236 BEITiSH LEPIDOPTERA. 



Comparison of supposed British Nepticula fragariella with N. 

 dulcella and N. gei. — The few British specimens that we have seen 

 bred from Frayaria venca, and that we take to be N. frayariella, have 

 scarcely exceeded 4 mm. in wing expanse, have distinct reddish- 

 ochreous (almost yellow-ochreous) heads ; the base of the fore-wings 

 brassy-green, the transverse fascia rather silvery than pale golden, the 

 latter running through a purple-brown area that occupies the outer 

 two-thirds of the fore-wings. Wood's X. dulcella are rather less in 

 size, barely 4 mm., the head reddish-ochreous (almost yellow-ochreous) ; 

 the base of the fore-wings brassy, the transverse fascia silvery, but 

 more concave on inner margin, the purple-brown area even more ex- 

 tended than in N. fragariella. The imagines bred from Geum urbanum 

 average 6 mm. The males have, usually, golden-yellow heads and whitish 

 antennal bases, the females deep ferruginous or orange-fuscous heads ; 

 the basal area of the fore- wings is bronzy-purplish (not greenish), the 

 fascia distinctly pale golden, the outer two-thirds bright dark purplish 

 and not purplish-brown, the dark area within the transverse Band 

 narrower. The imagines from Rubus coryiifolius are somewhat similar to 

 those from Geum, but the males have the base of antenna yellowish, the 

 base of the fore-wings bronzy-purple, the transverse band rather 

 broader and more oblique, and the apex brighter and more violet, 

 perhaps blue-black is a better term. 



Egg-laying.— The egg is laid on the upper side of a leaf of 

 Frayaria vesca or Ayrimonia eupatoria, usually by the side of one of 

 the lateral ribs. 



Mine. — The mine is very long and twisted many times. It 

 commences very finely, and then for a considerable distance retains 

 the same width ; it is yellowish-grey in colour, with a darker, central, 

 excremental track. Sometimes, two or three larvae mine in the same 

 leaf, the mines forming a dense tangle (Heyden). Heinemann 

 describes the mine as long, narrow and tortuous, with a rather slender 

 excremental line. According to Eppelsheim, there are considerable 

 differences in the mines of N. fragariella in Frayaria, some showing 

 the characteristic sharply defined frass-line only in the first and last 

 parts of their course, the frass being much more loosely deposited in 

 the middle part. He further notes that the mines in Ayrimonia 

 eupatoria resemble much more closely the mines of N. frayariella in 

 Frayaria, than those of X. yei in Geum, probably because the Ayri- 

 monia is more closely allied to Frayaria than Geum. Our own notes, 

 from a long series of mines kindly sent by Mr. W. H. B. Fletcher, are 

 as follows : The mine is very much finer than that of X yei, shorter, 

 and with more small convolutions. The total length of the longer 

 mines does not exceed three inches, not more than half the length of 

 an average mine of X. yei, and it is not above half the width of the 

 latter, and the blistered appearance of the leaf above a mine of X get 

 is practically absent in the mine of X. frayariella. The frass forms an 

 exceedingly slender continuous thread through the centre of the mine, 

 from its commencement to its end, in some, however, with a slight 

 tendency to the separation of the pellets in the middle part of the mine. 

 This mode of disposal of the frass leaves a very clear margin on either 

 side, causing what appears to be a fine, white, convoluted path on the 

 upper side of a leaf, but quite invisible on the lower side, unless held 

 against the light. In some of the mines, in leaves of Ayrimonia 



