228 



long, for a portion has been broken from the anterior extremity, 

 probably 3 feet at least. The following are the gross dimensions : 



Total length of specimen . . . 16 ft. 4 in. 



Length of rami from point of divergence . 6 ft. 4 in. 



Breadth of same at widest portion of wing 2 ft. 2 in. 



Extent of expansion from one condyle to the 

 other . . . . . . 6 ft. 



Area of articulating surface of condyle 7 by 9 in. 



Circumference of horizontal bodies in appo- 

 sition . . . . . . 2 ft. 6 in. 



Length of tooth-furrow . . . .lift. 



The larger tooth sockets, of which but 19 remain, measure 7 

 inches in length, 34- in width, and 2^ in depth. 



As seen by the above measurements, the tooth-furrows are 

 continued up a foot upon the edge of the rami after their diver- 

 gence. On comparison with a young specimen exhibited, which 

 is 66 inches only in total length, and contains 25 teeth, we 

 see the alveolar process lying for the distance of 26 inches upon 

 the horizontal portion, and running 10 inches along the edge of 

 the rami. We conclude, therefore, that at this age a much larger 

 proportion of the teeth occupy this situation, and that with in- 

 creasing maturity and strength they pass forward, and are almost 

 wholly confined to the more advantageous situation of the body. , 



The teeth are conical, ovoid or flattened laterally, and more or 

 less pointed and worn according to age and usage. They curve . 

 forward and toward the median line, and, as is the case, with a sin- 

 gle exception, among all the cetacea, are implanted in the alveolar 

 process by a single root. While young they are conical, sharply 

 pointed, and much curved, presenting a reptilian appearance. 

 At this period they are hidden by the gum or project but slightly 

 from it, and in fact are retained in their place through life more 

 by the soft tissues than by any bony surrounding, so that a cabi- 

 net specimen containing teeth is seldom met with, as the liga- 

 mentous gum, when allowed to become dry, brings away with 

 itself, when removed, the whole series. The development of the 

 tooth matrix, analogous to the same process in fishes, goes on 

 within the gum, and is never inclosed by a bony cavity. Grad- 

 ually with age the alveolar process deepens ; the fang, still a hoi- 



