1890.] THE YOUNG NATURALIST. 



25 



very pale straw-colour, faintly tinged with green, the large ocelli in. 

 tensely black, and consequently very conspicuous, the mandibles red- 

 dish-brown, frontal and small anal plate of the same bright green as 

 the ground-colour, the dark green (slightly brownish anteriorly) pul- 

 sating dorsal vessel forms the dorsal stripe, between it and the spiracu- 

 lar region are two greyish-white stripes, on which the small black 

 tubercular spots may be seen ; below the spiracles is a still clearer and 

 more conspicuous white stripe ; spiracles black. Ventral surface uni- 

 formly of the same bright green as that of the dorsal area, at the front 

 and at the base of each anterior leg, is an intensely black spot, and the 

 prolegs are finely margined with black. 



"Feeds in the shoots of yarrow, apparently preferring the central 

 shoot, and eating downwards towards the root." (" Entomologist's 

 Monthly Magazine,' Vol. XXII., pp. 103, 104). Mr. Porritt then 

 adds : — " It will be noticed from Mr. Buckler's description of the 

 larva of P. dichrodactylus ("Entomologist's Monthly Magazine," XII., 

 233), that both species correspond in having three forms of colouring 

 in the different stages of growth, and the resemblance of the adult 

 larvae particularly, shows the close relationship of the two species, 

 whilst the differences, apart from the food-plants, are sufficiently 

 wide to separate them." 



Pupa — The pupa is external and fastened to a leaf or stem of the 

 food-plant by its anal segment. Mr. Porritt thus describes the pupa :- 

 " The pupa is a little over half an inch long, and exactly of the shape 

 of that of dichrodactylus as described by Mr. Buckler, though perhaps 

 a little stouter, as it can hardly be called " slender," the word applied 

 by Mr. Buckler to that species. It has a longish beak in front, pro- 

 jecting at a slight angle downwards from the head, pointed at the tail, 

 the wing-cases of moderate length, well developed, and the ends of the 

 leg-cases projecting free from the abdomen. The colour is bright 

 pale green, dorsal line darker green, edged on the thorax with white, 

 beak white above, rust colour at the sides, there is also a conspicuous 

 streak of this rust colour on the hind part of the thorax, and the same 

 colour also appears (but more faintly) on the abdominal point, and at 

 the tip of the leg-cases ; sub-dorsal line dark green ; lateral line white. 

 Ventral surface pale green, with darker green, and the wing-cases with 

 whitish rays." (" Entomologist's Monthly Magazine," Vol. XXII., 

 pp. 104, 105). 



