SIRENIA AND CETACEA. 



311 



genus the general conformation of the skeleton is like that 

 of Manatus, though with some points of relationship to the 

 Dugongs. One of the most remarkable features in the 

 skeleton is the presence of a rudimentary femur, no other 



Fig. 61S.— Mounted skeleton of HalitherUim iu the Heidelberg University Museum. 

 (After Murie.) 



bones belongino; to the hincl-limb having been hitherto dis- 



CO o 



covered. As regards the dentition, there are tusk-like upper 

 incisors (as in Halicore), combined with enamelled molars (as 

 in Manatus). The molars are five or six in number on each 

 side of each jaw, and the anterior ones seem to have had 

 vertical successors. The posterior molars are two- or three- 

 rooted, with complex crowns, the pattern of which reminds 

 one of the corresponding teeth in Hi^piwpotarmis (fig. 619). 



Fig. 619. — Tug of the lo\^er niolais ol Halitherium Ciimeri, viewed from above. 

 Miocene Tertiary. (After Blainville.) 



The genus Felsinotheriuiii of the Tertiary of the Soutli of 

 Europe is closely allied to Holitherium, and has five molars 

 on each side of each jaw. Crassitheriuin, from the Pliocene 

 of Beloium, is so called from the thick walls of its skull, and 

 is supposed to be allied to Rhytina. Lastly, the remains of 



