I30 The Classification of Insects 



orange spots. Now and then we may find a specimen 

 showing a reduction in the size of the orange spots, 

 or an edging of white around the central black, spot 

 on the upper side of the forewing. Or a reduction 

 in the black of the eye-spots beneath the wings may 

 be noticed, so that instead of describing them as 

 " black with white rings," it would be more accurate 

 to say " white with black centres." 



Travelling northward, we notice that this butterfly 

 is much scarcer in the English midlands than in the 



south. In 

 many places in 

 the northern 

 counties, how- 

 ever, it again 

 becomes com- 

 mon, but we 

 find that most 

 of the speci- 

 mens here show 

 characters 

 which, in the 

 southern 

 counties, are 

 exhibited only 

 by a few. 

 Above, the 

 orange spots 

 are generally reduced in size or (in the males) almost 

 absent, and the central black spot of the forewings 

 usually has a white ring. The black centres of the 

 eye-spots beneath the wings are small, and sometimes 

 wanting altogether. 



Crossing the border into Scotland, specimens of the 

 insect, as it occurs in southern England, may still be 

 met with in the south-western counties. But north- 



FiG. 82.— "Brown Argus" Bntler^y {Poivomiiiatus 

 asti-archc). a. Southern English (typical) female 

 flying, showing upper side of wings ; b. at rest 

 showing under surface ; c. male of the Scotch and 

 Irish variety artaxerxes, upper side; d. under 

 side. Natural size. 



