438 BRITISH LEPIDOPTERA. 



ending just past middle of 3rd abdominal segment shows Poulton's 

 line well, except in some specimens, in which it is covered by 

 forewing ; the outline of forewing shows a sinuation of hind margin, 

 somewhat nearer apex than middle, and a rounded fulness of anal 

 angle ; the wing just reaches the hind margin of the 4th abdominal 

 segment. The head, thorax and appendages are dull but fairly 

 smooth, their sculpturing being fine wrinkles ; the abdomen is smooth 

 and polished, its sculpturing being entirely pitting, except in the 

 cremastral region ; there is a fine suture dorsally along the thoracic 

 and 1st abdominal segments. On dehiscence, this suture opens 

 to a varying degree in different specimens, sometimes to middle of 

 mesothorax only, or as far as posterior margin of mesothorax, but 

 not into abdominal segments, where suture is only apparent, and the 

 head- and leg-covers fall away in one piece. There is much 

 variation in colour, some being very deep black, with strongly 

 contrasted, brown, intersegmental membrane, others a moderately 

 deep brown, against which the intersegmental membrane shows but 

 a trifling difference. The thoracic spiracle is a comparatively wide 

 opening, with sharp edges ; it is not, however, wide enough to 

 enable the true spiracle within to be seen ; the abdominal spiracles 

 have sharply raised, narrowly oval, ridges as their margins. There 

 is considerable variation in the sculpturing of individual specimens ; 

 the legs always have some transverse wrinkles, but sometimes these 

 are nearly invisible ; similarly on the antennae each joint has two 

 transverse lines, sometimes these are only indicated ; when this 

 is the case, there is usually one sharp point centrally on 

 each joint, in other cases the two lines are rough and 

 most marked at the margin ; on the prothorax the roughness 

 is formed by small irregular compressed elevations. On the meso- 

 thorax the ridges are dorsally transverse radiating from the 

 median suture ; there is another smooth line running longitudinally 

 backwards from the anterior margin of the segment at a point 

 half-way from dorsum to spiracle ; this is more than a mere 

 line and expands in middle of segment to a small smooth patch ; 

 it sometimes reaches posterior margin of segment ; sometimes the 

 wrinkles on either side of it coalesce and obscure it at this margin ; 

 a little way outside its lower end and at middle of wing-base 

 is another smooth spot with two or three isolated raised points, 

 sometimes wanting, sometimes very marked on little raised bosses 

 on very smooth pupa? in which the other wrinkling is very 

 obsolescent. On the metathorax the wrinkling is fine and of no 

 marked features, except the central suture, which is a raised 

 ridge, with a central deep impression (the true suture). The 

 abdomen has a very smooth polished surface with many rather 

 deep pits and sundry other marks and irregularities sometimes a 

 little resembling the wrinkling of the thorax, in others with 

 nothing but smooth surface and pits. As to the subsegmentation 

 in a well-marked specimen, one may define l\\e subsegments ; 

 anteriorly a rather broad and well-raised portion, best marked 

 on 3rd abdominal segment, then an extremely narrow one, usually 

 marked on the 5th abdominal, but often not very evident, a 

 third one of moderate width, the fourth much the same, and the 

 fifth, reduced to obsolescence dorsally, appears to be the inter- 



