45 



ance, which distinguishes it at once from the white mines made in 

 the same leaves by Chrysopora stipella. It is rather strange that 

 these two species, so closely allied, make mines of such divergent 

 characters. This point we shall touch on again later. 



The larva of C. hermannella in the fourth stadium continues mining 

 straight ahead, but as the mine is now a wide one and the larva's 

 course runs all over the leaf, it breaks into its own galleries and the 

 whole leaf often becomes one large blotch mine, though not originally 

 formed on the blotch principle. The larva mines very rapidly and 

 the severed cells keep the mine wet. The excrement is deposited in 

 an almost fluid state and adheres chiefly to the upper cuticle of the 

 leaf, hence the mine becomes clouded with green and black. If the 

 larva, after mining all over the leaf, has not attained its full growth, 

 it bites a hole generally through the lower cuticle of the leaf, comes 

 out of its mine, and crawls about the plant till it finds another suitable 

 leaf, which it enters and commences to mine in the new leaf in the 

 same manner as previously. 



In this fourth stage the larva makes altogether a mine of about 

 150 mm. in length, and usually requires two or three leaves for this 

 purpose, and about ten days is taken up in making this part of the 

 mine. Thus we see that it takes the larva some thirty days to feed 

 up, and that the total length of the mines is some nine inches. The 

 length and width of the mine is not at all a fixed quantity, some larvae 

 making wider or longer mines than others. I believe it depends 

 somewhat on the nourishment which each particular leaf affords ; in a 

 poor leaf the larva will have to mine over a longer space to obtain 

 the same amount of nourishment it would extract from a shorter mine 

 in a leaf of good condition. Three or four days before the larva 

 becomes full fed it loses all its green colour and becomes a clear, 

 pale yellow, which colour again changes to cream, and about thirty 

 hours before the larva finally leaves the mine reddish-brown spots 

 begin to appear on its body, and these gradually change to crimson. 

 Before quitting the mine the larva often wanders about inside the leaf, 

 biting here and there at the upper cuticle and spinning a few threads 

 on the lower cuticle. Finally it makes a slit in the upper cuticle of the 

 leaf, comes out, and wanders off to find a suitable place in which to 

 spin its cocoon. The crimson spots on the cream ground make it a 

 very handsome little caterpillar. 



Where the larva spins up in freedom I do not know, but it does 

 not seem to take kindly to earth or leaves. Those I have had made 

 no ditificulty of spinning up in a hole in a cork or in the angles made 

 by the sides and tops or bottoms of pasteboard boxes. The cocoon 

 is composed of fine white silk and is very tough. If it be opened a 

 few days after it has been spun the larva inside will be found to have 

 lost its cream ground colour and to have become all deep reddish 

 ochreous. There are two broods of this species, and those larvte 

 which spin up in September do not change to pupte till the following 

 April. They pass the winter as larvae in the cocoon. I examined 



