872 BRITISH LEPIDOPTERA. 



interior is green, with yellow lines beneath the dorsal humps, with 

 extensions inwards, giving, by various refractions, very curious and 

 marvellously beautiful effects. The dorsal view is an ovoid, with 

 a border of fifteen points on each side, very regularly spaced ; of 

 these, the anterior and two posterior belong to the dorsal series ; 

 two, three, four and five belonging to the meso- and metathoracic seg- 

 ments ; the ninth and tenth abdominals are without the lateral 

 humps. After the third moult, the arrangement of the spines is as 

 before, but the spinules are less distinctly developed, and the skin- 

 surface now becomes covered with minute spikelets. In the third and 

 fourth skins there also appear to be some glandular structures, which 

 have a dorsal and dorso-lateral position on each segment. With the 

 fourth moult the spines disappear. The spinneret of this larva is remark- 

 able until the penultimate stage. It is not a pointed organ, but is 

 flattened out like the tail of a fish, and the silk that the larva spins upon 

 which to walk is not spun in the form of a thread, but as a very long 

 ribbon (Chapman). The adult larva is of a bright pea-green colour, the 

 ventral surface closely appressed to the surface on which it rests, 

 the head retractile within the prothorax, and the thoracic segments 

 retractile within the 1st abdominal segment. When retracted the 

 head and thoracic segments are quite ventral, the abdominal segments 

 forming an oval dome. The abdomen, viewed from above, is divided 

 into three slightly concave areas, the dorsal, bounded on each side 

 by a raised, wavy, primrose-yellow, subdorsal ridge, and two lateral, 

 each bounded above by one of the subdorsal ridges, and below 

 by a similar yellow subspiracular ridge, which is in contact with 

 the object on which the larva is resting. The two, wavy, sub- 

 dorsal ridges are ornamented with crimson (" violet," Fenn) points, 

 placed one on either side of each segmental incision, and these ridges 

 are continued in front round the anterior edge of the 1st abdominal 

 segment, thus enclosing the dorsal area in this direction. This con- 

 tinuation is yellow edged with crimson. The subspiracular ridges 

 also unite with the dorsal ridges anteriorly on the 1st abdominal seg- 

 ment, and posteriorly on the anal segment. The anal flap extends 

 slightly beyond the ventral area of the body. The segmental incisions 

 form, dorsally, conspicuous curved lines of a yellowish tint. The 

 ventral area is glaucous green. The head is smooth, shiny, pale 

 green, with brown mouth-parts, shiny, black ocelli, and bears a few 

 pale hairs. The thoracic segments are green, and on the venter of 

 the prothorax, placed laterally, is a comparatively large flesh-coloured 

 circle, enclosing a raised, cream-coloured, bluntly conical centre (and 

 having the appearance of painted wood). This is, perhaps, the pro- 

 thoracic spiracle. The 1st abdominal segment is of a bright orange 

 colour edged with crimson anteriorly. The skin of the abdominal 

 segments dorsally is composed of a large number of transparent warts, 

 the transparency being best seen where they form the lateral margins 

 of the body. The ventral edge of the body (lower than the subspi- 

 racular ridge) is white when appressed to a glass slide, and closely 

 resembles in this respect the white suckers on the first eight abdominal 

 segments. Of these, the suckers on segments 4-7 are much the better 

 developed. These suckers are very complex, and occupy on these 

 segments exactly the same position as ordinary prolegs, with which, 

 indeed, they appear to be homologous. The abdominal spiracles arc 



