334 LÉPIDOPTÉROLOGIE COMPARÉE 



actual spécimens described. The first three, viz. first, médian and 

 second are dark coloured. For simplicity, I call the white band, 

 preceded and followed by a blackish suffusion, the subterminal 

 line. The hindwings are much the same except that the first line 

 is only exceptionally présent. Both wings hâve a white discal 

 spot, surrounded by a blackish ring, on the transverse vein. Thèse 

 spots may be absent. 



I hâve previously suggested that al pin a and grœcaria should 

 be separated generically from zonana, but I am sure now that 

 the séparation, as far as alpina is concerned, was prématuré. This 

 species I consider to be strictly congeneric with zonaria. There 

 are a few structural points, such as the stronger antennal pecti- 

 nations and the absence of cornuti on the vesica in the genitalia, 

 which might be used to sepatate the two species, italien and grœ- 

 caria from Ithysia, under the generic name Melanocoma but I 

 prefer to call ail four Ithysia. 



The relation between the forms or species h as been very obscure 

 in the past, partly owing to the difficulty of obtaining them, and 

 partly on account of their great variability. I hope that this 

 paper will clear up this confusion. 



I propose to deal with the maies of each species separately, 

 but, for the purpose of comparison I shall discuss the females 

 together. 



Ithysia zonaria * (Schiff.). 



Wing expanse : 30-35 mm. 



This species has caused no confusion as it is so widely distri- 

 buted, being found throughout North and Central Europe and 

 extending even to Armenia. 



The type form, as found in Central Europe, has very dark 

 markings; so dark are they, that they are nearly black. 



* Genitalia figured on PI. B, Fig. 15. 



