•112 JOURNAL, BOMBAY NATURAL HISTORY SOCIETY, Vol. XV. 



" Pterygoids divergent posteriorly. 



" Ribs eleven, the first five double-beaded. 



" Verfcebrw, C. 7 ; D. 11 ; L. 13 ; Ca. 18 = 49." 

 To this Mr. Ferguson adds that the teeth had not pierced the gum, and 

 that the specimen probably belongs to Solatia. 



As regards this generic identification, I quite agree with Mr. Fergu- 

 son. In this connection it is important to notice that Dr. Blanford, in 

 the " Fauna of British India, " has transferred the Indian species included 

 by Messrs. Flower and True in the (typically S. American fresh-water) 

 genus Sotalia to Steno ; remarking that " the differences between the 

 Indian generic types here brought together appear to me scarcely to 

 justify general distinction, until the skeletons are known. The typical 

 Sotalice are estuarial or fluviatila dolphins with 51 to 55 vertebrae." 



In this " lumping " Dr. Blanford appears to have considered that the 

 separation of the pterygoids in Soialia and their approximation in 

 Steno were not characters of generic importance. Neither did he attach 

 generic value to the more numerous (26 — 30), smaller, and smoother 

 teeth of the former as compared with the latter, in which the number 

 varies from 20 to 27. 



The fact that the skeleton under consideration, which belongs to a 

 species closely allied to one of those included by Dr. Blanford in Steno, 

 has the number of vertebrae even less than was previously known to be 

 the case in any species of Sotalii, renders it advisable to revert to the 

 view of Messrs. Flower and True. Nor is this all, for I find that, in 

 addition to the separation of the pterygoids, the oriental species of Sotalia 

 may be readily distinguished, at least in the young condition, by the form 

 of the palatines. For instance, in the Trevandrum skull the palatines 

 (pal.) form a kind of W-shaped band across the vomer, with a long 

 median suture quite clear of the pterygoids (Pt.) A precisely similar 

 condition obtains in the palate of Sotalia sinensis figured by Sir W. H. 

 Flower ( l ). On the other hand, in the palate of Steno, as figured by the 

 same observer ( 2 ), the W-like form of the palatines is not nearly so 

 marked, and there is no long symphysis of those bones below the line of 

 the pterygoids. 



The two genera may therefore be shortly distinguished as follows : — 



Sotalia. — Teeth medium, smooth, and numerous (26 — 35). Ptery- 

 goids separate. 



(O Proc. Zool. Soc. London, 1883, p, 487, fig. 7. 

 C) Ibid., p. 483, fig. 6. 



