16 



Order CETACEA. 

 Suborder MYSTACOCETI. 



Functional teeth arc wanting and the palate is provided with 

 baleen ; the cranium is symmetrical ; the nasals form a roof to the 

 narial passages ; and the tympanic is involuted and anchylosed to 

 the periotic. 



Family BAL.ENID^E. 

 This family includes all the members of the Suborder. 



A. BAL.ENINE SECTION. 



At least usually, some or all of the cervical vertebrae are anchy- 

 losed together. The tympanic is deep and angular, its inflation 

 comparatively slight, the involucrum 1 not fig-shaped, and frequently 

 with no well-marked depression at the anterior extremity of the 

 superior border of the inner surface for the eustachian canal. 



Genus BALJENA, Linn. 2 



Including Baleenula, Van Beneden s . 

 Bal&nutus, Van Beneden 4 . 



Pig. 6. 



Salcena myfticetus. The right tympanic of an immature individual, from the 

 inner (A) and outer (B) aspects ; recent. |. (From the ' Proc Zool. Soc.') 



1 This term may be applied to the reflected superior portion of the inner wall 

 of the bone. 



8 Syst. Nat. ed. 12, vol. i. p. 105 (1766). 

 8 Bull. Ac. R. Belg. ser. 2, vol. ixxiv. p. 11 (1872). 

 * Ibid. p. 13. 



