191S-] 155 



This is the standard description. Necessary additions have been given in 

 brackets. 



Variation is mainly in the ground colour, which may be pinkish, reddish- 

 ochreous in all shades from pale to dark, or yellow-ochreous ; all more or less 

 tinged with grey. Markings vary but little. The transverse lines are rarely 

 very pale in Britain, but usually of some shade lighter than the ground colour. 

 The sub-terminal dots vary in number from 1 to 5 ; I have only seen one example 

 with all 5 clearly indicated. I have seen one specimen with the white reniform 

 dot obsolete. 



Ab. lineario Gn. — gilvago Hb. 193 = gilvago ? var. Dup., VII, 1, pi. 129, 

 fig. 6, has the fore-wings with the reddish tinge almost entirely replaced by dark 

 grey ; the terminal area is grey and the nervures stand out vei-y prominently. 



Variation. Extreme forms of a deep orange-brown occur on the Continent. 

 I have only seen one British example. In the other direction those with paler 

 grey suffusion mei'ge into forms of typical ocellaris and no hard and fast line 

 can be drawn between the two. 



The figure of Duponchel is a good one. 



*Ab. palleago Hb., fig. 192. "Paler than ocellaris without any tinge of 

 red," is Warren's description in Seitz's " Macrolepidoptera." The figure given is 

 probably copied from Hiibner and shows a whitish insect with indistinct mark- 

 ings. Paler-than-type forms occur here very rarely. They occur more commonly 



* Warren is right in fixing pitlli'dgo Hb. 192, as a lighter-than-type form of ocellaris, but some 

 further consideration of the term as used by earlier British autliors in connection with this 

 species and (lilcmjo is necessary. Barrett (Lep. Brit. Isles," V, p. 378) mentions "the existence 

 abroad of a pale yellow form .... sometimes called ab. palleago," which would appear as it 

 stands to refer to palUayo Hb. 442 ; but if it is read in conjunction with a note by the same hand 

 in the Ent. Mo. Mag. for 1895, p. 94, I think it is prett3' clear that he had in mind some lighter- 

 than-type forna of ocellaris Bkh., and as such it may be allowed to stand. 



The insect treated as a form of gilvago is palleago Hb. 442. Treitsehke gave it specific rank, 

 but Guenee deals with it as a variety of gilvago analogous to the flavcscens form of fulrago L. In 

 the Staudinger and Uebel Catalogue of 1901 it was again given specific rank, which is confirmed 

 by Warren, who gives it a new name, ervthrago. Tutt, in his "Varieties of British Noctuae," 

 follows Guenee, and South, "Moths of the British Isles," II, p. 21, describes the insect and 

 remarks, " this seems to be the pull i ago of fl iibner which has been considered a distinct species ; 

 I think, however, it is only a form of gilvago." The two insects are perfectly distinct, and the 

 use of pinlleago as a varietal name of gilrago should be deleted from Tutt and South ; as both these 

 authors give a description of the insect, none is necessary here, but it may be said that the few 

 specimens I have seen could at once be separated from gilvago by the pale nervures, the pale grey 

 reniform dot and the unicolorous fringes — all characters wliich they share in common with 

 typical ocillarin. Erytkrago does not share the wide distribution of its congeners, and aj^pears to 

 be both local and rare. Frankfort, Budapesth, Italy, and S. France are given as localities. Herr 

 PUngeler's collection, rich in other species, contained only a single example, and his efforts to 

 obtain others for me to work on the genitalia met with no success. Warren's suggestion that the 

 Italian and S. French localities refer i-athor to jMlleago = ocellaris Bkh., looks like another guess, 

 as there ai-e two examples from the last-named locality in the National Collection. A further 

 suggestion that all the poplar feeding gilrago will prove to be (rythrago, supported by the state- 

 ment that " gilvago in Britain Jieds solely on dm," is another haphazard guess which should never 

 have been made. It may not be generally known that gilvago does feed on poplar in Britain, but 

 that it does so in Central Europe is supported by the evidence of recognized authorities in books, 

 by no means difficult of access. 



Fuchs " Stettiner entomologische Zeitung," XLIV., p. 204, states that ho takes gilvago in 

 the noted Poplar Avenue at Hamburg, and Tutt uses this quotation at least twice in his " British 

 Noctuae," IV, V2i, and in the Ent. Record (Vol. VIII). Dr. Wocke states that in Silesia young 

 larvae of gilvago feed on poplar, and Dr. Rossler in " Lejiidoptera of the neighbourhood of 

 Wiesbaden," ISSl, p lo9, writes : "565. G/h'ajro Esp. Larva when young feeds on poplar. " He 

 later remarks that the moth is taken in all its varieties, which he describes, the last being 

 refei-red to palleago Hb. This clearly means that the two insects occur together on jsoplar, and as 

 Wiesbaden is only 20 miles from Frankfort, which seems to be the headquarters of a-ythrago, 

 nothing would be more likely. 



A detailed knowledge of the early stages and an examination of the genitalia are wanted, to 

 fix the position of this species in the genus. 



M2 



