332 BRITISH LEPIDOPTERA. 



for half its length, then more rapidly, reaching its greatest thickness 

 2mm. from the extremity, terminating very abruptly just before the 

 recurved tip, and so is very clubbed. The thickness of the $ antenna 

 is about o*4mm. near the base, 07mm. at the club, that of the $ is 

 about o'9mm. throughout. There are just over 60 joints in the shaft, 

 and about 12 in the curved tip, this seems to be substantially the 

 same in both sexes. The scaling differs in the two sexes, in the 



°. it preserves, almost typically, the ordinary Sphingid scaling of 

 three rows of scales of which one is very narrow ; the broadest or 

 terminal row on each joint is usually white and all may be, 

 the others are, however, usually of dark, pale and white scales 

 irregularly mixed. The $ antenna has the terminal row of long 

 scales paler than the others and sometimes white, but 

 the general rule is for the $ to have in this row and the others a 

 larger proportion of dark scales. The other rows of scales on the 



$ antennae are very much mixed up on the nearer part of the shaft, 

 so that definite rows hardly exist, but appear to result from three 

 or even more rows becoming irregular; beyond the middle, however, 

 they are arranged in three quite definite if not very smoothly arranged 

 rows. There is thus one extra row of scales on the $ antenna, 

 with a tendency for them to lose their definite arrangement. 

 The first tibiae and their spurs appear to be almost exactly alike 

 in the two sexes, a very slight advantage in size and development 

 of the $ may exist, but the evidence of it is not greater than the 

 frequent variation in size of the insects themselves might account 

 for. The wisp of hairs forming the scent fan of the $ arises from 

 the margin of the ventral plate just below the 2nd spiracle. The 

 hairs are about 5mm. long but the fan is not copious. The area 

 of origin is about imm. long by -3mm. wide (Chapman). Bartel 

 notes {Pal. Gross-§chmell., ii., p. 40) : "The 2 is distinguished from 

 the $ by the forewings being of a lighter colour and with weaker 

 markings ; the whitish spot at the end of the discoidal cell is also 

 much duller, smaller, scarcely surrounded with black, so that it fades 

 off into the ground colour/' 



Gynandromorphism. — The following are the described gynan- 

 dromorphs of this species that we have so far met with : 



a. Right side S , left side ? . Antenna and wings on the right side # 

 on the left side ? . The right eye larger. The body on the right side visibly 

 shrunken (Ernst, Pap. d' Europe, hi., p. 123, pi. cxxii., tig. 114 I), 



/3. Right side s , left side % . Perfectly halved as to antenna?, thorax, 

 wings and abdomen. Captured near Munster (Altum, Stett. Ent. Zeitg., i860, p. 91). 



7. Left side $ , right •? . Right antenna ? , left d . Right eye smaller. 

 The grey median stripe of the abdomen bends out in a curve on the right and 

 curtails the rose-coloured transverse stripes, one of which on the right side is absent ; 

 abdomen somewhat crooked. As to the rest the <? sex is predominant. The 

 ? wings are somewhat smaller, the costa of the forewing more arched, their colour 

 somewhat darker than usual, approaching that of the <$ . Thorax of S coloration, 

 the right patagia shorter, though similarly coloured. Captured near Munster 

 (Altum, Stett. Ent. Zeitg., i860, p. 91). 



f>. Right side <S , left ? . Wings and antenna on the right side s , on the 

 left ? (Pierret, Bull. Soc. Ent. France, 1842, p. liv). 



t. Left side J , right side ? . Halved gynandromorph. Abdomen 

 asymmetrical. In coll. Forstakademie, at Kberswald. [Perhaps the same as y.J 

 (Eckstein, Ber. d. Oberhess. Ges. f. Natur- und Hcilkande, xxvi., p. 3, pi. ii., 



fi g-3)- 



£. Lelt side i , right side ? *. Perfect gynandromorph. Left $ forewing 

 shorter than the right ? wing. Left S antenna strongly ciliated, larger than the 



