AOIDALIA. By L. B. Peout. 71 



Forewing beneath in ^ rather darker, more or less strongly sprinkled with fuscous atoms ; both wings beneath 

 with the cell-spot and outer line placed about as in pudicaria, the (J also with the subterminal markings of 

 forewing more or less developed. {^ antenna with longish ciliation; hindtarsus fully one-half as long as tibia. 

 Egg almost perfectly cylindrical, the ends only slightly rounded; about 15 powerful longitudinal ribs, the 

 transverse ribs exceedingly fine, about 15 — -18 in number; delicate greenish-yellow, becoming after 2 days 

 pale pink with scattered crimson spots. Larva rather slender, nearly cylindrical, tapering towards the head, 

 the subsegmentation distinct; grey-brown with fine pale medio-dorsal line, its fine dark edges thickened 

 into black dashes at the ends of the segments; an ill-defined dark supra-spiracular line and a rather pale 

 lateral stripe containing the black spiracles. On Valeriana officinalis, Spirasa ulmaria and other plants. Pupa 

 pale brown with the wing-cases more greenish. The moth appears in July, frequenting marshy places, damp mea- 

 dows or daTip places in woods. It sits by day among rank grass and is easily disturbed. Widely distributed in Cen- 

 tral andNorthern Europe, N. Spain, Italy (except the south), Croatia, S. W. Russia and Armenia ; also reported from 

 Amurland. — ab. myrtillata Dadd is a somewhat whiter form, nearly as clear as caricaria, the dark shading myrtillata. 

 on each side of the subterminal almost entirely wanting, the entire area distally to the postmedian line being 

 therefore virtually without markings, at least on the forewing. As the original specimens on which the name 

 was founded (taken in the Berlin district) appeared rather broad-winged, with distal margin straighter 

 than usual, the apex therefore appearing more pointed, and showed a few other slight differences, and were 

 taken among bilberry apart from immutata, they were at first believed to represent a separate species. Sub- 

 sequent experience, however, has not confirmed this and I regard the type-spscimens, which were very 

 kindly sent me by Mr. Dadd for examination, as representing quite clearly an aberration of immutata. I have 

 taken the same form in Essex in company with typical specimens and far away from bilberry. — syriacata syriacata. 

 Neuburger, described as a variety of immutata, is unknown to me. It is said to be smaller, brownish (light 

 fawn-colour), the lines well expressed, particularly the two which border the subterminal. Underside somewhat 

 glossy, more uniform than in the type, the forewing not darkened. Taken in the Lebanon. 



A. corrivalaria Kretschmar (= sylvestraria var. H.-Sch.) (4 k). Forewmg shaped about as that oi corrivalaria. 

 immutata or with the apex slightly more prominent, hindwing more bent in the middle (not shown in our 

 figure). The average size is smaller than that of irnmutata, the colour more brownish than in even the ^(^ 

 of that species, the lines, discal and terminal dots similarly arranged, the discal dot of forewing nearly 

 always well developed. Forewing beneath with the median line or shade usually well develloped ; hindwing 

 beneath with the true postmedian line present (as in floslactata), the line beyond it usually less strong, 

 or obsolescent. (J antenna somewhat thicker, the joints a little swollen, the ciliation longish. ^ hindtarsus 

 relatively a little shorter than in immutata. The egg is pale yellow when first laid, becoming rose-red in two 

 days; I known of no more detailed description, but it will doubtless prove that the red colouring is arranged 

 in blotches, as in nearly all the species. The larva is very slender with the head rather small, the lateral 

 ridge rather strongly developed, the spiracles black ; the ground-colour is light grey mixed with yellow, with a 

 double dark dorsal line and fine light lateral line, the ventral area blackish with light longitudinal line. The 

 moth flies in June and July and inhabits damp meadows. It sits by day deep down among long grasses, 

 resting with outspread wings on the upperside of leaves of Caltha, Ranunculus, Lythrum, etc., and the $ 

 is not readily disturbed. The flight is slower and less long-sustained than that of immutata. corrivalaria 

 is an extremely local species. In Europe it seems to be restricted to Holland (Limburg), N. Germany and 

 the St. Petersburg district. According to Staudinger it reappears in Eastern Siberia and Korea and is per- 

 haps represented by a local race in Japan. I have not seen examples from any of these latter localities. The 

 range of variation is very slight. Snellen says that his Dutch examples are darker than the N. German 

 which were sent him by Zeller. 



'■ < A. pallida Warr. (= peralba Sivinh.), erroneously recorded by Butler in the "Illustrations of Hetero- pallida. 

 cera in the British Museum" as sylvestraria Hbn., has the wings, especially the forewing, considerably narrower 

 and rather more glossy than in immutata L., its weakest-marked forms recalling on the upperside PtycJio- 

 poda subsericeata Haw. almost more than any Palearctic Acidalia with which I can compare it, though it is 

 larger than the species mentioned, the forewing with distal margin more oblique, apex more acute, the markings 

 stronger, black discal dots present, etc. The neuration is quite normal. The ground-colour of the wings 

 is approximately the same as in the $ of immutata, sometimes even purer white or with a faint suggestion 

 of a bluish rather than a yellowish tinge. The lines are slightly more greyish than in immutata, the median 

 shade oblique, on the hindwing usually placed much proximally to the discal spot, the white subterminal 

 line rather broader and more nearly straight. Discal dots on an average smaller. Under surface much 

 more strongly glossy than in immutata, the forewing suffused (not speckled) with more reddish brown, paler 

 between the median line (which is ill defined) and the postmedian, darker distally, the broad white subterminal 

 therefore conspicuous. Hindwing beneath more nearly as in immutata but without the sparse dark speckling. 

 Structure not essentially different from that of immutata, the (J hindtarsus longer in proportion, not much 



