318 [December, 



rushed out. The larva does not usually leave its dwelling without a little 

 pressure, though sometimes it seems to be off as soon as one looks at 

 it ; it hangs by a thread, but as soon as it reaches the ground it 

 generally wriggles and dances in a way that would put even a Tortrix 

 to shame. At the same time, it sometimes appreciates the advantages 

 of lying still, when it curls itself up, eo as to bring its head and tail 

 together, and then strongly resembles a small leaf of Cochlearia 

 broken off. 



A curious habit of the larva is, that when about to eject a grain 

 of frass, it gives its tail a succession of violent jerks, by the last of 

 which the grain is thrown to a distance of several inches. Mr. Hodg- 

 kinson suggests (Entom., 1S78, p. 11) that the full-fed larvse get right 

 into the seed-pods ; this is quite contrary to my experience at Portland, 

 as, though I looked carefully wath this object in view, I never found 

 one in a seed-pod. It is, however, possible that on plants with very 

 large seed-pods they are compelled to get completely inside, in order 

 to get at the contents; at Portland, the larger pods would easily 

 contain a larva, but the seeds could all be eaten by the introduction 

 into the pod of merely its first few segments. As a rule, there was 

 but one larva in a flower-head ; a second one would probably sooner 

 or later have come into contact with the first, and caused both to 

 depart suddenly. 



In the case of other solitary larvae, e. g., C. absynihii, of which 

 one rarely, if ever, finds two large ones on the same flower-spike of 

 wormwood, my impression is that a deadly conflict takes place, and 

 that the survivor eats its weaker or less active brethren ; in the present 

 case, however, it is the most sluggish which is most likely to retain its 

 position. 



The young larva is very like the older ones, but, perhaps, a little 

 more brownish in colour, and more transparent. When nearly full- 

 fed, it is about 6'" or 7'" in length, and tapei's towards the extremities, 

 when it is rather less than half the breadth of the 8th and 9th 

 segments, which are the largest in the body. 



The head is green, with a very slight shade of brown, and is much covered with 

 small blackish marks of irregular shape, which are placed in four more or less dis- 

 tinct lines on each side of the middle, in addition to the usual spots, which are 

 intense black. The 2nd segment has also numerous small blackish markings, not so 

 large as those on the head. The body is entirely green, with the exception of the 

 usual warts and bristles, which are jet-black and very conspicuous, so that the larva 

 presents a striking and somewhat formidable appearance under the microscope, par- 

 ticularly about the head and 2nd segment. When full-fed the larva becomes rather 

 more opaque in appearance, and spins a cocoon of very fine network, composed of 



