STRYMONIDI. 137 



This sex-mark has been described and figured by Aurivillius, with the 

 neuration of the $ and ? for this portion of the wing, as it is found in 

 Edwardsia w-albnm (Kon<j. Svensk. Vet.-Akad. HandL, v., p. 21, pi. ii., figs. 

 13-14). He also figures (op. cit., figs. 12, 15) the androconia (much 

 magnified), and the mode of attachment of an androconial scale to the 

 wing-membrane. We may here note that the peculiar half-scales 

 which are noticeable on the underside of the Callophryid species 

 (rubi) (antea, p. 91), are aiso present in the Strymonid {iv-album, pruni, 

 etc.), but are quite wanting in theEuraline, species (quercus,betulae, etc.). 



We have already noted the specialised characters of the eggs ; it 

 may be here remarked that, in most, if not all, of the Strymonid species, 

 both Nearctic and Palaearctic, the egg goes through the winter ; the larva, 

 however, is quite fully-formed within the egg-shell during the greater 

 part of the hybernatingperiod, andean be removed therefrom in January, 

 at least in some species, and continue to live dormant, outside the shell, for 

 a considerable time. As with our own species, the eggs. of liparops and 

 other Nearctic species are laid on a branch or twig near a leaf-bud, or 

 at the base of a leaf -scar, that of liparops on AmelancMer canadensis, 

 etc. This special mode of hybernation in the egg, of the Strymonid 

 species, is to be contrasted with the Callophryid (Callophrys, lncisalia y 

 etc.) method of hybernating as pupa. In its mode of hybernation, 

 however, the Strymonid group agrees with the Kuralid (sens, restr.). 



The Strymonid larvae are somewhat oval, seen from above; the 

 ventral area is flattened, the dorsal ridges exceedingly w T ell-marked, 

 higher in front than behind, the anal segments somewhat flattened, the 

 larva generally green in colour, with oblique lateral stripes. They are 

 remarkably supple, and have a peculiar gliding motion, and mostly 

 live on the leaves of forest trees, woody shrubs, etc., although there 

 are, perhaps, some exceptions. Scudder notes the New England 

 species liparops as feeding on whitethorn and plum, calanus and 

 edwardsii on oak, acadica on willows, etc. The larval stage is a 

 comparatively short one, March to June being, perhaps, the usual 

 length of larval life, and the species are almost all absolutely single- 

 brooded. The change of colour that one notices in the larvae of 

 most of our European species just before pupation, is paralleled in 

 North America, where we learn that liparops changes from green to 

 pinkish-brown, whilst the grass-green of acadica becomes purplish, etc. 

 The larvae of our British species will eat newly-formed pupae of their own 

 species with avidity. Scudder observes that the larva of T. calanus is 

 a cannibal, and will, when short of food, devour its younger and 

 weaker brethren. The gliding movement of the larvae, noted above, 

 is common to the species of both the Old and New Worlds, and one 

 is much reminded of our own species by Scudder's remarks of the 

 larvae of acadica, viz., that they are very supple in their movements, 

 their body curving like that of a snail, as they pass from one leaf to 

 another, or from the upper to the under surface. 



The pupa is plump, rounded anteriorly and posteriorly, the 

 thoracic segments making one large swollen mass dorsally, and the 

 abdominal segments another, the 1st abdominal segment forming a 

 conspicuous waist, separating the two bulging areas from one another; 

 they are abundantly studded with short, slender, serrated, and pointed, 

 hairs (see pl.iii.,fig. 1), very different from the Ruraline, trumpet-shaped, 

 type, as repesented by those of Bithys querciis (pi. hi., fig. 2); they are also 



