73] 



STUDY OF SOUTHERN WISCONSIN FISHES— CAHN 



73 



Table 13 



MEASUREMENTS OF LABIDESTHES SICCULUS FROM LAKE 

 OCONOMOWOC FROM JUNE, 1922, TO JULY, 1923 



* Numbers too small to be significant. 



adult. This point will be discussed in detail under the heading of food 

 habits. The change from the position over deep water to the shallow water 

 habitat will be considered at once. 



MIGRATION OF THE IMMATURE FISH 



I have repeatedly stated that after hatching the young leave the shallow 

 water and travel toward the deep. During the first month or six weeks 

 after hatching the silversides is to be found only over the deep waters of 

 Oconomowoc lake and other bodies of water investigated (La Belle, 

 Fowler, Golden, Silver, Upper and Lower Nashotahs and Nemahbins, 

 Okauchee and Pine lakes). Occasionally a school will be located well over 

 the edge of the sand bars in water from three to five meters deep, but far 

 outnumbering these are the schools found over the water of a depth of 

 from 10 to 20 meters. During July, 1923, the writer located 460 schools of 

 silversides in Oconomowoc lake, and measured the depth of the water at 



