212 MB. F. DAT ON AMPHIBIOUS AND 



Fresliwater fishes, so far as I know, cannot live in the sea; it is 

 entirely unsuited for them ; and this is one reason for believing 

 that as Indian freshwater fishes are found in Ceylon, the Anda- 

 mans, and Nicobars, there must have been at one time a land con- 

 nexion, so that a freshwater continuity was possible. 



Limiting my remarks to the migrations of strictly freshwater 

 fishes in India, I think there are two subjects for consideration : — 



(1) Migrations as observed at monsoon-seasons. 



(2) Fishes falling from the clouds. 



The migrations of fishes at the commencement of monsoons 

 are due to two causes — breeding-purposes, and a search for food. 

 I do not propose entering upon the breeding of Indian freshwater 

 fishes here, as the subject would inordinately increase the length 

 of this paper ; I will therefore merely remark that certain marine 

 forms deposit their ova in the rivers of the plains, that many spe- 

 cies from the plains ascend hill- rivers and choose side-streams for 

 their ofi'spring, whilst most of the amphibious forms pass up small 

 watercourses and there deposit their ova. In short, the direct 

 aerial respiration of certain amphibious fishes is a provision to 

 enable those forms to migrate through moist grass and muddy 

 channels. jSTumerous examples are given in Sir E. Tennent's 

 ' Ceylon ' and elsewhere of migrations of these fishes. 



It is evident that as soon as the rains set in we find nature vevi- 

 vified in the East ; and with the vegetation animal life wakens up. 

 Insects and Invertebrates appear ; food that is suitable for fish 

 begins to abound. In tanks during the hot months the smaller 

 forms of fish have served for the nourishment of the large ones ; 

 but as the bivalves, univalves, and frogs make their appearance the 

 fish evidently begin to change their diet. Thus it is that at the 

 commencement of the rains fish become very excited ; apparently 

 dissatisfied with the localities they inhabit, they restlessly seek a 

 change. This may be owing to the same instinct which causes 

 the migration of marine fishes to the fresh waters ; or a change in 

 the state of the waters augments their appetite, and with such 

 arises the necessity of seeking a place where food more abounds. 



The second form of migration of fishes, or their suddenly ap- 

 pearing where they have not been previously observed and could 

 scarcely have existed, is one which deserves attention; and of this 

 we have two forms — (1) falling from the clouds, (2) appearing in 

 the plains or elsewhere after heavy rains. 



That fishes have been observed falling from the clouds has been 



