XII.] 



CETACEA. 



197 



posed between the antorbital processes of the frontal and 

 maxilla and the malar. 



The palate is long and narrow, with a strong keel or 

 ridge in the middle line. The surface on each side, sloping 

 upwards and outwards, is perforated by many large foramina 

 to permit the passage of blood-vessels and nerves to the 

 matrix of the baleen, or " whalebone," which covers it in 

 the living animal. It is chiefly formed by the maxilla, 

 behind which are large palatines and very small and widely 

 separated pterygoids. 



Fr 



r iG. 63. — Section of the skull of a fcetal Southern Right Whale (Baltzna australis), ft . 

 PMx premaxilla ; Na nasal ; Fr frontal ; Pa parietal ; SO supraoccipital ; OS 

 orbitosphenoid ; AS alisphenoid ; EscO exoccipital ; Per periotic ; BO basi- 

 occipital ; Ty tympanic ; BS basisphenoid ; Sq glenoid articular surface of squa- 

 mosal ; Pt pterygoid ; PI palatine ; PS presphenoid ; Vo vomer ; M x maxilla ; 

 cp coronoid process of mandible ; cd condyle ; dg dental groove ; mg remains of 

 groove which lodged Meckel's cartilage. No part of the mesethmoid is ossified. 



The zygomatic process of the squamosal is an immense 



■ihedral pillar in Balcena, having the large shallow glenoid 



fossa on its under surface removed considerably from the 



niddle of the cranium, so as to give sufficient width to the 



