180 BRITISH LEPIDOPTERA. 



of the labrum, two (sometimes one or none) other bristles" above these ; 

 the eyes prominent, the antennae apparently almost free, running along 

 costa of forewings to end of second pair of legs (i.e., almost to apex of 

 wings) ; the third pair of legs (free at tips) project just beyond wings ; 

 the legs with conspicuous little terminal knobs (? claws) ; well-marked 

 scars in position of larval prolegs ; a deeply-marked median furrow 

 extending to the anus, just in front of which are the external sexual 

 marks, which seem to consist only of a slight terminal deepening of 

 the furrow. [Described April 14th, 1899, from a pupa obtained at 

 Wellington College, the imago emerging just as the description was 

 finished.] How completely the ? pupa is a mere egg-bag is well 

 shown by the fact that, in extracting a pupa carefully from its case, a 

 slight pressure on the suture, between the head and anterior border of 

 the prothorax, immediately caused the extrusion of some eight fully- 

 formed eggs through the aperture. It also suggests the delicacy of 

 the pupal cuticle. Bacot notes the pupa as slender, gradually tapering 

 to anus, which is rounded, smooth, and without armature ; pale brown 

 in colour, darker on dorsal area ; the wings distinct, the forewings 

 reaching to end of the 2nd abdominal segment, the hindwings visible 

 above (dorsal) forewings ; spiracles small, raised, and circular, their 

 lining showing through the envelope ; the tubercular setae on iv and 

 v (subspiracular) small but distinct, iv larger than v ; vi also distinct 

 below them ; the seta on iii larger than that on iv ; that on i is very 

 weak, ii larger and longer (i slightly inner to ii), the position of 

 tubercles (and setae) as in larva. (The pupal stage of this individual 

 lasted from April 6th-23rd, 1899.) 



Dehiscence. — The pupal envelope is thrust out at least two-thirds 

 of its length, and the head-, leg-, and antenna-pieces come away like a 

 shield, but are still attached by their lower ventral portions to the rest 

 of the case and hang on as if hinged (Bacot). The eye-covers go with 

 the faceparts and antennae on dehiscence, the first legs (and trochanters) 

 also adhere to headpiece (the legs do not so adhere in N. monilifera) 

 (Chapman) . 



Food-plants. — Lichen candelaris which grows on rocks and old walls 

 (Linne), lichens growing on fences and tree-trunks, also dead moths 

 (Speyer), Agaricus (Hofmann), lichens, dead flies, &c. (Hartmann). 



Parasites. — Campoplex psilopterus, Gr., Hemiteles gastrocoelus, 

 Etzb., Microgaster longicauda, Wesm., bred by von Siebold. 



Habits and Habitat. — We have already stated that only females 

 of 8. lichenella are known, that, almost as soon as they emerge from 

 the pupa, they oviposit in the larval case, and that the unfertilised 

 eggs produced parthenogenetic young. Hamm obtains cases from two 

 fences near Wellington College, the colonies being about half a mile 

 distant ; the first, an old tarred fence, now almost lichen-covered, on 

 which many of the cases found are almost black, whilst the second is 

 an old railway fence without any covering, except the green lichen 

 that has grown on it, the cases on which are much paler and grey- 

 green in colour. Almost all the cases were found at the foot of 

 fences, but some on pieces of dead wood, and a few on stones. 



* Chapman notes that certain Herefordshire pupae which have been referred to 

 S. inconsjricuella have two hairs at base of labrum, on either side, and two (or one) 

 others above Jhese ; those of S. lichenella, from Wellington College, have the two 

 basal ones, rarely one above, and sometimes lose even one of the lower ones. 



