I 2 [January, 



do not taper to the Piids to any extent, i.e. nre not ovate, and carry their full 

 width very close to the ends, which, though crowded, have a very square 

 appearance, especially at one end. 



PteroJiidea oligosfilus Forst. 

 I find this larva on Osier, one at a time. Its habits are almost identical 

 with those of curtispina, and it is not very different from the larva of that species 

 before the latter attains its double dorsal white line. Length 12-13 mm., 

 width 1-6 mm. It looks very long and slender, widest about 1st abdominal 

 segment. Colour dark apple-green, very much the colour of the osier leaf on 

 which it feeds, uniform, except tliat the head is a little paler and has a dark 

 line down the dorsum and a brownish cloud above the eyes ; and the last 

 segment also differs in being yellowish, with dark orange central dorsal band, 

 ending in two short black (supra-anal) terminal spines. Feeds on edge of leaf, 

 like curtispina, and when crawling along it keeps its prolegs on the margins, 

 but the last segment is bent to upper or lower side of leaf as may happen. It 

 is fairly cylindrical, but rougliened by subsegmentation and lateral flanges, 

 so that viewed dorsally there seems dark coloration laterally', due, however, 

 entirely to refraction through the eminences, showing also that the larva is 

 translucent. The subsegments are difficult to count owing to similarity of 

 colour, but seem to be six in number, two wider in front and four narrower 

 behind. "When walking on the flat, the anal segments cannot apparently be 

 bent down, and it is apt to go to one side or the other. There are six pairs 

 of ventral prolegs, with anal and true legs = 20. The larva is always solitary 

 and always on the edge of a leaf. A mounted larva skin shows little structure 

 dorsally, but along the lateral region, above and below spiracles, there are 

 considerable areas showing minute fusiform plates, their margins outlined by 

 black dots and their central surface studded by very fine dots. They differ 

 from the similar cells of P. hypoxanthus in not being so definiteh- ranged and 

 extended transversely, and in being more pronounced along their margins. 

 There are a couple of solitary hairs behind each spiracle and a few on the last 

 segment. The antenna is nearly the same as noted in P. curtispina. The 

 cocoon is brown and made between leaves of the food-plant. 1 believe the 

 second brood goes into the earth, but not deeply. 



On July 21st, 1921, some bred females oviposited on the undersides of 

 Osier leaves, generally singly, two or three eggs near each other were probably 

 deposited at separate visits to the leaf. The leaves chosen are those just or 

 barely mature. The eggs are placed about half-way between the mid-rib and 

 the margin, usually parallel to the mid-rib, but now and then to the secondary 

 ribs. They appear to be laid on top of the small silky hairs with which the 

 underside of the leaf is so abundantly and closely set, though witliout a lens 

 the surface looks as glabrous, though not as polished below as above. 

 Magnified, however, it is seen that they are pressed down amongst the hairs, 

 which, rising up round each, somewhat obscure the margins of the eggs. When 

 an attempt is made to remove the egg it is found to be firmly fixed, probably 

 by inclusion in an incision, as in ribesii, jmvida, etc., nor can they be removed 

 without almost certain destruction. I did not succeed in hatching any, the 

 leaves withering before the eggs had matured. They are 0-92 mm. long and 

 0'3 mm. broad, of the usual spindle shape. 



