20 



THE YOUNG NATURALIST. January 



bearing out Mr. Stainton's original time of appearance ("Entomolo- 

 gist's Monthly Magazine" vol. XXIII. , p. 163). Mr. Sang also agrees 

 with Mr. Stainton's statement, mentioned above, and refers to it, 'Ent. 

 Mo. Mag.' vol. XVIII., p. 144. 



Larva- — With regard to the very early life of this larva, Mr. Sang 

 writes: — " One egg will probably be laid in each flower, and the larva 

 must emerge soon after (as the plant dies down in winter), and mine 

 down the stem into the root, where it remains until the fresh shoots are 

 thrown up in the following spring, up which it works as the plant grows » 

 throwing out frass from the joints, and causing the whole plant 

 to droop, very like the effects produced by the larva of Exaretia allisella 

 in the stems of Artemisia vulgaris, and becoming full-fed about the end 

 of June," ("Entomologist's Monthly Magazine" vol. XVIII., p. 144). 

 A very full description of the larva from the pen of the late Mr. Buckler 

 occurs in the "Entomologist's Monthly Magazine" vol. XII., p.p. 233- 

 234, where he writes : — "On June 8th, 1875, Mr. John Sang of Darling, 

 ton, very kindly sent me several larvae of this species, in various stages 

 of growth mining within stems of Tanacetum vulgare. As soon as their 

 food began to wither, fresh sprays of tansy were provided for the larva?, 

 which, often as this occurred, readily left the old stems to commence 

 mining into the fresh ones. The mouth of the mine is generally be- 

 tween the axil of a leaf and the stem, with a few silk threads spun from 

 one to the other, just above it, among which the dark olive or blackish 

 frass becomes entangled, as the larva pushes it out from time to time 

 in its course, head downward ; the quantity there increases more and 

 more, until the accumulation becomes very conspicuous, and betrays 

 the presence of the larva." 



While immature, the larva is darker in its colouring than it after- 

 wards becomes ; it is blackish-green when not more than a quarter of 

 an inch long, glaucous-green with grey stripes when about three- 

 eigths in length; but, when full-grown the larva measures a little 

 more than half an inch, its figure moderately slender, cylindrical, and 

 tapering a little from the third segment to the head, which is rather 

 rounded ; it tapers also from the eleventh segment to the end of the 

 thirteenth ; the segmental divisions are well defined on the back, and 

 rather deeper on the belly ; the legs all tolerably well developed. 



The colour of the head is very pale, either of a brownish-yellow or 

 greyish-yellow, semi-pellucid and shining, the ocelli large and blackish, 

 the mouth blackish-brown ; on the second segment, is a shining plate 



