THE PYRAMEID GROUP OF VANESSIDS. 63 



Plate i., fig. 1, represents a very light specimen of F. canliii. In 

 Mr. South's Butter/lies of the British hies, pi. xlv., fig. 4, a dark 

 specimen of P. carditi is figured from an excellent photograph. The 

 lifjht form, induced by heat, occurs wherever the climate is suitable ; 

 the dark foiin, induced by comparative cold, is found fiying in the 

 summer either on high mountains, or, for instance, in Lapland, where 

 its parents are always spring emigrants from the south, and are of 

 the light or intermediate forms. These light and dark specimens 

 seem to represent the limits of the regular facial variation of /-'. cardui 

 under climatic (orseasonal) influence. Someexamples have blue-centred, 

 even-sized, eye-spots (ab. ocellata, Rbl.) on the upperside of the hind- 

 wings (perhaps an atavism), and occasionally extreme symptomatic 

 aberrations, ab. eli/Dii, Rbr., are captured. Distributed over the greater 

 part of the globe, P. cardui occurs from Cape Colony, Australia, and 

 New Zealand in the south, to Lapland and Siberia in the north ; from 

 Spain it ranges eastward through Europe, Asia, Japan, across to the 

 Polynesian Islands and to North and Central America, thence south- 

 wards, erratically, perhaps, even to Cape Horn (compare footnote). 

 Except in Tasmania (Australia) and in the Sandwich Islands, 

 where P. cardui occurs regularly with blue centres to the eye-spots 

 of the hindwings, as hen^hairi, the species does not appear to 

 indulge anywhere in any variation other than that already mentioned. 

 Climatic influence would seem not to afiect this species. Whether 

 captured in the tropics or near the arctic zone, on continents or in 

 islands, on plains or among mountains, P. cardui is nearly always 



venience. I will call the first group of species cardui-loxm and the second atalanta- 

 form. When the distribution of these Pyrameids on the face of the globe is con- 

 sidered, the lact is seen that the cardui-torm species are at home in South and 

 Central America, while those that remind one strongly of P. atalanta, occur in 

 southern and eastern Asia (one species), in Java (one species), Australia (one 

 species), New Zealand (one species), and the Sandwich Islands (one species), and 

 tbat thus the two groups remain neatly separated also by their geographical 

 distribution. In P. carduiand P. atalanta, however, each group owns a migratory 

 form of wonderful flying powers, and these two, especially the cosmopolitan P. cardui, 

 roam almost everywhere, but P. atuhmta, perhaps because a younger, and physic- 

 ally more sensitive, because more highly differentiated, form, has not yet extended 

 its range so far as P. cardui, and especially does notyet occur east and south of the 

 continent of Asia, where four of its nonmigratory relatives flourish. As to the 

 occurrence of P. arrdui in South America, the home of the cardui-iovn\ group, 

 entomological authors seem to contradict each other, one recording the occurrence 

 of P. cardui throughout South America, another allowing P. cardui to roam every- 

 where except in South America, but perhaps P. cardui will be found to have pene- 

 trated down to Cape Horn, and it is possible that only a very erratic occurrence of 

 the species — more uncertain than anywhere else — has given rise to the contra- 

 dictory evidence. Two other species, one again in each group, P. virgiuicusis, 

 Drur. (pi. i., rigs. 3, 7, 11) (cardui-iovm), and P. indica, Herbst (pi. i., flgs. 13, 17) 

 (the nearest relative of P. atalanta, fig. 18), also show migratory tendencies, but 

 in a lesser degree, the first-named ranging from South America across the Isthmus 

 into the United States' territory, the second spreading from its Indian home into 

 Southern Siberia (where it meets with P. atalanta), and eastwards to Japan. In 

 the Canary Islands P. virginieiixis and P. i)idica, the latter as var. rulcanica, Godt. 

 (perhaps both introduced by shipping?) occur together with P. atalanta (and P. 

 cardui?}. It is recorded that rin/f/u'en.s-i'.s has been captured in England twice 

 during the last century, and has been called the " Scarce Painted Lady," but I 

 think one may assume that more specimens than those captured, were introduced 

 accidentally, or had migrated, and that, had the climate been suitable, the species 

 would have stayed, just as it appears to stay in the Canary Islands. 



