EUrLCEINj;. 69 



being arranged in a double marginal series on botli wingp, in some tbere is a third 

 or discal row, but these markings are variously developed, and in many species some 

 or most of them ai'e entirely absent. The head and thorax are white spotted. In 

 the male the posterior margin of the forewing is usually more or less convex, the 

 rounded outline often covering a large portion of the hind wing even when the wings 

 are extended. Males in most sections ivith one, or tivo, impressed streaks or scrnaJ 

 maris — " androconia," as they are now termed — situated between the lower median 

 veinlet and the submedian, clothed with scent-producing scales, which are differently 

 formed from those on the rest of the wing, together with an androconial paler patch, 

 present in some sections on the anterior portion of the upperside of the hind wing 

 and covered by the convex border of the forewing. AVhen first looked at 

 under the ' binocular,' these sexual marks, when present on the upperside of the fore- 

 wing, appear, in all our genera except Danisepa and Salpinx, as an elongated 

 glistening jagged series of reticulations, as if they were formed of dried excretory 

 matter ; but on steady concentration, this illusory effect disappears, and the scales 

 stand out clearly defined, the previous jagged reticulated appearance arising from 

 the membrane beneath showing between the irregular outlines of the layers of scales. 

 Females with the posterior margin of the forewing usually straight, or but very 

 slightly convex towards the base. 



" In some few species," as stated by the authors of Butt, of India, p. 37, " the 

 sexes differ materially in the colour of the hindwing, the males having this wing 

 nearly uniform dark brown, and the females having it streaked with white, but as a 

 rule the differences in colour and markings are slight, and the sexes are only to be 

 distinguished by their structure and outline, and by the presence or absence of the 

 sexual marks on the wings." 



Key to the Indian Genera o/Eopl(eina, hosed on the presence and position of the sexual marl.-. 



A. No sexual marl: or patch of scent-producing scales on forewing, in male. 



a. Exterior margin of forewing even, posterior margin of forewing very convex Menama. 

 h. Exterior margin of forewing uneven, posterior margin of forewing very- 

 convex Tronga. 



B. One sexual mark or patch of scent-producing scales on forewing, in male. 



I. Sexual mark shm't, slender. 



a. Exterior margin of forewing uneven, posterior margin of forewing almost 



straight Crastia. 



6. Exterior margin of forewing uneven, posterior margin of forewing convex Mahintha. 



II. Sexual mark long, uleruler. 



a. Exterior margin of forewing uneven, posterior margin of forewing hroadly 



convex Karadira. 



III. Sexual mark lung, very Invad. 



a. Exterior margin of forewing convex, posterior margin of forewing convex Pexoa.. 



