THE BAL^NOIDEA. 



397 



imites only witli the first rib, and tlie union is direct, so 

 tliat tliere are no sternocostal ribs. 



Fig. 105. 



Fig. 105.- — " Ear bones" of the adult BakEtia australis. Seen from 

 within in the upper figure ; from without in the lower. Eu., Eus- 

 tachian canal; Au., external auditory meatus; Sty., ossified root 

 of the styloid process. 



The skull (Fig. 104) is exceedingly large in proportion to 

 the body, and nearly symmetrical. The nasal bones, Na., 

 thotigh short, are longer, and more like those of ordinary 

 mammals, than is the case in other Cetacea. The maxilla, 

 Mx., extends outwards in front of the great supraorbital 

 process of the frontal, Fr., but it does not cover the frontal 

 bone. There is a distinct lachrymal. Each ramus of the 

 mandible, Mn., is convex outwards and concave inwards; 



