1839.] In dian Cyprinidce. 653 



not require more than a year or two at the utmost to arrive at 

 perfection. Beyond a single species of Gobio, and a single one of 

 the larger species already mentioned, more ought not to be introduced 

 to the same water, or allowed to exist in it, from the danger of their 

 proving inimical to each other, a point which I presume has never 

 been attended to sufficiently in attempts hitherto made to propagate 

 fishes ; hence, perhaps, the want of that degree of success which no 

 doubt would have rendered a practice so simple and beneficial, long 

 since universal. 



" The only alteration in the present form of the reservoirs, to adapt 

 them to the purposes in view, would be to enclose the lowest portions 

 of the bottom of each with stakes long enough to reach above the 

 highest surface of the water, and close enough together to prevent 

 the entrance of crocodiles, otters, and the like, should any such exist in 

 the neighborhood. The spawning season of the Ruee and other 

 Cirrhins, appears to be in the dry weather ; the contrivance here 

 suggested would therefore protect them at that time, and if there 

 should be any danger of the whole of the water drying up, wells of 

 sufficient size and depth might be formed within the enclosure, to 

 which the fishes would retire during droughts, while the shallow 

 waters around the wells would afford space enough for the deposit of 

 spawn. 



" Much of our success would depend on keeping these enclosures 

 as free as possible from all but the species we desire to propagate. 

 At the commencement of the dry season, before the fish begin to enter 

 the enclosure, the interval between the stakes might be closed with 

 straw, and as the water becomes sufficiently low without, most of 

 the rapacious kinds may be removed or destroyed ; none should be 

 allowed to remain, but that species alone which may be the object 

 of our care. This done, the only further attention necessary, would 

 be to save the fish in the enclosure from birds during the remainder of 

 the dry season. 



" Should our success be complete, from every moderately sized female 

 Ruee we should have on the commencement of the rains from five 

 to ten hundred thousand fry, which, as the waters rise would be quite 

 able to take care of themselves till the next season, when it would 

 be necessary again to destroy the rapacious kinds, as before. 



" The repair of the car ays* of Mysore, is said by Buchanan, to be 



* Such is the name by which the reservoirs are known in Southern India when kept 

 up for irrigation. 



