178 [January, 



cise of such a choice seems to fit in better with larval instincts than 

 with those of the perfect state ; and, moreover, there was certainly, in 

 one instance, a marked difference in the sizes of two larvae feeding 

 together. — John H. Wood. 



Tarrington, Ledbury : 



22nd November, 1880. 



On September 23rd, 1S79, Dr. "Wood kindly sent me two larvae of i 

 Pempelia Jiostilis, each between two leaves of JPopulus tremula, spun 

 together with silk, to which quantities of frass were adhering. 



One larva was full grown, the other quite small and preparing to 

 moult, three-eighths of an inch in length and very slender, with 

 blackish head and collar plates, light pinkish-drab body with dorsal 

 stripe just a tint darker, and having on either side of the back two 

 cream-coloured lines, and along the spiracular region two paler cream- 

 coloured stripes, the lowest slanting downwards just at the end of I 

 each segment throughout its course, the ground colour between these 

 and also of the belly paler than that of the back and sides : after 

 moulting on the 26th, it assumed the colour of the full grown example, 

 though it refused to feed, and in course of a day or two a parasitic 

 larva ate its way out, which proved fatal to the unlucky victim, whose 

 shrivelled-up skin alone remained. 



The full grown larva measures nearly three-quarters of an inch 

 in length, of moderate slenderness, the head broad and full, about as 

 wide as the second segment, the body tapering behind from the tenth 

 to the end of the thirteenth, the thoracic segments deeply wrinkled, 

 the others with a deep transverse wrinkle a little beyond the middle, 

 the ventral and anal legs short and much beneath the body ; the 

 rather shining head is blackish-brown, having a broad ochreous stripe 

 on the crown of each lobe and a streak above the mouth, papillae black, 

 finely ringed with white ; the ground colour of the body is a dingy 

 blackish-olivaceous-brown, darkest on the anal flap, rather glistening ; 

 on the second segment, but quite dull on the rest of the body, two 

 fine black lines on the collar change from thence to a plain dorsal 

 stripe, rather darker than the ground colour as far as the last segment, 

 where it is black ; continuous from either lobe of the head is a broad 

 sub-dorsal ochreous stripe on the second segment, opening out beyond 

 in two lines which, after passing the thoracic segments, become more 

 dingy and somewhat greyish-ochreous, and show but faintly ; midway 

 along the side occurs the faintest possible trace of an extra line, thin 

 and indistinct, a sub-spiracular stripe begins on the third segment and 



