984 MR. W. p. PYCBAFT ON THE [DeC. 13, 



B. Vebtebe^. 



All the presyasacral vertebrae are free ; all the thoracic vertebrse are opiatho- 

 ccbIous ; all the cervicals, save the atlas and axis, have a bony carotid canal, 

 formed by an outgrowth from the lower surface of the anterior zygapophysis 

 which extends downwards to tlie capitulum of the cervical rib ; there are eight 

 caudals, not including the pygostyle, which is made up of about six vertebrae. 



Key to the Genera. 



A. Neural spines on 2-6 ; 5-9 with elongated cervical ribs ; 2-4 with 



moderately large hyperapophyses ; 12-14 with large metapophyses ; last 

 cervical and first dorsal with 1 to 3 bifurcate hypapophyses. Aptenodytcs. 



B. Cervicals 4-1 1 with elongated ribs, on 4 and 5 in P. fmniata extending 



back to the end of the centrum ; 2-5 with very long hyperapophyses ; 

 12-14 with much elongated metapophyses ; last cervical and first 4 

 thoracic vertebris with bifurcate hypapophyses Pygoscelis. 



C. Cervicals 4-9 with elongated ribs; 2-5 with elongated neural spines; 



2-8 with much elongated hyperapophyses decreasing from before 

 backwards ; 1 1-12 with elongated metapophyses ; first and second 

 thoracic vertebrre only with bilurcate hypapophyses Catarrhactes. 



D. Cervical ribs of 5-8 vertebrse only conspicuous ; in vertebras anterior 



and posterior to these, the rib scarcely projects beyond the lateral and 

 ventral laminae forming the carotid canal ; hyperapophyses on 3-6 ; 

 metapophyses of posterior cervicals (12-13) not greatly elongated ; 

 hypapophyses of last cervical and 1-3 thoracic vertebrae bifurcate. 



f Spheniscus. 

 \ Eudyptula. 

 The vertebral formula is:— 

 Ct. 13 ; Cv. th. 2 ; Th. 5+1 ; Lb. 4 ; Lb. sc. 4 ; Sc. 2 ; Cd. 1+9 =41. 



6 10 



C. Steenxtm and Pectoral Girblb. 



Corpus sterni half as broad as long, with a pair of notches posteriorly, a spina 

 externa, and with the keel projecting forwards beyond corpus sterni ; pre- 

 coracoid and acrocoracoid large ; scapula of great breadth and truncated 

 posteriorly. 



Key to the Genera. 



A. Length of coracoid equal to distance from anterior border of corpus sterni 



to the middle of the posterior lateral process ; lengdi of posterior lateral 

 process less than that of coracoid ; anterior border of keel projecting far 

 forwards Aptcnodytes. 



B. Length of coracoid less than the distance from anterior border of sternum 



to middle of posterior lateral process. 



a. Posterior lateral process equal to or longer than the coracoid ; supra- 



coracoid foramen rarely complete Pygoscelis. 



b. Posterior lateral process less than coracoid ; supraeoracoid foramen 



complete. 

 a' . Length of sternum more than 3 in. 



a". Posterior end of scapula truncated ' Catarrhactes. 



b". Posterior end of scapula rounded tipheuiseus. 



b' Length of sternum not exceeding 3 in Eudyptula. 



' The form of the scapula in C. chrysolophiis closely approaches that of 

 Spheniscus, from which genus the sternum and shoulder-girdle of this species 

 can be easily distinguished by reason of the great width across the posterior 

 lateral processes (see p. 978). 



