18B8.] 251 



position of the first line. I will now say a word about the costal 

 lappets, flaps o£ membrane, folded back beneath the fore-wings, and 

 clothed with highly specialized scales. The first point to be noticed 

 is their large size in our insect, as compared with elutella. Examined 

 with a pocket lens the body of the flap in elutella is seen to be 

 covered with large coarse scales, whilst along its free border is a curled 

 fringe of moderately long hair-like scales. In semirufa, the coarse 

 scales are apparently absent, and the whole surface is thickly covered 

 with long, straight, hair-scales, to the great length and number of 

 which the lappet owes its size. Pursuing the subject further, with 

 a sharp lancet I removed a lappet bodily from each insect, and placed 

 them under a microscope. I found that the coarse scales in elutella 

 are clavate, and darkly granular from the presence of pigment ; and 

 that similar scales, though less numerous, are really present in se^ni- 

 rufa, but are hidden by the hair-scales. The latter bodies, however, 

 are unmistakeably different in the two insects. In both they may be 

 described as spear-shaped, and provided at the end with a minute 

 projecting point ; but in elutella they are little more than half as long 

 as in seonirufa, and are at the same time nearly half as broad again, 

 thus reversing the proportions ; their shafts are also curved, which 

 explains the curl in the fringe already mentioned, and they have 

 lancet-shaped ends, whereas in semirufa they are blunt-ended. I have 

 entered thus minutely into the subjects of the lappets, because, as 

 they are what we call secondary sexual characters, it seems to me that 

 the differences in their structure are of great importance, and ought 

 to count a long way in settling the question of species, even if they 

 do not absolutely decide it. 



The larva is cylindrical, of moderate proportions, tapering but slightly at either 

 extremity. White, tinged on the upper surface with pale smoky. Head pale brown 

 or amber. Thoracic plate black, divided by a pale line. Anal plate also black. 

 Spots black, small, but distinct ; the trapezoidals arranged almost in a straight line, 

 one behind the other. 



There yet remains one point deserving, perhaps, a few remarks. 

 Although my larvae took very kindly to their nuts, it is not to be 

 supposed that they feed upon them in a wild state, but, probably, like 

 many of their congeners, they have accommodating appetites, and live 

 on almost any kind of material, animal or vegetable, provided onlj it 

 be not living. This being so, it may not have been accidental that it 

 was out of ivy that Dr. Jordan beat his specimens many years ago in 

 Devonshire, or that in my own case the same plant grew close at hand, 

 for these old ivy bushes are stored with refuse materials of many kinds, 



