LIFE-HISTORY OF THECLA PRUNI. 29 



oblique pale yellow-green stripes and a longitudinal lateral line 

 of the same colour. The ventral surface is whitish green, in- 

 cluding the legs and claspers. The whole surface above the 

 lateral ridge is densely sprinkled with minute amber-brown 

 spines, each with a fluted pedestal base. They are sparsely 

 serrated and sharply pointed and longest on the dorsal area. 

 On the tenth segment is a much longer pair, each in the middle 

 on the dorsal ridge ; these are duplicated on the eleventh 

 segment by a much shorter pair. The spiracles are prominent, 

 of a bright amber-brown. On each segment are a number of 

 tiny greenish glassy discs. The larva in this stage continues 

 feeding almost unceasingly, for several hours' duration I could 

 not detect it stopping. The last stage occupies about ten days. 

 One pupated on June 7th. 



The pupa is short, stout, and humped. It measures f in. 

 long, and ^ in. in diameter from third abdominal segment to 

 the ventral surface. Dorsal view : Head slightly notched in 

 front, angular at base of wings, concave at the waist, swollen at 

 the middle of abdomen, and abruptly attenuated to the anal 

 segment. Lateral view : Head pointed in front ; thorax swollen 

 and rounded, sunken at the waist ; abdomen suddenly rising to 

 third segment, where it is strongly humped, then curves to anal 

 segment ; each segment has a subdorsal point, decreasing in 

 size from the third segment ; between these and the spiracles 

 are two punctures on each segment ; the under surface forms a 

 straight line. Colour : Directly after pupation it is pale greenish, 

 with paler thoracic markings ; it gradually darkens, and in about 

 forty-eight hours assumes its normal colouring, which is as 

 follows. The ground colour of the dorsal surface is a clear 

 brown-black, having a rather varnished appearance, becoming 

 ochreous brown by the spiracles and over the wings ; it is 

 variegated with white on the prothorax ; hind portion of meso- 

 thorax and whole of the metathorax, also each side of the first 

 abdominal segment, and speckled with white on the remaining 

 segments bordering the wings ; the spiracles are prominent, 

 black and shining. The whole of the dorsal surface is sprinkled 

 with tiny amber-coloured hairs. The wings and ventral surface, 

 excepting the abdomen, are smooth. It is attached to the stem 

 of its food-plant by a silken girdle round the waist, and by the 

 cremastral hooks, to a silken pad. In general form, and 

 especially the colouring, it exactly resembles a bird's excrement, 

 which it undoubtedly mimics. 



The pupal state occupies about eighteen days. The one de- 

 scribed emerged on June 25th, which is about the normal time 

 for the appearance of this butterfly. 



It will be noticed that the larva of T. pruni, like others of 

 this genus, moults only three times. I have detected these 

 larvae in the act of devouring each other. In one instance a 



