Prof. Eschricht on the Gangetic Dolphin. 287 



the cornea — consequently a part of it not immediately connected 

 with sight — occupies an unusual extent of its circumference 

 (above one half in the greatest whales). But in comparison 

 with other marine mammalia, namely Seals, the eye of whales 

 must be called small, absolutely ; because in those the eye is very 

 large. It must accordingly be admitted as a proportionally sig- 

 nificant feature in physiological respects, to meet with a toothed 

 whale, not by any means of the small kinds, having an eye in 

 diameter not more than ] i'". Assuming — for as yet we can do 

 no more — that this little eye is constructed like that of Cetacea 

 in general, consequently with an extraordinarily thick cornea, it 

 must actually be ranked among the smallest in the class of Mam- 

 malia ; and taking further into account its relative measurement, 

 which is of less, but still of some weight on this occasion, the eye, 

 like that of the mole, decidedly points out that the usual abode 

 of the animal is void of solar light ; in which respect, my state- 

 ment of the smallness of the holes for the optic nerves, and the 

 presumed extreme smallness, or almost rudimentary state of the 

 optic nerves themselves, must be considered as decisive. 



Our dolphin occupies therefore, in anatomical respects, the 

 same place among whales, as the mole does among animals of 

 prey, and the subterranean rodentia among the order of Rodentia. 

 It now remains to find out whether this result corresponds with 

 our experience as to the mode of living of the animal. The 

 few and scanty communications of Lebeck and Roxburgh are 

 reiterated in the following manuscript notes of M. Reinhardt, 

 with additional not unimportant observations made by himself 

 and others. " According to Dr. Cantor, the Platanista makes its 

 appearance in the Hoogly at Calcutta only in the cold season 

 (corresponding to our autumn or winter) ; but he was unable to 

 state with certainty, whether it migrated after leaving that neigh- 

 bourhood, though he conjectured, and no doubt rightly, that it 

 is more probable it seeks the ocean than the higher parts of the 

 river. It swims singly or in pairs, not gregariously, and at the 

 time it makes its appearance in the Hoogly, it is by no means of 

 rare occurrence ; it is frequently observed to show a small part 

 of its body above the surface of the water, and then immediately 

 to dive down again. The animal is, however, rarely caught, by 

 entangling itself in fishing nets, and upon the whole it is very 

 difficult to obtain one. Mr. M'Clelland gives an account of a 

 singular manner in which two individuals were caught (Calcutta 

 Journal of Natural History, 1841, i. p. 425) ; namely in conse- 

 quence of blowing up the wreck of some ship which was obstruct- 

 ing the navigation of the Hoogly, the column of water raised at 

 the moment of explosion threw upon the shore two dolphins, a male 

 and a female, together with a large quantity of fish. The male 



