A NEW PRINCIPLE OF AQUICULTURE. 775 



inch mesh, and several thousands of anchovies entered one of the cars in a sin- 

 gle night. Within the cars they lived and grew. Great numbers of very small 

 specimens between 2 and 10 milHmeters in length were taken in July. Mr. 

 Tracy points out a fact of particular significance, namely, that in the tight filter 

 cars many specimens from 2 millimeters to 8 millimeters were found which 

 must have been dipped up by the chain of buckets as eggs or as very small fry, 

 since the fry of 10 millimeters are so quick and wary that they would hardly be 

 caught in this way. There is no doubt whatever that the young anchovies of 

 all sizes thrive perfectly well in the cars provided with screens, and also in the 

 filter cars, and it is more than probable that the eggs of this species frequently 

 hatched in the cars. 



About 20 anchovies placed in one of the filter cars on July 28, 1908, were 

 doing well at the date of writing (September 19, 1908), and showed a very con- 

 siderable growth. 



Hatching and rearing fishes. — Near the end of the season for rearing lobsters, 

 during the latter part of July, when the pressure of other work was relieved, 

 some of the large cars were reserved for definite experiments to test the practi- 

 cability of the method and apparatus as applied to the hatching and rearing of 

 fishes. Unfortunately at this time of the year there were comparatively few 

 fishes whose eggs we could obtain, and we were unable, therefore, to exercise 

 much choice in our material. 



On July 17 a quantity of eggs of the "silverside" (Menidia) were obtained, 

 and, after being fertilized, were put into a car with the filter and bucket-chain 

 rigged as already described. A short-bladed paddle was used like that in figure 

 22. This was hung about 2 feet from the bottom, the lower bearing being 

 dispensed with. 



The egg masses were teased apart into small clusters and placed on a piece 

 of cloth mosquito netting which was tacked to a piece of soaked wood, so as to 

 form a bag, and suspended in the water. The bag thus formed was held extended 

 and kept from collapsing by a coiled piece of insulated electric wire on the 

 inside. (Practically the same method has been used very successfully in the 

 hatching of the flatfish, Pseudopleuronectes .) The eggs hatched in about ten 

 days with apparently no mortality. The young fishes readily escaped through 

 the netting and seemed to thrive perfectly well in the car, where they were kept 

 until August 21, when they were transferred to another similar car, which, 

 however, had a canvas lining. Here they have continued to live until the date 

 of writing (September 19, 1908). There has been no evidence of mortality of 

 any kind during the experiment, although little attention has been given to the 

 feeding, and the fry have had to depend upon the living pelagic food which 

 entered with the water from the chain of buckets. 



