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under Side of one of the slender single-bud stalks, at a point about 

 one third of its length from the crown of the main stalk whence the 

 bud stalks spring. But occasionally a more advanced head is 

 selected, the buds of which have separated from each other, and the 

 total circumference of which is consequently increased, so that the 

 butterfly resting on the top of the head of buds cannot reach the 

 stalks of the lowest row with her abdomen ; but the position on the 

 stalk, rather than the particular stalk, appears to be the object she 

 has in view, for she then thrusts her abdomen in between the buds, 

 and thus attains the desired position on the stalk for depositing the 

 egg. Generally one egg only is laid on a head of buds, but occa- 

 sionally two or even three or four are so deposited. 



I. 2. C. argiolus depositing ova on young, and on more 



advanced, lieads of flower-buds of ivy. 

 3. 4. C. argiolus larvje resting on flower-buds of ivy. 



In about a week ihe eggs hatch ; the young larva in coming forth 

 breaks away a considerable portion of the crown, but leaves the 

 remainder of the shell intact and firmly attached to the bud-stalk. 



What then became of the minute larva, and how it fed, I for some 

 time had great difficulty in determining, and had it not been for an 

 accident I should probably have arrived at the erroneous conclusion 

 that in its earlier stages it entered the buds for both food and shelter. 

 There was no great difficulty in finding a minute hole in one side of 

 the bud ; but as the larva that had evidently made it did not appear 

 to be visible anywhere in its neighbourhood, the natural conclusion 

 was that it had gone inside. I therefore determined to open one of 

 the affected buds, and on doing so found only slight signs of feeding 

 having taken place on the soft inside of the bud near to where the 

 hole entered, but no larva was there. On releasing the bud, how- 

 ever, I found what appeared to be the mangled remains of a larva 

 adhering to it. Further heads of buds with egg-shells attached were 

 therefore examined with still greater care, each separate bud and its 

 stalk being scrutinised under a lens, with the result that I beheld 

 one of the most remarkable cases of protection afforded to a larva 



