ON THE EMERGENCE OF LISTRODROMUS QUINQUEGUTTATUS, GEAV, 187 



of a somewhat more sordid colour than are the head, wings, and 

 abdomen. There is no trace of lateral abdominal spiracles, and those 

 of the butterfly's pupa, in which the parasite's ecdysis takes place, are, 

 like the whole interior of the chrysalis, thickly covered with a silky 

 coating, which would indicate a somewhat incomplete respiratory 

 system. Its length is 7mm. Shortly before emergence the imago can 

 easily be traced, since most of the markings, and especially the flavous 

 outer-orbital, are plainly visible. The pale marking on the three 

 basal segments is, however, not represented. The tumidulous post- 

 petiole is, nevertheless, very distinct, though the antennae, palpi, face, 

 and wings are still enveloped in their white covering ; the first of these 

 are flavous throughout at this stage, excepting the scape, which is 

 piceous. The abdomen has now undergone considerable modifications, 

 and its contour is quite changed. Nearly all the imaginal coloiiringis 

 present, excepting those points already noticed. 



As far as I am at present aware, LUtrodromns qmnqucf/7itfatiis con- 

 fines its parasitism to C'l/aniris ort/iohis, since it has been thence bred 

 by Marshall in August, from larvfe on Syrinf/a in July (cf. Ent. Mo. 

 Mai/., xxxiii., 235), by Bignell, and, quite recently, by Mrs. Redmayne 

 (antea, p. 164), and Mr. Prideaux. 



Pupa of Libteopeomus quinqueguttatus, Geav., ? . 



Fig. 1 represents the pupa, and Fig. 2 the abdomen, shortly 

 before emergence. 



There was no trace outwardly of any emergence at 12 noon — at 2.0 

 p.m. however, I heard a gnawing noise which could be distinguished at 

 the other end of the room ; it was similar, though scarcely as loud, as that 

 produced hjTrichiosoma when emerging. — This continued intermittently 

 till 4.0 p.m., when I found an irregular, jagged hole had been effected 

 through the C. anjiolns pupa, at about the apical third, through which 

 the flavous orbits of the parasite Avere plainly visible. — At 4.30 p.m., 

 the hole was much enlarged, and both antennae protruded. — At 5.15 p.m., 

 the two front legs and the head were through it, and the insect was 

 furiously struggling to lever up the cap, which had been (apparently) 

 insufficiently cut round, with its prothorax, and biting the shell about 

 its mouth, with occasional rests of a few seconds' duration. — At 5.30 p.m. 

 this was continued, and several attempts were made to bring the man- 

 dibles on to the cap, but, these proving futile, the shell upon the breast 

 continued to be demolished. — At 5.40 p.m., I raised the operculum, 

 fearing the struggle for freedom might be lasting too long for the 



