AKT. 14. MARYLAND FOSSIL PORPOISE KELLOGG. 37 



Plate 2. 



Skull of Zarhachis flagellator Cope. Lateral views. Upper figure, Distal 

 end of rostrum ; Middle figure, Section of skull. Lower figure, Entire skull, 

 about Vo natural size. Abbreviations: Er pt., external pterygoid; Fo. inf., 

 infraorbital foramen; Max., maxilla; Pm.c, premaxilla ; Po. gl. p., postglenoid 

 process of squamosal ; Po. p., postorbital projection of frontal ; 8. or. pr., supra- 

 orbital process of frontal; V., vomer; Zyg., zygomatic process of squamosal. 



Plate 3. 



Mandibles of Zarhachis flagellator Cope. Upper figure, Ventral view of man- 

 dibles ; Lower figure, Dorsal view of mandibles. About Vs natural size. Abbre- 

 viations : Ang., angle ; C. condyle ; Cor. coronoid process. 



Plate 4. 



Skull of Zarhachis flagellator Cope. About % natural size. Lateral view, 

 showing external pterygoid and surrounding bones. Abbreviations : Ch., chan- 

 nel or shelf formed between external pterygoid and frontal ; Ex. pt., external 

 pterygoid ; Fo. inf., infraorbital foramen ; In. pt., internal pterygoid ; Max., 

 maxilla ; Max. dep., maxillary depression ; Po. gl. p., postglenoid process of 

 squamosal ; S. or. pr., supraorbital process of frontal ; V., vomer ; Zyg., zygo- 

 matic process of squamosal. 



Plate 5. 



Skull of Platanista gangetica Lebeck. About % natural size. Lateral view. 

 The external and internal pterygoids have been removed to show position of 

 the palatine. The right squamosal and its zygomatic process has also been 

 removed. Abbreviations : Bo., basioccipital ; Bs., basisphenoid ; C, condyle ; 

 Ex. 0., exoccipital ; Fo. inf., infraorbital foramen ; Fr., frontal ; In. pt., internal 

 pterygoid; Max., maxilla; Max. cr., maxillary crest; PI., Palatine; S. or. pr., 

 supraorbital process of frontal ; V., vomer. 



Plate G. 



Skull of Platanista gangetica Lebeck. About % natural size. Lateral view, 

 showing external pterygoids and surrounding bones. The right maxillary 

 crest has been removed. Abbreviations : Bo., basioccipital ; Bs., basisphenoid ; 

 C, condyle, Ex. o. exoccipital ; Ex. pt., external pterygoid ; Fo. inf., infra- 

 orbital foramen ; Fo. ov., foramen ovale : Fr., frontal ; In. pt., internal ptery- 

 goid ; Lac, socket for insertion of lachrymal; Max., maxilla; Max. or., maxil- 

 lary crest ; Po. gl. p., postglenoid process of squamosal ; S. or. pr., supraorbital 

 process of frontal ; Sq., squamosal ; V., vomer ; Zijg.. zygomatic process of 

 squamosal. 



Plate 7. 



Fig. 1, Left tympanic of Platanista gangetica Lebeck, Superior view ; 2, Left 

 t.vmpanic of Zarhachis flagellator Cope, Superior view; 3, Right tympanic of 

 Platanista gangetica Lebeck, Internal view; 4, Kight tympanic of Zarhachis 

 flagellator Cope, Internal view ; 5, Left periotic of Platanista gangetica Lebeck, 

 Inferior view ; 6, Left periotic of Zarhachis flagellator Cope, Inferior view, 

 posterior process missing; 7, Left periotic of Plantanista gangetica Lebeck, 

 Internal view; 8, Left periotic of Zarhachis flagellator Cope, Internal view, 

 posterior process missing. All figures about % natural size. 



