Fearnoiv. — Fish Distribution. 169 



the present time, it is believed that it will be more fully 

 appreciated when further improvements are made in other 

 transportation equipment. 



A system of water circulation which was tried out years 

 ago was a failure for the reason that the water when passing 

 through the pump picked up a small amount of oil which 

 proved inimical to fish life. There was also some difficulty 

 in regulating the overflow or return from the various cans. 

 Since all the water returned to a central tank, one can of 

 diseased fish might infect the entire shipment. The jet 

 aerator, by circulating and aerating the water in each con- 

 tainer overcomes these difficulties. The underlying princi- 

 ple of this aerator may be applied to a device for lifting 

 water or removing sediment from the cans. 



AERATOR FOR MESSENGERS 



Within the last year the dipper which was used for 

 aerating water has been largely replaced by the "Question 

 Mark" aerator, so named on account of the bend in its 

 handle which is made of Vt-inch pipe and serves as an air 

 vent and means for suspending the aerator in a fish can when 

 not in use. The cylinder of the aerator is made of galvan- 

 ized rain spouting and is 41/2-ii^ches in diameter by 6-inches 

 in length. The bottom contains twenty-one circular open- 

 ings which are screened to prevent fish from entering the 

 cylinder. The handle may be unscrewed and the device 

 carried in a small hand bag. 



The device provides quick and efficient aeration, does not 

 injure the fish, can be used to remove sediment or to lower 

 the water in a container, and has a number of other advan- 

 tages over the ordinary dipper. 



The Question Mark aerator has met with geneml ap- 

 proval as it seems to answer the bureau's needs better than 

 any device that has heretofore been used, 



PLANTING FISH 



Closely linked with distribution work is the planting of 

 fish. While much has been written on fish propagation, it 

 seems that comparatively little has been said on fi^h plant- 

 ing. The tendency has apparently been to product fish and 

 trust to Providence to care for them, regardless oi whether 

 planted in unfavorable environment. \ 



Too much care and attention cannot be givm to fish 

 planting, as it is here that all the efforts of the ffeh cultur- 

 ist may be placed in jeopardy. The practice his been to 



