410 BKITISH LEPIDOPTERA. 



quite the posterior margin of mesothorax (This seems to be the general 

 method of dehiscence in all the 5^ Macro-Psychids). ? . The anterior 

 margin of thorax, or more strictly the dorsal head-piece, separates from 

 the head, the thorax splits down dorsally quite into the 1st abdominal 

 segment, the leg- area is stretched out so that comparatively colourless 

 pupal tissue is displayed between the leg-papillae and between these 

 and the wings ; whether this thinner membrane between the legs and 

 wings splits or not, it seems irregular, and it is very usual for it to 

 split on one side and remain intact on the other (Chapman). 



Habits of pupa. — The cases containing the pupae are kept in a 

 window with a southern aspect. Before the sun comes round they are 

 quite immovable, but as the sun reaches them they wriggle up and 

 down the silken tube that protrudes beyond the sticks of which the 

 cases are made, until the yellow-brown pupae appear to be almost 

 bursting out at the end. At the slightest touch they hurriedly wriggle 

 back, and they also do so as soon as the sun is obscured (Cowl). 



Food-plants. — Sallow, willow, birch, whitethorn, Polygonum 

 aviculare (Bacot), Myricagale, Calluna (Burrows), Sarothamniis (Beutti), 

 Alpine strawberry, sloe, bramble, heath (Weir), Erica, Genista sp., 

 Spartium, Vaccinium myrtillus, V. vitis-idaea, Yicia sp., &c. (Hofmann), 

 grasses, heath, furze (Merrin), Prunns spinosa (Bruand). 



Parasites. — Upon opening cases that I had kept all the winter I 

 found many larvae attacked by ichneumons ; the larvae must have been 

 the hosts of the parasites throughout the winter (Weir). 



Habits and Habitat. — The male imagines, at least in confinement, 

 appear to emerge in the early evening from 5 p.m. to 6 p.m., although, 

 occasionally, examples will appear until 8 p.m., and we have once observed 

 a morning emergence (a female). The species, however, appears to be es- 

 sentially an early evening or day-flier, assembling readily to the females, 

 that do not (except by chance or when not fertilised)" leave the case 

 until the eggs are laid, when they drop out and perish. Copulation 

 takes place in the case, the female coming up to the entrance of the 

 extended silken tube from which she repeatedly pushes out the head 

 and anterior segments of the body, and thus makes a means of entrance 

 for the extensile abdomen of the male, which is forced into the tube, 

 for the purpose of copulation, the wings being pressed upwards during 

 actual pairing by the upper edge of the tube. I As soon as copulation 

 has finished, the female wriggles back into the pupa-skin and deposits 

 her eggs therein, finishing in a comparatively short time. She then 

 usually falls from the case and dies. Cowl notes that he believes that, 

 just before doing so "she spins the wool plug that fills up the emergence- 

 end of the tube and that this serves as a protection for the eggs." If she 

 remain unfertilised, she will, in time, wriggle out of the case, without 

 laying her eggs, fall to the ground, and by means of powerful vermiform 

 movements, cover a considerable distance, and will live some days in 

 this exposed condition. The female is thus very active (within limits) 

 and muscular considering that she appears to be chiefly formed as an 



* Barrett's statement that the " ? leaves the case " (Brit. Lep., ii., p. 334), and 

 McEae's that " the female on emergence falls to the ground" are quite incorrect as 

 to the normal habit, except within the limits suggested above. 



f Stevens and others have stated that the ¥ turns round in the case so that the 

 male can pair with her, this is not so, she wriggles to the top of the tube and keeps 

 her head at the open end of the case. 



