S86 BEITISH BUTTERFLIES. 



to be found fullfed in April, when one is searching sorrel roots for 

 Gelechia larvae. At Brighton, Johnson found individuals well fed on 

 March 26th, 1893, but this was a phenomenally early year. Newman 

 states that the summer larvae feed up in about 20 days, and when 

 fullfed rest on the underside of leaves of the foodplant, in a flat 

 position closely appressed to the surface ; if disturbed or annoyed, a 

 larva falls from its foodplant, and assumes a crescentic form, the two 

 extremities approximating, but not meeting ; after a time it resumes 

 its wonted appearance, and glides over the surface of any object on 

 which it may happen to rest, exactly in the manner of a slug, no 

 separate motion of the body or legs being perceptible. Schneider says 

 that, at Tromso, the larvae certainly hybernate at very various ages, and 

 this accounts for the long drawn-out period of night, but Strand speaks 

 •of a certain second brood in the Suldal and various other places in 

 Scandinavia. For the different lengths of larval life in the various 

 broods in North America, see antea, pp. 345-346. Buckler notes that, 

 " when fullfed, and the larva has taken up its position for pupation, 

 it becomes somewhat shorter and thicker, more rounded in outline, 

 the pupal stage being fully assumed after two days." 



Variation of larva. — The larvae when fullgrown present varying 

 forms, but these may all be briefly dealt with. The larva is green, 

 sometimes entirely green, which may vary from pale yellowish -green 

 to dark green, but often with pinkish or purplish dorsal and spiracular 

 stripes ; these may vary from faint and narrow lines to full-coloured 

 and wide lines, extending, in some examples, respectively, downwards 

 and upwards, until in the most extreme cases they meet, and the green 

 is lost in the pinkish or purplish suffusion. Hawes says (Proc. Sth. 

 Lond. Ent. Soc, 1893, p. 140) that the larvae, when large, present 

 varying forms, which may roughly be divided into those that are 

 merely grass-green, and those that have, besides, dorsal and spiracular 

 pink stripes ; these latter are very handsome, and appear to produce a 

 large proportion of $ imagines, although not exclusively confined to 

 that sex. 



Larva. — First instar (newly-hatched) : Ashy-grey, with black 

 head ; a double dorsal crest of dark hairs, half as long again as the 

 larva is thick ; larva about 1mm. long, 0'3mni. wide ; lateral hairs 

 white, shorter, difficult to see ; a very small, square, dark mark for 

 prothoracic plate ; some black dots, but no hairs, between dorsal and 

 marginal hairs; dorsal ridges not sharp (April 26th, 1906). First 

 instar (fullfed) : shows a good deal of colour and marking ; about a 

 third of the way from dorsal to lateral flange is a yellowish line, a band 

 consisting of a yellow stripe on each segment, obliquely upwards and 

 backwards, so that that on one segment starts just below the end of 

 the last one; it is bordered above and below by a narrow red shade ; 

 there is some reddish shading halfway from this to lateral flange, 

 which has a reddish shade above it ; the line of tubercles on dorsal 

 flange has a good deal of reddish ; the lateral flange is not coloured, 

 but agrees with the ground colour, which is of almost a flesh tint 

 rather than a green. The little larva is barely 2mm. long when 

 stretched, and the dorsal hairs of i are about 0-6tnm. long, and 

 bent to about 60° of a circle ; they stand erect, the curve giving 

 a backward sw r eep, with the effect of a fine crest when the larva is 

 viewed sideways ; they are finely spiculated ; those of opposite sides 



