84 



Fred C. Rohde and Rudolf G. Arndt 



10 



20 



15- 



10- 



5- 



UJ 10 



CO 



i 5 



20 



15 



10 



5- 



T 



ikOa.. 



20 



* 



30 40 



STANDARD LENGTH (mm) 



2,23 MAR. 1975 

 N 65 



30 NOV. 1974 

 N 122 



8 SEPT. 1974 

 N 101 



20 JULY 1974 

 N 94 



17 MAR. 1974 

 N 5 



17 FEB. 1974 

 N 5 



20JAN. 1974 

 N 26 



28 OCT., 4 NOV. 1973 

 N 17 



Fig. 4. Length frequencies of Cottus bairdi from Butler Mill Branch, Sussex 

 County, Delaware, October 1973-March 1975. Solid bars = males; open bars - 

 females; hatched bars = unsexed young. 



