SPHENISOI 401 



coracoid in both is very long. The furcula is strong and 

 U-shaped. 



The bones of the anterior extremity are extraordinarily 

 flattened, in aiccordance with the paddle-like function of the 

 limb. 



The sternum is roughly triangular, with a well-developed 

 keel. There are two lateral notches (one on each side), 

 which are united distally by cartilage and membrane. There 

 is a spina externa, but no spina interna. 



The pelvis, unlike what is found in the majority of birds, 

 is remarkable for the fact that the pubes take a share in the 

 formation of the acetabulum. The ilia are well separated 

 from each other by the neural spines of the dorsal vertebrae. 

 The pelvis is thus perfectly free from, not ankylosed to, the 

 vertebral column. 



The point of chief interest in the hind limb of this group 

 is the imperfect fusion between the short metatarsals, which 

 closely resemble those of the dinosaur Ceratosaurus. The 

 only recent bird which approaches the penguins in the 

 shortness of these bones is Fregata. 



Fossil penguins are the genera Palaeudyptes and Pala- 

 spheniscus. The latter, from the Tertiaries of New Zealand, 

 was originally described by Huxley,' and later by Hectoe.^ 

 It was a large bird standing some five feet in height, the 

 recent birds not being larger than three feet. The wings 

 were proportionately longer than in recent birds, while the 

 partly separate metatarsals were as is the case now ; hence 

 this latter character is obviously an inherited one in the 

 recent penguins. 



The affinities of the penguins are not clear. This is due 

 to their antiquity, the existing characters of the group having 

 been apparently acquired in the Tertiary period. The main 

 facts of structure in which the penguins differ from other 

 birds are — 



(1) Continuous feathering (except Ghauna) . 



' ' On a Fossil Bird . . . from New Zealand,' Q. 3. Geol Soc. 1859, p. 670 

 '' ' On the Remains of a Gigantic Penguin,' Trans. New Zealand Inst. 1871, 

 p. 341. ' Further Notice of Bones of a Fossil Penguin,' &c., ibid. 1872, p. 488. 



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