1922.1 9 



the pyriform outline and becoming oval. This egg showis, as well a."* that of 

 any sawtiy, how it grows by imbibing fluid from the leaf-tissues with which it 

 is in contact, increasing its bulk perhaps five or six times. All the other 

 species I refer to in these notes have eggs that perish if the sap fails where they 

 are laid, though I think none of them grow appreciably, but all apparently lose 

 fluid and die if the supply from the leaf fails. The egg of ctirtispina is also 

 much larger than these others, and being in a pocket can hardly belong to a 

 species congeneric with those that lay exposed eggs, like ribesii. Even when the 

 egg has grown to its full size with much of it exposed and the covering- cuticle 

 becoming brown, any attempt to remove and isolate it results in its rupture 

 and destruction. This firmness of attachment, which exists also in the 

 exposed eggs of many species of " Nematini," to the surface through which 

 they draw fluid and nutriment, suggests a union between the egg and the plant 

 that might almost be called placental. 



The egg is usually deposited on the leaf just beyond and parallel with a 

 secondary nervure at about its middle, but it may be otherwise placed and 

 oriented. Though in my jars confined space led to several eggs being placed 

 on one leaf, I feel sure that each egg was, so to speak, a separate laying, and 

 that naturally only one egg is deposited on a leaf. This is confirmed by the 

 larvae always being found solitary. 



The eggs hatched at the end of a week (weather very warm), and in a 

 further ten days the first larva spun up. The young larvae are very dark, the 

 venter pale, but the back and head appear to be quite black. Thej'' eat the 

 margins of the leaves, holding on by the true legs, the body stretched out free, 

 slightly away from the leaf, with the last segments bent slightly ventrad ; it 

 would hardly be inaccurate to say that the body was straight — length 2 mm. 

 When not long hatched and having only fed a little, the head would be 

 called dark brown and chitinous and the back very dark green, less dark as 

 they feed, due to expansion and not to intestinal contents. 



In the 2nd instar the larva has the head brown with a slightly 

 darker shade behind the eyes, the body green, darker above, paler below, 

 this as seen with a lens. To the unaided eye the colour is a rather dirty olive, 

 no white dorsal line or any other variation being visible. It keeps nearly the 

 whole body close to the leaf-margin or edge of eaten portion. The supra -anal 

 forks stand well back, with dark tips, as they did in first instar. When 

 disturbed, the body is thrown away from the leaf with a jerk, but not further 

 than to leave it still almost straight. 



The larva in this (2nd) instar varies from 4-7-6'0 mm. in length, and it 

 then moults into the last instar. I could not obtain any evidence that it had 

 more than two moults and three instars. It now, in last instar, has the double 

 white dorsal line ; its habits of feeding, etc., seem to be the same as in previous 

 instars. When full grown the larva is 13 mm. long, fairly cylindrical, perhaps 

 rather thicker about 8rd and 4th abdominal segments; width about I'Smm. 

 With its ventral surface along the edge of the leaf, the last segments are only 

 turned ventrad if the straight surface is not lengthy enough. The colour is 

 pale apple-green, slightly paler below, tracheal white line obvious. Owing 

 to the continual rather quick pulsation of the dorsal vessel, the two portions of 

 the white line (subcutaneous) appear to approach and recede from each other. 



