PSYCHIDES. 107 



cases of Hyalina vesuMella. As the perfect insects showed themselves 

 at the free end of the cases, he opened the latter to blow the females, 

 and was not a little surprised, when eviscerating a female, to observe 

 a larva come out of its abdomen owing to the pressure. The larva 

 was at once recognised as that of a Hymenopteron. Putting three living 

 females into a small glass he obtained two hymenopterous pupae from 

 them, one of which produced an imago. Still one suspects that the 

 larvae must be more or less well-protected by their cases, for the 

 slightest disturbance will cause those of most of the species to with- 

 draw themselves immediately into the case and close the entrance 

 against intruders. 



Eouast says that whatever may be said to the contrary, the rearing 

 of the higher Psychids from larvae, if a few simple rules be observed, 

 is very easy. The cases should be collected as soon as winter has set 

 in, there being fewer deaths from parasites, and less risk of disturbance 

 and injury than if they are collected when full-fed and already spun- 

 up for pupation. The larvae should be kept in boxes having a covering 

 of wire-gauze of small mesh. At the bottom, a layer of peat earth 

 should be placed, then a layer of moss, in order to preserve fresh the 

 plants placed therein. An abundant supply of fresh food is absolutely 

 necessary until the case is fixed, but as several species are polyphagous 

 and content with Poa annua and other low-growing plants, these can 

 easily be planted in the peat and watered occasionally. The boxes 

 should always be kept in the open air and with an eastern aspect. The 

 sun's rays are never too ardent for the larvae, and sun is absolutely 

 necessary for both larvae and pupae. Once also the cases are fixed for 

 pupation they should never be disturbed, because the larvae, having 

 once turned round in their cases for pupation, the attempt to re-turn in 

 order to spin clown the case a second time often proves fatal. It is 

 also important to keep a keen watch at the hour of emergence owing 

 to the rapidity with which the males destroy themselves when kept within 

 a limited space. The moths usually appear from 8 a.m. -10 a.m., a 

 few species later, whilst Apterona crenulella (Iidi,r)is said to emerge only 

 at dusk. Certainly Pachythelia villosella emerges most regularly about 

 6 p.m. and Fumea roboricolella almost as regularly between 2 p.m. and 

 4 p.m. Possibly there is much individual variation in this respect. 



The larvae of those Psychid families that live on the lichens of trees 

 and Avails — Narycia monilifera (melanella) ,Litffia lapidella, Bacotia septum, 

 <fcc, pupate on their feeding-places, but those that are ground-feeders, 

 or that live principally on low plants, grasses, &c, rarely pupate on 

 their food-plants but seek a solid body, large stone, rock, &c, or climb 

 a tree or bush to which they fasten their cases before pupation. 



The cases made by Psychid larvae vary in shape, but each species 

 forms a case peculiar to itself (although some modification may take 

 place if the ordinary materials be not obtainable). Spun by the larvae 

 with grey or white silk, the cases of the lower Psychids are usually 

 covered externally with particles of stone or lichen, whilst those of the 

 higher Psychids are clothed with straws, stems, or even little twigs, 

 arranged in a variety of ways — longitudinally, transversely, imbricated, 

 or irregularly. But even among the higher Psychids, the mode of 

 covering adopted by the more generalised families is often maintained, 

 and we find some Avith cases clothed Avith particles of rock, others Avith 

 lichen, or fragments of bark, moss, dead leaves, or herbaceous plants. 



