rROCEEDINGS, 1918 17 



LIFE-HISTORY OF PERIGRAPHA PRvESES GRT. 



By Geo. O. Day, F.E.S., Duncan, B.C. 



A female taken at sallows on the flats near Cowichan Bay, in 1916, 

 laid 60 to 70 eggs on the 2nd of April. The eggs were laid somewhat 

 regularly in a patch on the lid of a chip l)o.x attached by the liase and 

 mostly touching each other. The colour was light green and continued 

 the same until the eggs hatched out. Shape, spherical — very slightly 

 flattened at apex and base — the usual striations running from base to 

 micropyle. Hatched 22nd April. Young larvae 3 mm. long. Colour 

 of body a dirty green. Flead very bright brown and wider than body. 

 Roth body and head look spotted with black. O'n the body it is the 

 warts that are black, and on the head, black marks arranged irregularly. 

 The warts extend across each segment but appear irregular — the young 

 larvae would not keep still enough to notice particularly. The larva has 

 four pairs of pro-legs, but uses only two pairs and the anal claspers in 

 walking, which is a decided looping motion. The two pairs of legs are 

 some distance away from the anal claspers. The young larva rests on 

 the two pairs of pro-legs with the rest of the body elevated. Short hairs 

 are emitted from the warts. 



On the 9th of Ma}-, when at the end of the 2nd or 3rd instar, the 

 larvae were abotit eleven millimeters long — most of them of a watery 

 sage-green colour, with five longitudinal white stripes, of which the 

 widest contains the spiracles ; the next widest is the central dorsal line, 

 and the others (narrow-er) between this and the spiracles, but rather 

 nearer the spiracular line than the central line. There are slight black 

 dots across each segment — the four on the dorsal area being situate on 

 the green stripes and the other four on the white spiracular stripes. 

 Head now small and spotted, of a lighter colour than the liody, and with 

 a tinge of light brown. The larvae vary considerably — the greens in the 

 intensity of colour and density of the white stripes. Others have a 

 tendency to be darker in ground colour in the direction of purplish brown. 

 The ventral area is much the same colour as the dark stripes. They seem 

 to prefer spirea to sallow as food, but will eat both. Make use of all 

 their legs at this stage, hut still make a decided loop when walking. 



On the 15th of May, at the end of the third (or fourth) instar, the 

 white stripes are still discernable under a hand lens, but the spiracular 

 lines are the only conspicuous ones. The general colour is a dirty 

 brown, though some larvae are greyer. The dorsal area on each side 

 of the central lines, as far as the two second lines, is lighter in colour 

 than the outer area between the second lines and the light spiracular 

 areas just mentioned. On each segment (dorsal area) are four eye-like 

 marks with a black pupil on the inside, making the eyes look like some- 

 one squinting. The foremost pair are closer together than the hind pair. 

 The conspicuous light spiracular line is rust colour along the middle of it. 



