124 GILL, SYNOPSIS OF THE 



6. Postorbital process and zygomatic process of 

 squamosal connected. Frontal with a little 

 developed ante-orbital tubercle. Maxillary 

 contracted, with a crest and free margin over 

 suborbital region. PONTOPORIIN.E. 



2. Maxillary bones with large bony incurved crests. 

 Teeth without cingulum or tubercles. (Visual 

 organs rudimentary. External respiratory appara- 

 tus longitudinal.) PLATANISTIN-*:. 



IV. DELPHINrD^E Flower. 



SUBFAMILIES. 



1. Digits with not more than 4-5 phalanges to each. 



a. Cervical vertebrae all distinct. DKLPHINAPTERIN^E. 



6. Cervical vertebrae more or less (2 to 7) consol- 

 idated. DELPHININJE. 



2. Digits with numerous phalanges. GLOBIOCEPHALIN.E. 



V. ZIPHIID.E Gray. 



SUBFAMILIES. 



I. Maxillaries with no incurved lateral crests. ZIPHIIN^:. 



II. Maxillaries with greatly developed incurved crests. ANANARCIN^E. 



VI. PHYSETERID^E Gray. 

 SUBFAMILIES. 



1. Head very large, truncated in front. Blow-hole near 



the edge of the snout. Cerebral cavity declining 

 downwards. Jugal and zygomatic process of squa- 

 mosal connected. PHYSETERIN^E. 



2. Head moderate, conic in front. Blow-hole frontal. 



Cerebral cavity inclining upwards. Jugals and 



zygomatic processes of squamosals remote. KOGHN^E. 



VII. RHABDOSTEID^ Gill. 



MYSTICETE. 



I. Cervical vertebrae separated in whole or in part. 



DigifS 4. BAL^ENOPTERID^E. (VII.) 



II. Cervical vertebrae coalesced. Digits 5. BAluENnxE. (IX.) 



VIII. BAL.ENOPTERIDJE Gray. 



SUBFAMILIES. 

 I. Throat not plicated. Dorsal fin null. AGAPHELIX.E. 



