9 



two feet in depth with one free from vegetation and two were 

 from two to six inches in depth, with one also free from vege- 

 tation. These varying conditions represented somewhat the 

 shallow waters of the Islands as regards depth, temperature, 

 presence or absence of vegetation and standing or running 

 water. About equal numbers of the fish were placed in each 

 of the four ponds. 



Fig. 3. — Top-Minnow, Gambusia affinis. Male above, female below. En- 

 larged. (U. S. Fish Commission.) 



The fish thrived in all of the ponds almost equally well, the 

 main advantages of their confinement being the prevention of 

 their being carried out to sea by a freshet and the protection 

 from other predaceous fish. 8 It was determined, however, by 



3 Dr. Tcrdan informed the writer that the Hawaiian fish likely to prey 

 rpcn the tcp-minnows were Sphyracna snodgrassi (Kaku) in the mullet 

 ponds. Elops (Awa-Aua), and Knhlia (Aholehole). 



