PSYCHE. 



A COMPARISON OF COLIAS HECLA WITH C. MEADII AND 



C. ELIS. 



BV THOMAS E. BEAN, I.AGGAN, ALBERTA PROVINCE, CANADA. 



[Annual address of tlie retiring president of tlie Cambridge Entomological Club. 8 .March, 189) 



The Males. 



As the males of Meadii ;iru! Ed's are 

 but narrowly separate, I have made a 

 series of measurements from which to 

 derive numerical averages in the two 

 species, as to total expanse of the front 

 pair of wings, as to breadth of dark 

 border of primary at middle of outer 

 margin, and particularly as to the pro- 

 portion between this breadth of dark 

 border and the expanse of the corres- 

 ponding wing. These tests were also 

 applied to Hecla, although there 

 scarcely of equal significance on 

 account of tlie small number of 

 examples at mv command. Mr. David 

 Bruce very kindly sent me a large 

 series of Meadii for examination, so 

 that 1 have been enabled to compare 

 42 cj , 33 9 Meadii with 7 c? ? 5 9 

 Hecla and 56 (J , 75 9 Blis. 'I'hc 

 males were individually measured, and 

 the data reduced to general averages, 

 with following results. 



Average total expanse (sum of the 

 length of the two primaries plus breadth 

 of body) : Afcadii, nearly 47 mm. ; 

 Hecla ^ nearly 45 mm. ; Rlis, nearly 

 50 mm. 



Average breadth of dark border of 

 primary, at middle of outer margin: 

 Meadii^ ^\ mm. ; Hccla, 2f mm. ; 

 Elis^ 3|- mm. 



Proportion between average breadth 

 of d.irk border of primary and average 

 leiigtii of primary (measured from apex 

 to center of base of wing) : in Meadii 

 the breadth of dark border proved to be 

 slightly over 19-^- per cent of length of 

 primary, in Hecla 13 per cent, in Elis 

 slightly over 14 per cent. 



These are significant averages. The 

 individual measurements from which 

 they were obtained show that in regard 

 to expanse of wing, as in other respects, 

 Meadii is in considerable degree less 

 subject to variation than Elis. Meadii, 

 in its extreme terms of expanse, only 

 varies to 4 mm. below its average figure 

 an<l to 3 mm. above its average. Elis 

 ranges to 10 mm. below and to 6 mm. 

 above its own average term. The 

 extremes in Meadii are only 7 mm. 

 apart, but in Hecla they are 10 mm. 

 apart, and Elis has a range of 16 mm. 

 of variation in this dimension, or 

 II mm. if one extremely abnormal 

 example be omitted from the com- 

 parison. The uniformity of expanse in 



