288 PROCEEDINGS OF SECTION D. 



Great care was exercised throughout the whole operations, and no 

 one was allowed to so much as touch a fish with the hands. The mode 

 of keeping the fish while in captivity in the Nepean was also largely 

 responsible for the success. There have not been wanting in the past 

 years many who, whenever the question of the transportation of the 

 Australian bass into western waters was put forward, urged that it 

 would be very difficult, and that at least great loss would be 

 experienced. Such has not been our experience, because common sense 

 methods have been used. 



Though we will, naturally, not look for big results for some time, 

 there appears to be every reason to consider that the bass will prosper 

 in their new home, notwithstanding the many and diverse enemies 

 which they — as in their present natural habitat — will have to contend 

 with. It is hoped that further consignments Avill be placed in other 

 portions of the Cudgegong and other Macquarie River feeders, as well 

 as some of the majiy other suitable western waters at an early date. 



As in the case of the Bell River, it was considered advisable to 

 close a small portion of the river here to fishing to give the fishes a 

 better chance of survivintj. 



5.— A SIMPLE DEVICE FOR IMPROVING THE WATER 

 CIRCULATION IN FISH PONDS. 



By David G. Stead, F.L.S.. Superintendtnt of Fishery Investigation, Nep} 

 South Wales State Fisheries Department. 



In constructing rearing or retainiiig ponds for trout or other 

 fresh- water fishes, in which it is intended to keep up a regular running 

 supply of wr.ter, it is desirable to so arrange intake and outflow and 

 the shape of sides and bottom as vv^ill ensure a perfect water circulation, 

 so that the fullest advantage ma,y be obtained from whatever supply 

 is available^more particularly where the supply is limited. There 

 should be no " pockets " nor underlying body of still water, and the 

 shape of the ponds should be such as to do away with all corners. By 

 following this plan, the water entering by the intake will spread out 

 throughout the entire pond, and will leave again carrying with iti a 

 great deal of the fine floccTilent matter which otherwise would be 

 constantly settling and giving trouble. 



In very many ponds for trout and other fishes — I am thinking here 

 principally of the former — the arrangemejit is not as above outlined, 

 but is as follows : — The water enters in a iiarrow and shallow and 

 perhaps somewhat meagre stream at the surface of the pond, and lea\ie8 

 again still at the surface. That means there is a " skin " or upper 

 layer only of freshly aerated water, flovv'ing over the pond ; and a big 

 body of more or less foul, dead water, underlying it. This makes at 



