ARICIA MEDON. 



233 



tinctness or obsolescence, and these may also occur, though much less 

 frequently, on the forewing as well, on which, however, they are often 

 visible with a lens; occasionally also a slight, but very distinct, outer 

 edging of white may be found beyond these black spots on the hind- 

 wing (ab. albisif/nata, n. ab.). On the underside, in addition to the 

 wide variations of ground-colour already mentioned, the markings 

 also exhibit a very considerable range of difference. The conspicuous 

 light wedge-shaped mark on the hindwing, which is often broad, and 

 in strong contrast with the ground-colour, may be narrowed to a fine 

 line, or even disappear altogether ; the black pupils of the eyespots 

 may be greatly reduced in size (salmacis), or be entirely wanting 

 (artaxerxes) ; the orange appears either in separate, more or less 

 lunular, spots, or the spots may be coalescent, until at. last the effect 

 produced is that of a broad, unbroken band, which looks as if it had 

 been smeared on with a paint-brush. The colour of the orange, also, 

 even without taking into consideration the extreme case of ab. 

 pallidior, varies normally from a deep red-orange to a lightish orange- 

 yellow. Cases of obsolescence of the eye- spots, though scarcer than 

 in many other species of the tribe, are nevertheless sometimes very 

 complete, and in the north of England are far from rare, though few 

 have been reported from other localities ; the partial disappearance of 

 the discal row on the forewings, both at the costa and on the inner 

 margin, is, on the other hand, extremely common. The full row 

 consists of seven spots, that nearest to the inner margin being a 

 double one, this being sometimes divided into two separate spots, 

 would, if the costal spot were present in the same examples, give the 

 appearance of eight separate spots. The costal spot is, however, 

 rarely present, though Hodgson considers that it is commoner than in 

 any other British Plebeiid except P. art/us, and where it is so the 

 double spot has a tendency to complete coalescence, which often takes 

 place even in the absence of the costal spot. The latter, when 

 present at all, sometimes appears on one side only. The geminated 

 spot towards the inner margin is often either single or altogether 

 absent, leaving a row of five spots only ; this may also be the case on 

 one wing only, as may be seen from the following note given by 

 Warren (in litt.) of a series of the 2nd brood, consisting of 16 ^ s 

 and 7 2 s, taken by him at one time on the Chiltern Hills, the costal 

 snot being in all cases absent. 



geminated 



spot 



present, 



5 





j > 



j > 



entirely absent, 



.. 7 





single 



> j 



present, 



.. 3 





double 



15 



on right wing, none on left, 



.. 1 = 



16 c 



geminated 



5 ) 



present, 



.. 1 





5 ) 



) ) 



entirely absent, 



.. 2 





single 



» 1 



present, 



.. 2 





double 



J ) 



on left wing, single on right, . . 



.. 2 = 



7? 





Total 



23 



Reverdin gives (in litt.) a similar note, making a distinction 

 between the specimens from the mountains and the plain, but not 

 between the sexes : — 



