FAMILY CERAMBYCIDAE 327 



pupal chamber against the attacks of predaceous foes are also well shown 

 in the latter plate. The illustrations are from photographs taken in May by 

 Mr. W. F. Perree of a green tree felled in the forest in February 1906. Both 

 boring grubs and one or two beetles just ready to emerge were found in 

 it; also some pupae taken from the wood in April 1906. To ascertain the 

 number of larvae which reached maturity, I examined on 30 May a green 

 tree felled near Rajabhatkhowa on 15 F'ebruary. From a circular section 

 of a log 15 in. long, taken midway up the length of the bole, 60 grubs of 

 various sizes up to apparently nearly full-grown were cut out, this number 

 giving 2,840 grubs in the 55-ft. bole of tree. The tree proved a fair 

 example of a badly attacked one. Larvae examined when boring down into 

 the heart-wood and excavating the pupal chamber were found to contain in 

 their bodies a large amount of a peculiar white substance doubtless secreted 

 by them for the purpose of preparing the white calcareous covering to the 

 pupal chamber. 



The Pupal Stage. — Pupae have been taken from the pupal chambers in the 

 heart-wood in February (on the authority of the Range Officer), and one which 

 is probably this insect on 28 April. I think it possible that the insect 

 pupates about February in the case of the beetles issuing in May-June; but 

 in the case of those issuing in March it would probably pupate in November, 

 and for those issuing in the autumn (if any do so) in May-June. The pupal 

 stage is probably two to three months, varying according to the time of 

 the year when the larva pupates. 



The Beetle. — The insect on assuming the beetle form remains in a 

 resting condition in the pupal chamber, whilst the outer parts slowly 

 harden. It then breaks the calcareous covering, closing the mouth 

 of the pupal chamber {vide pi. iv), and makes its way up the broad larval 

 tunnel in the heart-wood, which is always free of wood particles, since whilst 

 boring it the grub probably feeds little and ejects from it the wood parti- 

 cles gnawed out, pushes or gnaws its way out through the mass of wood 

 refuse in the broad larval galleries in the sapwood, and bites its way out 

 through the bark, the escaping orifice always being a large one. 



The beetles invariably appear to leave the tree at night. Careful 

 inspection has never disclosed the fact of any beetle boring or pushing its 

 way out in the daytime. There seems, however, to be little doubt that 

 the beetles, although they do not take wing readily, are active on cloudy, 

 dull, rainy days, and that they pair a good deal in dark shady places in 

 the forest during the daytime. 



The observations carried out on the life history of this insect were com- 

 menced in Chota Nagpur in 1897, when it was first dis- 

 Life History In ^Q^r^^^^ as a pest of the sal. The larva was found and the 

 Central Provinces. ^ , 1 i r 



approximate date of pupation and the dates ot emergence 



of the beetles in considerable numbers in May and June were ascertained.* 

 * Injurious Insects of Indian Forests, 71 (1899). 



