THE EARLIER STAGES OF COLIAS HECLA. 83 



C. hecla described by Staudinger, during my stay there in 1912, 

 and the only leguminous plant I could find in the district was 

 the Astragalus alpinus of Linn6, which the ' Index Kewensis ' 

 states is the Phaca astragalina of De CandoUe, and which grew 

 freely, locally. 



Later on, at Laxelv, in the Porsanger Fjord, as noted in 

 * Entomologist,' xlv. p. 339, I found C. hecla in great numbers, 

 flying over flat rough meadows and fields in which A. alpinus 

 grew abundantly ; this plant is undoubtedly its food-plant there, 

 and almost certainly, for the above reasons, at Bossekop also. 



I do not, of course, know in how many localities in Lapland 

 — a great part of which is entirely unexplored — C. hecla is found, 

 and if it is always associated with A. alpinus, but it is certainly 

 a very local species, found only in the above-mentioned localities 

 of those I have explored, although it is stated to occur also on the 

 north side of the Tornea Traske in Swedish Lapland. In all of 

 these localities A. alpinus is an abundant plant; but it is so 

 local that I do not recollect ever seeing a specimen elsewhere, 

 though I have explored a great many miles of suitable country 

 in Arctic Scandinavia. 



The only other leguminous plant I could find in the Por- 

 sanger Fjord was what I think was a species of Vicia, which in 

 the latter part of July had beautiful trusses of mauve flowers, 

 and which grew about one foot high, and was plentiful along the 

 shores of the Fjord at Kistrand. This plant the larvge of 

 C. hecla refused to feed upon. They also refused white and red 

 clover, which I offered to them on my journey home, and which 

 grew freely at Tromso and at various places touched at south of 

 that town. 



It seems probable that the larvae of the two exclusively Arctic 

 species of Colias occurring in Europe — C. hecla and C. luerdandi 

 — feed exclusively in nature on A. alpinus. It should, however, 

 be noted that C. hecla does not occur on the south side of the 

 Tornea Traske, where A. alpinus is an abundant plant, and 

 where C. iverdandi flies in great numbers. 



The ova of C. hecla were to be found plentifully at Laxelv at 

 the time of my visit, July 11th to July 16th, 1912, almost every 

 individual food -plant examined having some attached to it ; they 

 are deposited singly. 



The ova is of the usual Colias type, upright, the vertical 

 and horizontal diameters are 1*25 mm. and 0*65 mm. respec- 

 tively. It has vertical ribs, about twenty-six in number ; the 

 distance they are apart is "05 mm. ; numerous very shallow 

 transverse ribs connect the vertical ribs. The diameter of the 

 apex of the ova is '15 mm. The micropylar area consists of a 

 number of shallow cells; it is not noticeably depressed. The 

 surface of the ova is shining and opalescent. The larva 

 emerges from the side. 



