AXIAL SKELETON OF THE PELECANID^E. 367 



dorsally, owing to the breadth of the ilia; transverse diameter of pelvis between its 

 antitrochanteric processes nearly double the width of the most preaxial part of ilia ; 

 lateral acetabular fossa very large and quadrate ; a supraacetabular fossa ; pelvis of 

 moderate relative length ; postaxial half of external margin of ischium slightly convex ; 

 ventral surface of conjoined ischium and ilium extensive; ventral surface of ischium 

 slightly ridged ; isehium, external to obturator-foramen, narrow. Pygostyle curved, 

 convex dorsally, with its apex curved postaxiad and ventrad. The vertebral ribs have 

 generally uncinate processes, except the last; last sternal rib expanded proximally. 

 Sternum but little longer than broad ; lateral xiphoid processes narrow and pointed ; 

 pleurosteon wide, with five articular surfaces. 



SULA. 



Cervical vertebrae 15, cervico-dorsal 3, together 18 ; dorsal 6, lumbar 2-4, lumbo- 

 sacral 2 or 3, sacral 1 or 2, sacro-caudal 5 or 6 ; caudal, without pygostyle, 7 : total 

 43 or 44. Vertebral ribs 9, sternal ribs 6 or 7. Vertebrae generally but little swollen 

 or pneumatic ; styloid processes free, rather long and rather stout ; anterior cervical 

 vertebra? all short ; seventh and ninth bent dorsad from eighth ; hypapophyses of 

 first, second, third, and fourth vertebras large, and small ones to seventeenth and 

 eighteenth vertebree ; none present in posterior dorsal or lumbo-sacral region ; haemal 

 arches to vertebrae from the ninth or tenth to the thirteenth; no lateral ridges 

 beneath fifteenth to twenty-sixth vertebrae ; ridges and processes generally sharp ; 

 metapophyses relatively very large. Atlas with an odontoid foramen and bony hypa- 

 pophysis ; axis with very long hypapophysis, large hyperapophyses, and lateral foramen 

 leading into centrum ; third vertebra with very long hypapophysis, short and wide 

 lateral vertebral canal, much larger hyperapophyses than in Pelecanus, and very 

 marked interzygapophysial ridges ; fifth and sixth vertebra? with a median subcentral 

 groove ; postzygapophyses of seventh vertebra not more postaxiad than those of sixth ; 

 postaxial margin of neural arch of seventh vertebra not very concave, the first (pre- 

 axially) deeply concave behind being that of the eighth vertebra. Eighth vertebra 

 more pressed back preaxially than the seventh of Pelecanus, but less so than the 

 eighth of Pelecanus ; it is the first which is pressed back preaxially ; eighth vertebra 

 about as long as the seventh, with no haemal arch, but with prominent metapophyses ; 

 styloid processes rather larger than in the seventh vertebra, which has its praezygapophyses 

 slightly more preaxiad, and postzygapophyses decidedly more postaxiad than centrum. 

 Ninth vertebra much more pressed back preaxially than the eighth, and the first one 

 very much pressed back, and in its development intermediate between the eighth and 

 the ninth vertebrae of Pelecanus ; its neural spine much more developed than that of 

 the eighth vertebra generally, with no ha3mal arch ; its hyperapophyses two sharp 

 lateral processes ; neural spine most prominent in the ninth vertebra of all the cervical 

 vertebrae ; its metapophyses very long and sharp processes. Tenth vertebra with a 



