394 



FAM I LV C U RC U LION I DAE 



Fu;. 265. 



The pupa is white, elongate, and narrow or squat and thick, and is 

 usually recognizable as a curculionid pupa by the 

 ^"^^' presence of the elongate soft rostrum. 



Some of the grubs of this family build a cocoon ,/<Al^^+Hf^ 



before pupating. This cocoon 



Cocoon. is usually made of fibres taken 



from the plant in which the 



grub has been living. The cocoons vary greatly 



in shape, and often fit closely into a bore or hole 



eaten out specially for their reception at the end of 



or to one side of the larval gallery. 



A systematic study of the Curculionidae of 

 the forests by Indian foresters is much needed. 

 Not only will such a study be fruitful in yielding 

 a large number of forms at present unknown to 

 science, but it will enable the exact position and 



importance of the family and its economic place in r^... „,jd pupa^^^ U«= I'aln, 

 the forest to be understood. fcrnigiiteus). India. 



The weevils are a large family of beetles, containing some insects 

 known to be pests of the first importance. It has already been definitely 

 ascertained that one genus at least, CryptorJiynchus, contains Indian forest 

 pests of the first rank. And the genus does not confine itself to the 

 conifer or the broad-leaved tree, as is the case with other groups and genera 

 of forest beetles. Both conifers and broad-leaved trees are infested by 

 different species of this genus in India. 



The habits of the weevils are varied, the insects of the family infesting 

 and damaging the bark, wood, stems, shoots, leaves, flowers, fruits, and 

 seeds of forest crops. The damage is done primarily by the grubs tunnelling 

 in the interior of the plant, but in some groups consider- 

 able defoliation is accomplished by the insect in the 

 mature state, either directly for feeding purposes, or 

 indirectlv, as in Apodcnis, for the purpose of egg-laying 

 and to provide food for the offspring. The weevils of 

 these defoliating groups cut the leaf across on either 

 side to the midrib, lay an egg near the apex of the leaf, 

 and then fold and roll the leaf up into a tight elongate 

 cylinder, which dries and forms food for the grub which 

 . l/>o</,-r//ssiss//, Msh\. hatches inside it (cf. figs. 281, 282). Others, more serious 

 Changa Manga. pests, oviposit in the bark of the main stems, main roots, 

 and large branches of green trees, their grubs eating out long galleries in the 

 green bast. This group of the family is of the greatest importance to the 

 forester, and a knowledge of its habits is essential to the correct preparation 

 of working plans. Some members of the already mentioned genus Crypto- 

 rhynchits, for instance, pass their lives in this fashion, appear to be immune 



