336 



UPPER LIP OF MANATEE 



CHAP. 



may get still more numerous. 

 This large number of grinding 

 teeth is obviously suggestive of 

 the Whales, with which the 

 Sirenia are believed by some to 

 be allied. It is at least a re- 

 markable coincidence that these 

 two aquatic groups of mammals 

 should both have assumed the 

 same indefinite tooth formula. 

 It is correct to say assumed, since 

 extinct forms of Manatees, such 

 as Halitherium and Prorastoma , 

 have not a continuous succession 

 of molars. The brain of the 

 Manatee is, contrary to the 

 usual arrangement among aqua- 

 tic mammals, smooth, and only 

 marked by one or two fissures. 



The Manatee ^ is black in 

 colour, its thick skin being 

 wrinkled. The animal is assisted 

 in feeding by a curious mechan- 

 ism of the upper lip ; this is split 

 in two, and the two halves, which 

 are furnished with strong bristles, 

 can play upon each other lil^e 

 the points of a pair of forceps. 

 The nippers are furnished with 

 nails, save in M. inunguis, but in 

 the nailed forms it is not every 

 finger which is thus armed. 



Halicore^ the Dugong, is an 

 entirely Oriental and Australian 



' Beddard, " Notes upon the Anatomy 

 of a Manatee (Ma iiatus inunguis)," Proc. 

 Zool. Soc. 1897, p. 47. 



^ See KUkenthal in Semon's " Zoolog. 

 Forschuiigen," Denkschr. Jen. 1897 ; 

 Langkavel, " Der Dugong, " .^ooZ. Garten,. 

 1896, p. 337. 



