192 [August, 1894. 



less thickly dusted with fuscous, but in the London and Thames-mouth districts it 

 is very dark, owing to the presence of numerous blackish scales. It is, therefore, so 

 much deeper in colour than obsoletella, which is usually pale greyish-stramineous, 

 sparingly peppered with fuscous, that only in aberrant individuals do these species 

 resemble one another, After examining large numbers of both, I think that, in 

 separating them, more reliance should be placed on colour than on size or markings ; 

 they vary in size, and in both insects the black dot-like spots are similarly situated, 

 and liable to be elongated into short streaks, while the pale hind fascia is often 

 wanting. 



7. L. obsoletella, which otherwise differs from the first five species in the same 

 points as the preceding, is best distinguished from it by its much paler ground-colour. 

 Fischer von Roslerstamm says that obsoletella, when in good condition, is " never so 

 darkly coloured " as atriplicella, and that even worn specimens of the latter are 

 " sufficiently distinguished " from the former by the presence of two blackish streaks 

 on the under-side of the abdomen. But since he had only met with atriplicella in 

 Vienna, and his type is the dark form, he probably did not know the paler forms, of 

 which some examples show on the under-side of the abdomen no trace of any darker 

 streaks, whereas, in obsoletella, on the other hand, the same part, as allowed by 

 Fischer himself, " occasionally shows traces of two grey longitudinal lines." 



The life-histories of both atriplicella and obsoletella, and the entirely different 

 modes of life by which the larvse betray their identity even when feeding on the 

 same plant, as well as the larvge, pupae and imagines, have been fully described 

 by Fischer, who also gives admirable figures (with magnified parts, &c.) of them in 

 those stages [atriplicella (dark form), p. 223, pi. 78 (1839) ; obsoletella, p. 225, pi. 

 79 (1840)]. As no English descriptions of the larvae or pupae appear to have been 

 published, the following translations by myself of those ui Fischer's work may 

 perhaps be useful : — 



Larva and pupa of Lita atriplicella, F. v. E. 



Larva. "It has sixteen legs, it is greenish-yellow, sometimes even grass-green, 

 with a dark — sometimes even only a light — rose-red suffusion on the back, and black 

 shining warts, each of which emits a hair. The head is honey-yellow with four 

 brown side spots (J. e., two on each side — E. R. B.), the prothoracic plate green, 

 with a few brown dots on the sides, and on the green anal extremity ten small black 

 warts are visible. The legs are pale green, the points of the claws blackish-brown." 



[In the first sentence there is, in the original, no "," after " grass -green," and 

 no " — " between "light" and " rose-red," but to avoid ambiguity, I have ventured 

 to insert them, because, from Fischer's language, apart from very strong corrobora- 

 tive evidence, I myself entertain no doubt as to his exact meaning. — E. R. B.]. 



" The pupa is brownish-yellow, it has paler wing-cases and, when the imago is 

 well formed, dark red shining eyes ; the anal extremity is armed with hooked 

 bristles." 



The larva, which " is very active and drops to the ground at a very slight 

 touch " (F. V. R.), lives in a silken gallery among, and feeds on, the young leaves, 

 flowers, or seeds of its food-plants, and I have little doubt that the eggs are laid in 

 the shoots, flowers, or young seeds, according to the time of year. Mr. Fletcher found 

 that larvae from Southend, which produced the dark form of the moth, although very 



