A CRITICAL STUDY OF AMOEPHA POPULI, LINN. 63 



pale rusty basal spot of the hindwings, and this is also the case 

 with Holle's variety. Holle's embarassment, enhanced by Esper's 

 description, seems to me to be the reason of the creation of the var. nalicis 

 or palustnn, although Holle had not the extreme aberration subjiava. 

 If there really is an obsolete aberration palustris on the mosses of 

 Hamburg (near Eppendorf, Borstel, Niendorf, Oher moss, etc.), as 

 described by Holle, we have a form even surpassing ab. subjiava. But 

 I can assert Avith great probability, and the EntoivoloyiHche Verein zu 

 Hamburg is of the same opinion, that the ab. paluxtria has never been 

 found there yet, and it is not likely to be found, because there does 

 not exist a yellow A. populi without the red basal blotch of the hind- 

 wings. Therefore Holle's ab. palustris is, in my opinion, imaginary, 

 and the name invalid. Dr. Speiser, giving Holle's ab. palustris the red 

 basal spot of the hindwings, that is to say, by changing the diagnosis, 

 brings about an identification between ab. 2jaZ;t.sf7-/.s' and ab. pallida, 

 but this cannot be allowed, although I claim to have shown already 

 that Holle has made a mistake in diagnosing Esper's as well as his 

 own variety. I therefore must for the present retain my variation 

 scheme of A. populi, the 2nd and 3rd groups of which are defined as 

 follows : — 



II. Group. — Hereto belong the lighter grey or ash-grey coloured 



specimens, the median and marginal area of which often appear 

 of a bronze-brown, rusty-brown, or olive colour — Forma cinerea. 

 (fl) Transverse lines strongly developed ; rust blotch of the 

 hindwings very distinct =i)opuli, Linn., 1758. 



(b) Transverse lines indistinct or weak ; rust blotch mostly 



paler = ab. cinerea- diluta, Gillmer, 1904 (var. tremnlae, 

 Glaser, 1863 pro parte; ab. borkhauseni, Bartel, 1900 

 pro parte). 



(c) Without transverse lines, all areas of one colour ; rust- 



coloured blotch weak = ab. tremulae, Borkh., 1793 (var. 

 populi, Esper, 1781). 



III. Group. — White-grey, pale; median and marginal area often mixed 



with a rusty-yellow colour — Forma pallida. 



(fl) As sub 11(7 = ab. pallida-fasciata, Gillmer, 1904. 



(b) As sub 116 = ab. pallida, Tutt, 1902 (ab. tremulae, Glaser, 



1853, 1854). 

 (o) As sub IIc = ab. sub/lava, Gillmer, 1902. 



Explanation of Plate III. 



[Fig. 1. — Amorpha populi, Linn., ab. tremulae, Borkh., 1793 (coloured figure), is 

 omitted.] 



Fig. 2. — Amorpha populi, Linn., ab. tremulae, Borkh., 1793. — Photo of Koch's 

 specimen taken in February, 1901. This specimen is kept in the 

 collection of the Zoological Gardens in Frankfurt-a.-M., sub no. 10125. 

 Natural size. 



Fig. 3. — Amorpha populi, Linn., ab. pallida, Tutt, 1902. — The most extreme 

 specimen of A. populi of Holle's collection, which Holle is supposed to 

 have named salicis or palustris, and described it erroneously as being 

 without markings (transverse lines), and without any red basal blotch 

 of the hindwings. One-and-a-half times natural size. 



