64 



U.S. NATIONAL AIUSEUM BULLETIN 2 59 



although this graph is based on data gathered from specimens assigned 

 to S. t. potomacus, it can be readily applied to either subspecies. As 

 size increases, length of antenna 2 approaches the length of antenna 1, 

 and in males between 7.00 and 7.50 mm both antennae become about 

 equal in length. Males over 7.50 mm in length, however, typically 



2nd Antenna 



X 

 h- 



o 

 •z 



hi 



111 



h- 



:z 

 < 3 



St Ant enna 



X / X 



5 6 7 8 9 10 11 



STANDARD LENGTH, MM 



12 13 



Figure 14. — Relation of antenna! length to standard length (body length excluding appen- 

 dages) in Stygonedes tenuis potomacus from seeps in Burleith Woods, Washington, D.C. 

 [Antenna 1 (solid circles), antenna 2 (x's). Regression line calculated by the least 

 squares method.] 



