424 BRITISH LEPIDOPTEKA. 



The most extreme form of blotching is observed in A. erythrus and 

 certain forms of A. purpuralis (minos), in which the whole of the central 

 area of the wing is entirely red. Standfuss says that individual examples 

 of A. achilleae, A. brizae, A. viciae, A. trifolii and A. lonicerae present 

 aberrations occasionally almost entirely red in colour. The next step is 

 that in which the red is broken up into three wedge-shaped blotches, as in 

 typical A. purjyuralis and A. punctual, the formation of these exhibiting the 

 origin of the spotted forms. In the least strongly blotched species of this 

 group, e.g., A. scabiome and A. brizae, these wedge-shaped blotches are 

 reduced to lines, and often give a distinct idea of two basal, two central, 

 and an apical spot being united (the upper central to the apical, and the 

 lower central to the lower basal). Coming to the five-spotted forms, we 

 find certain species with the apical spot not particularly large, but oval, as 

 in A. Lavandulae, A. lonicerae, A. trifolii, A. viciae (meliloti) and A. exulans, 

 whilst a second group, represented by A. achilleae, has the apical spot 

 very large, suggesting a double-spotted origin (or a tendency to cover 

 the area occupied by the two outer spots in the next group). The six- 

 spotted group is interesting — A. hippocrepidis, Stphs., and A. ochsen- 

 heimeri (from the Alps), having the sixth spot ill-developed in the male 

 (sometimes only visible beneath), but well-developed in the female, 

 whilst A. filipendulae, A. transalpina, etc., have the six spots well 

 developed in both sexes. It must be from near the first of these latter 

 groups that^4. peucedani obtained its variable spotting. The ochseiiheimeri 

 group leads naturally up to the five-spotted forms — A . trifolii, A. lonicerae, 

 A. viciae (meliloti), A. exulans, etc. The last group to be considered has 

 five red spots and an outer transverse lunular mark, and is very near 

 the five-spotted species, in spite of the remarkable creamy rings that 

 surround the red spots of such species as A. camiolica, A. occitanica and 

 A.fausta, for in A. camiolica ab. berolinensis the creamy rings have not 

 yet appeared (or have been suppressed) , and in some extreme forms of 

 this aberration the outer transverse band is reduced to a mere red scale 

 or two, and is occasionally absent altogether. In this state, it is difficult 

 to separate from a small A. trifolii. The blotched aberrations of the 

 species of this group, too, form their blotches as in confluent A. 

 trifolii, and not as in A. purpuralis (minos), that is, they unite in 

 adjacent pairs — basal with basal, central with central — and then by 

 transverse lines uniting them more or less centrally, and thus do not form 

 three wedge-shaped spots, but a real blotch. A. exulans and A. viciae 

 (meliloti) blotch rarely, but when they do, the tendency is to follow 

 A. purpuralis {minos). 



In speaking of these spots in detail, it is well to have some sort of 

 nomenclature. For this purpose, we use the numbers 1, 2, 3, 4, 5, 6. 



1 is the upper and 2 the lower of the basal spots ; 3 and 4 are the 

 upper and lower of the middle pair respectively ; 5 and 6 the upper 

 and lower of the outside pair. In the type of A. purpuralis, 1 is con- 

 tinued along the basal half of the costa, forming a wedge-shaped spot ; 



2 is joined with 4 into a second blotch, whilst 3 is joined to 5 (and 

 somewhat enlarged towards 6) to form a third blotch. The three 

 being generally separated by the green nervures that fall between them. 

 In the ab. pluto, the extension of the blotch 3 + 5 is not enlarged 

 towards 6, but is cut off sharply on the outer edge of 5 ; whilst in the 

 ab. polygcdae, the blotches characteristic of the typical form are not 

 separated by the darker nervures, but occupy the greater part of the 



