ACIDALIA. By L. B. Prout. 53 



far the variation is geographical, how far seasonal and how far individual. A short series which I possess 

 from Siccawei, near Shanghai, seems to point to its being in part seasonal, yet includes nothing so dark as the 

 form accurataria. It is not impossible that the forms represent more than a single species, but I see no reason 

 for thinking this probable, as they agree in all essential characters. All that is yet possible is to indicate the 

 essential structure, and then to describe the named -forms, leaving their exact status to be fixed hereafter. To 

 the characters given above it need only be added that the wings are but little narrower than in the ternata-giow^, 

 the distal margm of the forewing gently rounded, not very strongly oblique, that of the hindwing'rounded, 

 the costal margin slightly longer than the inner margin, but not nearly so strongly elongate as in 

 the lactea-gxow^. The second subcostal of the hindwmg is decidedly variable, even in forms from a single 

 locality; it may be either separate from the first radial, or rising from a common point or even longer-stalked 

 than is found elsewhere m the genus. The ground-colour of both wings is usually bone-colour, sometimes more, 

 sometimes less tinged with greyish, but with the colour variation produced chiefly by the degree of irroration 

 with fuscous atoms, which may be very slight or extremely strong. The dark lines and black cell-spots are also 

 very variable in the intensity of their expression; postmedian line usually more distinct than antemedian, 

 nearly parallel with the distal margin but with slight or very slight curves inwards in the radial and submedian 

 areas and usually accentuated by darker dots on the veins which, being placed rather at the distal side of 

 the line, somewhat suggest minute teeth in it; antemedian, when distinctly traceable, is seen to be bent or an- 

 gled in the cell, and is also sometimes marked with dark vem-dots, but is always wanting on the hindwing ; median 

 line or shade rather diffuse, almost straight, touching or nearly touching the cell-spot; distal area usually 

 somewhat darkened, the pale subterminal line then distinct, very slightly sinuous, not dentate. Under surface 

 ■ndth postmedian and subterminal markings and cell-spots mostly expressed, the basal area, especially of fore- 

 wing, more suffused and without definite markings. — impersonata Walk. (3 k) is the lightest form, the ground- w^jperaoxato. 

 colour not tinged with grey, the fuscous irroration slight and not very dark, the transverse lines moderately 

 distinct. Walker's types were from China (Fu-chau, according to the register at the British Museum) and are 

 in bad condition, but do not appear to differ appreciably from the forms occurring inChekiang and in the 

 neighbourhood of Shanghai and of Ichang, thus Palearctic. On the other hand two poor specimens from Ting-hai 

 (Fokien) and Formosa appear to have been of a rather darker, more ochreous shade. On an average these 

 light forms are rather small, and the dates, so far as available (Ichang, August ; Shanghai district, September), 

 suggest a second brood, especially as Dr. Culpin took a larger, darker form at Shanghai at the end of April. 

 Some of the localities given by Leech are erroneous, being due to mistaken identification. I have, however, 

 seen one Japanese example (Suma, 21 August, in coll. Wileman) referable here rather than to the form maces- 

 cens. — muscularia Stgr. is a very similar but light grey form, founded on a single (^ from Amurland. muscularia. 

 It is unknown to me, but is said to have the apex of forewing rather more acute than accurataria. Perhaps 

 really a synonym of impersonata. A pair from Gensan, Korea, July, rather lighter than macescens, may possibly 

 belong to it. — macescens Butl. (3 k) is of a medium, brownish grey, on an average larger than imfcr sonata, macescens. 

 the markings variable in distinctness. Japan, widely distributed. May to September; Shanghai in April; Chang 

 Yang in June; Tientsin. — accurataria Chr. (3k) is still darker, distinctly marked, the distal area particu- accurataria. 

 larly darkened, leaving a clearer space between median and postmedian lines. $ apparently smaller. Amurland, 

 July and August. 



A. gastonaria Oh. is very distinct m the very smooth, glossy scaling and pure white colouring, at least gastonaria. 

 in a distal band. Moreover, if my candicans is really a form of this species, the structural characters are not 

 quite identical; the palpus, though rather stronger and rougher-scaled than in typical AcidaMa, seems somewhat 

 intermediate and the tongue is long. I have not seen OberthOr's form, from Oran. It is variable in colour, 

 reddish brown or brownish, sometimes pale grey, the darker brown postmedian band as in our figured candicans, 

 followed by a narrow white band (or thick line), the extreme distal edge also white, forewing with a row of minute 

 dark dots between the veins. Abundant at Macta in April, hiding among scabious on the coast, in tolerably 

 sheltered places. — candicans subsp. nov. (5 b) from Algiers and its immediate vicinity seems to be a good local candicans. 

 race, or possibly a closely related species. All the examples which I have seen (both sexes) are rather smaller 

 than typical gastonaria with both wings pure white from the base to the brown band and the grey shade between 

 the two white distal liaes much weaker; the fringes in the ^ remain miore or less brownish; discal dots per- 

 haps less minute. Forewing beneath infuscated, except the white line beyond the band. The $ is still purer 

 white, but has the band slightly darker, though a little narrowed, discal dots minute, underside scarcely so 

 strongly infuscated. The neuration varies a little; the 1. subcostal of forewing does not always anastomose; 

 the 2. subcostal of hmdwing is sometimes very shortly stalked, sometimes separate. 



lactea-group. 



(J antenna with long fasciculate ciliation, sometimes arising from short pectinations; palpus short; 

 hindwing greatly narrowed, second subcostal separate {Lycauges Btlr.). 



