I2IO 



THE CETACEANS 



its presence can easily be detected, without its being seen, by the blowing sound 

 it makes when it rises to breathe; but, during the rains, the rush of water 

 effectually drowns this means of becoming aware of its existence. ' ' This dolphin has 

 been obtained one thousand miles above Calcutta; and its upward range appears to be 

 only checked by the presence of rocky barriers and the diminishing depth of the water 

 of the river, aided perhaps by the increasing lowness of the temperature of the latter. 

 Although this Cetacean does not collect in herds, several individuals may often 

 be observed within a small area in the more placid reaches of the Indian rivers. 

 Dr. Anderson writes that " it is difficult to say whether the Gangetic dolphin con- 

 fines itself to limited areas when there is no disturbing cause at work, such as the 

 rains, leading it to disperse itself over other channels and branches of the river, which 

 are not accessible to it in the dry weather. In rising to breathe, the platanista may 



THE GANGETIC DOLPHIN. 



either simply expose the upper surface of its head sufficiently to bring its blowhole 

 above water, or, what is more common, plunge out of the water, upward, forward," 

 and downward, first exhibiting its long snout, followed by two-thirds of its back. At 

 such times it emits a short, blowing sound, which doubtless has given rise to the 

 term [susu] generally applied to it along the Ganges and Brahmaputra. During the 

 cold months, in the quiet reaches, it even becomes at times extravagant in its move- 

 ments, and will leap altogether out of the water with the tail curved downward. 

 As a rule, however, its respiratory visits to the surface are leisurely executed. I 

 have had the rare opportunity of narrowly observing the respiratory movements of 

 this dolphin from having had one alive for ten days in captivity. In its place of 

 confinement this individual rose slowly to the surface, exposing the blowhole and a 

 portion of its back. The blowhole opened whenever it reached the surface of the 



