THE SMELTS 
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he small size and adhesive nature of the eggs, they are liable to form into clusters 
after being installed in the jars. This difficulty may be overcome by emptying the 
jars and running the eggs through a fine screen, and then returning them to the jars. 
Some fish-culturists are of the opinion that strong light is injurious to the eggs, 
and that the rays of the sun should be carefully excluded from the room in which they 
are undergoing incubation. The incubation period covers about 19 days in a mean 
water temperature of 42.5° F. The newly hatched fry are so very small and delicate 
that the bottom and sides of the receiving tank are lined with a sack of bleached white 
bunting, so shaped as to conform to the outlines of the tank. This not only con- 
stitutes a suitable and convenient container for the fish, but is useful for conserving 
any eggs that may pass from the overflow into the tank. The fry are planted in 
the natural spawning grounds in Great Brook within a day or two after hatching. 
An experiment in the propagation of the “large” Green Lake smelt was described 
by Supt. E. E. Race in a letter dated March 27, 1909. A few of the females and 
males were stripped simultaneously in a pan, and the eggs were found to be as well 
fertilized as those naturally deposited in the troughs, but they could not be separately 
followed, as it was necessary to hold them with others on the cheesecloth bottoms, 
the wire being too coarse and only two troughs having been fitted with cheesecloth. 
It was found necessary to separate the eggs several times by forcing them through 
fine netting to break up the bunches, but they seemed to do well in hatchery jars. 
Race wrote also that he had experimented with eyed eggs and had found that prior 
to eyeing the more they were handled the better the results. He said that they 
could be taken from the jar at any time before they were eyed and rubbed through 
a fine wire screen with the fingers without injuring any of them. As soon as they 
were eyed they were more sensitive but could be separated from imperfect eggs if 
care was taken to have the screen mesh a little larger than the egg and the stage of 
advancement had not softened the shell too much. 
It appears that at present the Bureau of Fisheries propagates smelts at Green 
Lake only. Something of the extent of the operations may be learned from the fol- 
lowing reported data: In 1923, 4,300,000 eggs of the large smelt were collected. 
The loss in hatching was 20,000 and 4,280,000 fry were planted. Of the small smelt 
42.000. 000 eggs were collected; loss, 1,250,000; shipped 12,750,000; and 28,000 fry 
planted. In 1924, of large smelt, 18,000,000 eggs were collected ; the loss was 700,000; 
8.000. 000 were shipped; and 9,300,000 fry were planted. No small smelts were 
handled. 
ANATOMY OF THE REPRODUCTIVE STRUCTURES 
The gonads or reproductive glands (ovaries and spermaries) of the smelt are 
unsymmetrical organs, one on each side of the abdominal cavity. The organ of the 
left side is very much larger than that of the right, and instead of being approximately 
opposite each other, as in Salmonidse, they are situated one behind the other. The 
left gonad is much the larger in both sexes, the right being quite small and not far 
behind the outlet. Both organs are inconspicuous in an immature smelt, but as the 
season advances they enlarge and some months prior to the breeding season become 
quite conspicuous, so much so that often in the fall of the year the smelts have been 
