TOOTHED WHALES 179 



existing Odontocetes can be derived from some such 



o 



original form. 



There are other facts which point in the same 

 direction. 



Not merely is the freedom from any trace of fusion 

 a character in which the cervical region of the 

 vertebral column may be considered to present 

 primitive characters for the mere freedom of these 

 vertebrae is found in other whales, both toothed and 

 whalebone (e-g-, Monodon, Baltznoptera) but the 

 great length of this region of the body is important. 

 There is in this Cetacean (and in Platanista) a 

 distinct neck. The atlas vertebra too is more 

 typically mammalian-looking than in other whales, 

 and the second vertebra has a better odontoid process 

 than is found elsewhere. 



But Inia is very far from being an ideal basal form, 

 with which to commence the Odontocete series. Its 

 teeth are extremely numerous, though possessing, 

 indeed, an additional cusp ; the sternum may be like 

 that of the Manatee, but is not typically mammalian 

 (it has been pointed out that the Sirenia are not 

 ancestral whales) ; the reduced lumbar region is 

 against the present view of the position of Inia. 

 There are, moreover, other facts which will be found 

 referred to under the description of this whale. Still 

 one cannot, at any rate in the present state of our 

 knowledge, get much nearer to the basal Odontocete. 



But this seems to bring us no nearer to the origin 

 of the whalebone whales. The most primitive type 

 of the latter seems to be the little Neobalezna. (See 



