CELASTRINA ARGIOLUS. 409 



other, burrowing into the body in the same way as they do into a flower (Edwards). 

 Larvae bred on Vaccinium ate away the surface of the leaf while young, and, 

 later, ate the le^f entirely through (Dimmock) ; young larvae on buckthorn ate 

 circular holes •25in. in diameter in the upper surface of the leaves (Scudder). 

 Larva : First instar (newly-hatched): Length '04in. ; head minute, obovoid, black, 

 retractile ; the underside flat, legs retractile, upperside round, the dorsum highest 

 at segment 4, both dorsum and sides slope gradually to 13 ; surface pubescent ; on 

 either side of the mediodorsal line a row of white clubbed hairs, one at the 

 posterior end of each segment ; similar hairs about the base and in front of 2, 

 making a complete fringe around the body ; colour either greenish-white or brownish- 

 yellow (op. cit., pi. iii., fig. b). Duration of stage 4-5 days in spring, 3 in summer. 

 Second instar: Length 0*07in.-0*08in. (after first moult); nearly same shape as 

 before, with pubescent surface, and dorsal and basal hairs ; colour in spring and 

 autumn brownish-yellow ; in summer the same, also greenish- white, and occasionally 

 reddish [op. cit., pi. iii., fig. c). Duration of this stage from 3-5 days. Third instar : 

 Length -12in.--16in. ; general shape as before, but the dorsum now covered from 

 3 to 10 by a low, broad, continuous, tuberculous ridge, cleft to the body at the 

 junction of the segments, the anterior edge of each segment depressed, the sides 

 incurved, 2 is more flattened than before, and the outer border is thickened into a 

 rounded rim. leaving within, the curve, a flat, depressed, space ; surface pubescent; 

 about the base a fringe, as before, and a few short hairs on summit of dorsum ; 

 colour in spring pale green, the dorsum whitish, usually with a median reddish 

 line or stripe from 3 to 10 often macular ; in summer variable, buff or pale green, 

 without spots, the 2nd segment brown ; in some examples, the dorsum and sides 

 are mottled with dark green and brown ; occasionally one is wine-red throughout, 

 or red with a white basal stripe and white along the edges of the dorsal tubercula- 

 tions ; in autumn, dull green, more or less marked brown (op. cit., pi. iii., fig. d). 

 Duration of stage 3 to 4 days. [Fourth instar*: Length, -18in. to -2in.; in shape, 

 nearly as before, the dorsum higher, segment 2 more produced and flattened ; the 

 long hairs on dorsum lost, but the basal fringe as before ; colour variable, as in 

 previous stage (op. cit., pi. iii., figs. e-e A ). Duration of this stage 3 to 4 days.] Fifth 

 instar: Length, directly after moult, -25in.--3in. ; when mature in spring and 

 autumn *4in., in summer *5in.--55in. ;f shape, long, oval, the base flat, dorsum 

 high, and sloping both ways from about the middle, the last segments flattened, 

 the second segment bent forward to the plane of base, produced, flattened, and 

 wholly concealing the head when the larva is at rest ; viewed from above the sides 

 are nearly parallel, the two ends (segments 2 and 13) are about equally rounded, 

 from 3 to 10 inclusive is a dorsal ridge, made of tuberculous processes closely 

 joined at the junctions of the segments, the front edge of each depressed, the 

 posterior edge raised and rounded, so that each process seems to fit into the next 

 preceding ; 2 is depressed in middle, and the whole outer edge is thickened and 

 rounded. Colour in spring: Variable, usually as follows : The ridge whitish, often 

 stained red, or it is brown, light or dark ; the upper part of side olive-green, 

 with a darker green, or sometimes a dull red, patch along the posterior edge of 

 each segment ; below this area pale green, and along base more or less brown ; 11 

 to 13 are mottled in shades of green, often with brown, and 2 is either green or 

 brown ; if the latter, then with a brown patch in the depression ; underside pale 

 blue-green. Colour in summer: Sometimes all yellow-white or all delicate green, 

 2 being brown ; or the ridge is light green and the sides dark, often with brown 

 patches over all ; or light green with a mediodorsal macular deep green band, 

 and a similar one along base; or the whole surface may be wine-red, or even 

 chocolate-brown. Colour in autumn: Green, with more or less brown in irregular 

 patches (op. cit., pi. iii., figs, f-f 6 ); head small, obovoid, dark brown, glossy, placed on 

 the end of a long, conical neck, which can be thrust out to a length equal at least 

 to the breadth of two of the body segments (pi. iii. , figs, i 1 -! 3 ), and, when withdrawn, is, 



* It is highly improbable that this insect has 5 larval instars. One suspects 

 that Edwards' "Fourth instar" is, in reality, the larva well-grown in the "Third," 

 and that his " Fifth instar " is the " Fourth." 



f This bears on our opinion that Edwards' figures of pseudargiolus (pi. ii., 

 figs. 8-9) are summer and not spring forms as he avers. Strangely, his figures 

 (pi. ii., figs. 10-15), noted as the summer form neglecta, are either average or 

 undersized, but as these are produced from the same batches of larvae as the 

 spring emergences, one suspects that there is no very marked difference, but that 

 all the forms vary considerably. 



