240 BEITISH LEPIDOPTEEA. 



scattered colourless bristles, mouth-parts pale brown, ocelli black, the 

 lenses flattened and surrounded by a slightly raised rim ; the chitin of 

 the head covered with a polygonal reticulation as of close fitting cells ; 

 the prothorax wider than the head, dull black, almost entirely covered 

 from the legs upwards with a glossy blackish-brown corneous shield, 

 subdivided medially by a narrow triangular patch of the ground colour, 

 the apex of the triangle placed anteriorly ; the mesothorax is rather 

 wider than the prothorax, dirty white in colour, but almost covered 

 with a similar, but much narrower, corneous shield, divided medially 

 by a pale line (a continuation of the pro thoracic triangular patch) ; 

 the metathorax and 1st abdominal segments slightly less than the 

 mesothorax (under certain aspects there looks a distinct waist), the 

 metathorax carries a small glossy corneous plate on each side, but no 

 dorsal one ; the abdominal segments gradually enlarge until they 

 obtain their greatest width at the 4th abdominal segment, and then 

 gradually decrease to the somewhat rounded anal segment, which is 

 surmounted by a black corneous anal plate. The true legs are brown- 

 black, corneous, very strong, each carrying a pale brownish claw, the 

 joints furnished with a ring of rather long whitish hairs. The 

 abdominal segments are of a dirty yellowish or brownish colour, * the 

 skin appears to be finely shagreened, the segments somewhat darker 

 posteriorly, the segmental incisions very strongly marked, each seg- 

 ment more or less capable of being drawn for a short distance into 

 that preceding it. The prolegs are very short on abdominal segments 

 3-6, the anal pair moderately large and strong ; all are provided with 

 an almost complete oval of black hooks (17 or 18 in number), much 

 wider and stronger on the anterior half, the oval broken on the inner 

 edge (hence somewhat horseshoe- shaped) ; those on the anal prolegs 

 stronger, have almost twice the diameter of the others, and are placed 

 much nearer together, not more than half their diameter apart. Each 

 of the dorsal tubercles consists of a very minute leaden-coloured, shiny, 

 chitinous button, carrying a large, shiny, glassy-looking seta, the 

 anterior (i) considerably farther from the median line than the 

 posterior (ii), but so far as the abdominal segments are divisible into 

 two subsegments, i is on the anterior subsegment, and ii on the 

 posterior ; iii is supraspiracular ; iv and v are both subspiracular, 

 and vi below the latter. The anal segment carries eight long, glassy- 

 looking hairs (sets), and suggests a double segmental origin. The 

 spiracles are very small, and form a little black ring with a pale centre 

 and surrounded by a paler area, and appear to be situated well on the 

 protuberant lateral flange ; the latter is very conspicuous. [Larva? 

 sent by Mr. Luff, March 18th, 1899 ; obtained on lichen-covered stone 

 walls in Guernsey. Described March 20th, 1899.] Bacot adds that 

 the larva has a slight constriction between the thorax and abdomen 

 when viewed laterally, and the thorax and head make up half of the 

 total length of the larva. The head is partly retractile within the pro- 

 thorax, the latter being longer from front to back than the meso- or 

 metathorax. The skin of the abdominal segment is much wrinkled 

 and granulated, a well-marked lateral ridge extending to the meta- 



* De la Voye and de Reaumur give the colour of the full-grown larva as black or 

 blackish-brown, occasionally pale brown. To the naked eye this would be so, but 

 under a microscope the ground-colour appears to be much paler. 



