404 BULLETIN OF THE UNITED STATES FISH COMMISSION. 



with an extra boat and two first-class spawn-takers, to assist the steamer 

 Lookout. The launch, under Cockswain Cleaveland, left on May 28, 

 and returned June 7. 



Pool experiments.— The experiment attempted in previous years 

 of confining unripe shad in the pool until they had become sufficiently 

 "soft" to yield spawn, was repeated this season, but with little or no 

 success. 



Several seine hauls offish were turned into the pool, and at intervals 

 the shad would be removed and examined. Most of those captured 

 proved "hard "or "rotten ripe," and but a very small number of eggs 

 was obtained from this source. The few eggs taken had the appear- 

 ance of being sound and healthy at the time of stripping, but soon 

 after being placed in the hatching jars,, would form into knots. No 

 iish were produced from the eggs thus obtained, and I again advance 

 the opinion that this experiment is not practicable. The shad are un- 

 used to a confined space like the pool, and are eager to escape. Failing 

 in this, they become frightened and rush against the sides of the pool 

 and the wire grating of the gates, bruising themselves severely, causing 

 the appearance of fungus, and afterwards death. Probably another 

 cause of failure this season was the presence in the pool of herring in 

 such large numbers. Their continual agitation stirred up the mud and 

 sediment on the bottom, and the sliming of the water, in addition, made 

 it extremely unwholesome, large numbers of fish dying daily. 



Another and dangerous feature was noticed in this connection. The 

 water used in the jars for hatching purposes was pumped from this pool 

 Mito the two large tanks in the water-tower, whence it passed through 

 pipes into the hatching house. About the lSth of May, when the pool 

 was crowded with shad and herring, it was noticed by the attendants 

 of the hatching house that the water was flowing less freely, and the 

 eggs began to present a dirty and sickly appearance. A prompt in- 

 vestigation showed that the water contained large quantities of dirt 

 and slime caused by the fish in the pool. The water was immediately 

 turned off and the pipes and jars thoroughly cleaned. It was pro- 

 posed to remedy this evil by running a new suction pipe outside of the 

 pool, and sufficient pipe for the purpose was ordered ; before it arrived, 

 however, the condition of the eggs became such as to make it imper- 

 ative that the cause of this pollution should be removed. Accordingly, 

 >u my earnest recommendation, the assistant commissioner instructed 

 t hat the pool gates be opened and the fish allowed to escape. This was 

 done at once, and in a short time, the eggs resumed their normal con- 

 dition. 



The experiments designed with the pool were thus practically ended 

 lor this season, as the catch of fish after the opening of the gates was 

 so small that the seine was stopped a few days after. 



By judicious management and untiring application on the part of 



