154 Keiv : Weevil-Cocoons of the Fig-worts. 



impression is that the matter is oozing - from the skin, the little 

 larva appearing- to be altogether inactive. Observing with 

 a lens, however, one finds that the mucus is being slowly shot 

 out, at stated intervals, in short thick jets, from the anal nipple, 

 not upon the median line of the back, but laterally, the nipple 

 being extended first towards one side, then towards the other, 

 in strict alternation. The head of the animal is motionless, and 

 the only sign of activity, other than that exhibited by the nipple, 

 is a sligfht muscular movement observable on the body. The 

 mucus is passed forwards and distributed, evidently by the 

 muscular movement just mentioned, and it gradually dries, 

 every part of the animal being ultimately covered with a .regular 

 membrane. After a time, when this membrane is complete and 

 sufficiently dry, the larva detaches its body from it ; and detach- 

 ing- its ventral surface from the plant, it assumes a curved 

 position, the head and the tail being close together. The 

 shape of the animal is now almost globular ; it has doubtless 

 lost some of its bulk from the continued discharge of. mucus; 

 and it is evidently hard at work moulding- and stretching the 

 covering. The result is that it finds itself free within a mem- 

 branous, more or less spherical, investment, which must now be 

 called a cocoon. The structure is sufficiently translucent for 

 some time to enable one, by holding it to the light, to observe 

 the proceedings of the enclosed larva. The creature is observed 

 to be working with its head and mouth, and it is clearly seen at 

 regular intervals applying to the anal nipple, taking away 

 a mouthful of mucus, and working it with much diligence into 

 the walls of the cocoon. After about an hour the structure is 

 noticeably larger, and the animal has now room to move about 

 freely within ; it constantly changes its position, but always has 

 its back pressed against the membrane, and it is in this manner, 

 and by pressing with its head, and at the same time adding, new 

 material that the structure is enlarged and given its proper 

 conformation. The larva continues for many hours to increase 

 the substance of the membrane, but without making it thick or 

 wholly opaque, and during all this time the regular applications 

 to the nipple for mouthfuls of mucus are kept up. An individual 

 which began to form its cocoon about mid-day, commenced this 

 part of the work at 9.30 p.m., was continuing it at 11.30, and 

 when I left the creature at 8 a.m. on the following morning 

 it was still at work, still taking mouthfuls of mucus, and 

 laboriously applying them to the walls of the cocoon. Even 

 at this time, by properly arranging the light, I could not only 



Naturalist, 



