BEPORT ON THE SPHENISCID.^. 



39 



of the obturator foramen ; but here, as elsewhere, the two bones are united only by fibrous 

 membrane. In consequence of the divergence of the posterior extremities of the two pubic 

 bones, the posterior outlet of the pelvis is very wide, and well adapted to the passage of 

 the eggs, which in the Penguin, as in the majority of water birds, are of large size. 



As already observed, the pelvic bone does not anchylose with the lumbo-sacral portion 

 of the vertebral column in any species of Penguin. In them the pelvis is united to the 

 backbone by suture even in the adult bird. 



The pelvis presents essentially the same form in every species of Penguin. In 

 Aptenodytes and Pygosceles it is somewhat longer in comparison with its breadth than in 

 other species. 



The following are the dimensions of the pelvic bone of different species in inches : — 



The Femur. 



The femur in the Penguins differs but little from that of other birds. 



The head of the bone is globular in form, its upper surface being somewhat flat. The 

 depression for the attachment of the round ligament is of large size. The neck of the 

 bone is short and stout. As in other birds, its upper surface, as well as that of the 

 great trochanter, is covered with cartilage, to adapt it to the lower surface of the pelvic 

 '•' antitrochanter." The great trochanter, continuous with the shaft of the bone, is bounded 

 anteriorly and posteriorly by a prominent border. Of these the anterior is the more 



