u. s. 



Doc. 938. 



Fig. .5.— Scale of ripe female Lrptinis linini'h, :-!.4 cm. Iniii;. taken August 3, 1921, from reservoir of U. S. 

 Fisheries Biological Station, Fairport, Iowa. Very large first-year growth is indicated by position of 

 single annulus a. Smaller second-year growth is duo doubtless to Increased nutritional rcqhircments of 

 developing sexual organs. Scale indicates that the fish from which it came was born early in the breed- 

 ing season. X 2.5. 



Fig. 6. — Scale of female Lep niiis hiinii'is, 3.6 cm. long, which had carried no ri|)e or rii)ening eggs. Fish 

 taken Septembers, 1921, from reservoir of U. S. Fisheries Biological Station, Fairport, Iowa. The fish 

 would have spawned in the next spring at the beginning of the third growth year. Relatively small 

 amoimt of first-year growth and the larger second-year growth, suggested by the position of the annulus 

 a. indicate that the fish from which the scale was taken was born rat her late in the spawning season. X 2."). 



Fig. 7.— Scale of ripe female Lepnmis humUis, 4.0 cm. long, taken .Tune 8, 1921, from reservoir of U. S. 

 Fisheries Biological Station, Fairport, Iowa. The fish from which the scale was taken was in its third 

 year of growth as suggested liy the aimuli n and b, and had not spawned previously. The fish was 

 probably born rather late in the spawning season. This scale, taken in the third year of growth, is corre- 

 lated with that shown in Figure 6, taken in September of the second growth yea'r. X 25. 



