i89i.] THE BRITISH NATURALIST. 7 



assume only one) has sent him forms that might be called by either 

 name, strigilis a.ndfasciuncula, widely distributed and common as they 

 are, never (with this one exception) resemble each other at all. Irres- 

 pective of colour, in which they vary greatly, they differ both in size and 

 shape, fascumcula being always smaller, and the forewings being more 

 truncate, it has a decidedly stumpy look. They also assume the per- 

 fect state at different periods, and when on the wing, their flight is so 

 different that could we see them together it were easy to distinguish 

 them. Fasciimcula is the first to appear, being, in a forward season, on 

 the wing at the end of May. It flies before dusk, with a rather quick 

 erratic movement, much like that of the male of Hepialus lupulinus, 

 though scarcely so swift. Later in the evening it may be found 

 abundantly on the flowers Heracleum sphondyliim and other Umbelliferce. 

 Strigilis is quite a month later in appearing, and though Newman says 

 it flies in the day time, I never saw it on the wing till it was quite dusk. 

 It flies with a steadier flight than fasciuncula, the difference being per- 

 haps difficult to describe in words, but very easy to observe. Both 

 come freely to sugar, but fasciuncnla is much less disturbed by the 

 glare of the collector's lantern, or by him picking off the insects he 

 desires. I cannot remember that I ever saw strigilis at Heracleum or 

 kindred flowers. I am of opinion that these differences of size, shape, 

 time of appearance, and habit, are abundantly sufficient to establish 

 their distinctness by the imagines alone. 



I have bred both species, but cannot say I know the larva of 

 either ; but Newman describes that oi strigilis (" British Moths," 308); 

 and Buckler that of fasciuncula (" E.M.M.," XIII., 62). The differ- 

 ences between the two larvae may be summarized as follows : — Strigilis, 

 greyish green, with hve paler stripes, studded with minute warts, each 

 of which emits a short, stiff, black hair. Fasciuncula is of a pale flesh 

 tint, inclining to greyish ochreons, with darker stripes ; on the sides of 

 the second, third, and fourth segments, are rather large, brown, shining 

 spots ; a fine, soft hair proceeds from each. Finally, Newman describes 

 the chrysalis of strigilis as rather slender and reddish ; Buckler that of 

 fasciunciUa as being stout, and of uniform bulk to a little below the wing 

 covers ; colour, mahogany brown. 



To sum up, then, the imagines differ in size, shape, colour, and 

 habit ; the larvae differ in colour, in the stripes being darker or lighter 

 than the ground, in the size and number of the spots, and in the hairs 



