AMORFHA POPULI. 471 



Herr Binzer succeeded in finding a larva on aspen from which a 

 variety appeared, agreeing most exactly with Borkhausen's 

 description. In order that others may be able to convince them- 

 selves of the correctness of these statements, Koch adds to his work, 

 on pi. i, fig. i an accurate figure, copied from nature, and concludes : 

 " It only remains to be remarked that this variety does not result from 

 all larvae of populi which live on aspen ; for those which I have not 

 rarely found thereon have all produced typical populi" Glaser 

 describes it ( Der Neue Borkhausen, p. 83) as : " The small light aber- 

 ration of the poplar-hawk, of greenish-whitish ground-colour and with 

 weaker markings, usually also with the rust-coloured spot almost 

 obsolete, which is found in certain districts, e.g., about Biedenkopf (on 

 the Upper Lahn), on aspen in woods, and having a very pale-green, 

 sometimes blood-red spotted, larva. This aberration was known 

 already to Esper and Borkhausen as the aspen-hawk, which they 

 treated as a separate species." He also repeats Koch's 

 statement that " Zetterstedt's Smer. tremulae is, however, a quite 

 different species from this aberration. One also very often finds 

 larvae of the ordinary poplar-hawk on aspen, and a noteworthy 

 variety is only produced by a long succession of generations 

 on aspen. In Heydenreich's Catalogue, var. tremulae is omitted, 

 but Meigen has described it correctly, others only from hearsay." 

 Bartel observes : " $ . A small and light form A. populi, with 

 greenish-grey ground-colour, weaker markings and almost obsolete 

 rust-red basal spot of hindwings. This aberration, in which Caradja 

 (Iris, ix., p. 3) suspects a transition to the true A. tremulae, has 

 no connection with this eastern species, and is only a casual 

 aberration of the very variable A. populi. Hesse — about Biedenkopf 

 on the Upper Lahn, Giessen ; Belgium ; Roumania — in the forest of 

 Grumazesti, &c. Middle to end of June." 



y. ab. rufescens, Selys, "Ann. Soc. Ent. Beige," i., p. 42 (1857); Bartel, 

 " Palaeark. Gross-Schmett.," ii., p. 193 (1900). — Rufescens a fond roussatre pale, 

 ressemblant un peu au S. quercics du midi. Belgium (Selys) ; Douai, rare (Foucart). 



d. ab. fuchsi, Bartel, "Palaeark. "Gross-Schmett.," ii., p. 193 (1900). 

 Rufescens, Fuchs, "Jahrb. Nass. Ver. Nat.," xlii., p. 204 (1889); Kirby, "Cat.," 

 p. 710 (1892). — In this aberration the grey of the ordinary form is replaced by a 

 delicate fox-red, which results in making the specimen widely different in appearance 

 from other A. populi. The parts of the wings which have the fox-red colour are 

 the central and marginal areas of the forewings and the margin near the apex of 

 the hindwings. The base of the hind wing is dull rust-brownish, not dark red-brown 

 as in other A. populi. The rest of the wings is almost rose-coloured in aspect, much 

 more delicately coloured than ordinary specimens, viz., the basal area of 

 the forewings, the space between the central and marginal areas of the forewings 

 where the fox-red colour shades off on each side into the rose-colour without 

 distinct demarcation ; lastly, a marginal spot above the hind angle of the forewing ; 

 on the hindwing the area between the dull rust-brownish base and the fox-reddish 

 apex. This central area is traversed on the hindwings by an indistinct double stripe 

 of fox-reddish colour. All markings fainter, much less distinct than in the ordinary 

 form. On the underside also all the wings show more faintly a reddish tone. 

 Through this mixture of fox-red and rose-colour this specimen presents a character- 

 istic appearance. Bred from larva found on Popidus tremula in the autumn ol 1886 ; 

 the imago emerged June 4th, 1887. I have received another ? from northern 

 Germany, which entirely agrees with this in colour and only differs in its better 

 expressed markings (Fuchs). 



Bartel renamed Fuchs' ab. rufescens as not agreeing with Selys 

 aberration of the same name, and writes as follows : " ? s. 

 All the markings weakened, and much more indistinct than in the 



