internal expan- 

 sion of the distal end that I feel compelled to distinguish 

 them under a separate name. The dimensions are as follow :. 

 Length, 18'Oin. (457mm.) ; proximal width, 5'7in. (143mm.) ; 

 width of shaft, T7in. (43mm.) ; distal width, 3-3in. (84mm.). 

 This distal expansion of the tibia, nearly twice that of the 

 shaft, is not really greater than in the smaller species of 

 Dinornis, but it takes place so much more rapidly that it is 

 much more conspicuous. 



The metatarsus which I associate with these tibiae has a 

 length of 8-5in. (216mm.) ; the proximal width is 3-oin. 

 (89mm.) ; the width of the shaft, T9in. (48mm.) ; and the 

 distal width is 4 - 2in. (107mm.). It closely resembles the 

 same bone in E. crassus, and can only be distinguished from 

 it by the greater proximal width, necessary to articulate with 

 the expanded distal end of the tibia. A similar metatarsus is 

 in the collection from Glenmark, and there were one or two 

 in the Hamilton swamp, but I never before saw a tibia like 

 the present one. 



I have also temporarily placed here a pair of femora from 

 Enfield, very different from any others, and for which I can 

 find no other place. The length is llin. (279mm.) ; proximal 

 width, 4-0in. (101mm.) ; width of shaft, 2in. (51mm.) ; distal 

 width, 5-0in. (127mm.). They are specially remarkable for 

 the short head combined with a very stout shaft. 



