BULLETIN OF THE UNITED STATES FISH COMMISSION. 3G7 



to have decreased, as the smelt have increased. The yield of fish of 

 the Pestow Lake is the same as it was in former times, which proves 

 that no sheet of water caii produce more fish than is determined by its 

 quantity of suitable fish-food. 



As a correction of and addition to Professor Grimm's report re- 

 specting the persevering attempts, to transfer the Coregonus to the river 

 Wolga, by transferring young Coregonus from Nikolsk to Lake Seliger, 

 which is connected with the Wolga, I take the liberty to state, as I 

 have been informed by Professor Grinim, that no Coregonus whatever 

 are found in Lake Seliger, and that, so far at least, they have not 

 been acclimatized in the Wolga. It seems to be certain that the Wolga 

 Coregonus mentioned by W T assiltschikoff as fouud in the neighborhood 

 of Nischnij Nowgorod, are no Coregonus but grayling. As regards the 

 results of the transfer from Nikolsk of young fish and impregnated 

 eggs of Coregonus and trout, which has been made every year since 1870, 

 Professor Grimm could not give me any further information than that 

 a trout-hatching establishment near Moscow, which got its fish from 

 Nikolsk, had been reasonably successful, and that the experiment of 

 stocking a small pond near St. Petersburg with young trout, made by 

 an employe of the Museum of Agriculture and a farmer of the neighbor- 

 hood, yielded a few hundred roubles the first year after the fish had 

 been placed in said pond, but that during the following year the experi- 

 ment proved an entire failure. It is probable that the trout-food in 

 this pond had been used up during the first year, and that, as usual, it 

 was difficult to renew it. 



Professor Grimm informed me that he had made an interesting ex- 

 periment with sterlet, which I feel it my duty to communicate here. 

 During the years 1869-1871, 120 young sterlet had been brought to 

 Nikolsk and placed partly in Lake Pestow and partly in the ponds 

 belonging to the establishment. These fish grew and flourished till 

 they had reached their natural size, but they never spawned, and none of 

 them had either roe or milt during all the time they were at Nikolsk. 

 The observation is said to have been made in Russia, especially in some 

 convents, that this fish is not capable of propagation in lakes or ponds 

 or in stagnant water. The sterlet is a genuine river-fish, which only 

 propagates its species in rapidly flowing water. It spawns in spring, 

 after the water in the rivers and streams begins to fall, and its eggs, 

 which adhere to stones and other objects, are said to develop in an in- 

 credible short time, viz, four days. It seems, therefore, that it is exceed- 

 ingly difficult to transplant this fish by means of the transferring of im- 

 pregnated eggs. It is said, on the other hand, that young sterlets can 

 easily be transported a considerable distance ; they can be bought at a 

 reasonable price at Samara from Messrs. Mjiisniskoff and Tischinskij (see 

 the "Golos" No. 311, November 15, 1882). In view of the high price 

 of these fish Professor Grimm intends to devote himself, in future more 

 than heretofore, to the raising of sterlets in the Nikolsk ponds, because, 



