DOLPHINS FROM TRAVANCORE. 735 



With regard to the two specimens from Trevandrum, figured in the " Journal 

 of the Bombay Society" as T. fergmoni and T. catatonia, I am inclined to- 

 think that the former is the immature form of the latter*, despite the difference 

 in the number of the dorso-lumbar vertebra;'}". Now, if colour be worth any- 

 thing in this matter (and if it be not, we have practically nothing to 

 go upon), the type of fergusoni cannot be identical with the specimen here 

 referred to abusalam, as both are immature specimens. Moreover, the speci- 

 mens described as fergusoni and catatonia differ from abusalam (type and 

 young) by the general colour of the upper-parts being dark slaty instead of 

 greenish (when the skin is dry) and in the orange tinge of the under-parts. 

 Accordingly, if both the former belong to catatonia (and I have practically no 

 doubt as to the correctness of the identification of the adult), that species would 

 appear to be distinct from abusalam. In addition to the difference of colour, 

 it would seem to have fewer teeth and one caudal vertebra less. 



Turning now to the specimen represented in Plate XIII, Fig. 1., it might appear 

 at first that this is the adult of the one figured in Fig. 2 of the same Plate, if 

 we could assume the disappearance of the light under-parts with age. In the 

 first place, there is, however, no evidence that such a change takes place in 

 this group of Dolphins ; in the second place, the specimen in Fig. 1 was 

 accompanied by a younger example which had the same coloration ; and, in 

 the third place, the adults of both T. abusalam and T. catatonia have light 

 under-parts, as is also the case with T. tursio. 



Accordingly, it would appear that the Dolphin shown in Fig. 1 of the Plate, 

 which is certainly a Tursiops, is distinct from these three species. Now the 

 only member of the genus, which is wholly black, with the under-parts 

 somewhat lightened, is T. gilli, of the Pacific coast of North America, described 

 on the evidence of the skull, and only known in the flesh by " momen- 

 tary observations, " taken by Scammon. If this evidence be trustworthy, I 

 cannot separate the Trevandrum specimen from T. gilli , so far as colour is 

 concerned. 



As regards the number of the teeth, tbis is less in the type mandible of gilli 

 which is immature, and also in an aged skull ; and it is possible that in 

 the one case the full number may not have appeared, and that in the 

 other some may have been lost. In any case, the difference is not very great or 

 important. 



That a North-Pacific Dolphin should be met with on the coasts of India 

 is little, if at all, more improbable than the occurrence there of an Australian 

 form {T. catatonia'). Accordingly (till evidence to the contrary be forthcoming) 

 I propose to regard the specimen represented in Plate XIII, Fig. 1 as T. gilli. 



If I am right in the foregoing identifications (and the difficulty of the subject 

 is so great that every determination must be regarded as more or less pro- 



* I had not the figure of T. fargusoni when describing T. catatonia. 



f Differences in the number of dorso-lumbar vertebra in several species of Dolphin are- 

 noticed in Mr. True's memoir. 



