INSECT LIFE IN INDIA AND HOW TO STUDY IT. 119 



needle ; from four to six weeks are spent in the larval stage. The 

 pupal stage is a short one, and about the middle of June or beginning 

 of July the tiny brilliant metallic blue flies shown in fig. 36, b, issue. The 

 length of this insect is *th of an inch onlv. The attacked rosettes 

 turn yellow and die, and occasionally a considerable amount of defoliation 

 is accomplished in this manner on young deodar saplings in the North- 

 West Himalayas. 



We have yet much to learn about the members and life histories of 

 this family. 



Fam. II. Siricidae or Urooeridse— Wood- Wasps. 



Large Insects of bright conspicuous colours ; the female is provided 

 with an elongate cylindrical boring instrument at the extremity of the 

 body. Antennae are filiform and elongate ; the abdomen has eight 

 dorsal plates, and the tibia of the front leg is provided with a spur ; the 

 anal lobe of the posterior wing is large. The larvse live in wood, in 



wh'ch they gnaw long winding 



passages ; they are blind yel- 

 lowish-white grubs, with three 

 pairs of short thoracic legs 

 but have no abdominal legs. 

 The pupa (see fig. 37, d) is 

 naked — that is, it is not en- 

 closed in any cocoon. 



Until recently our Indian 

 Stridden were little known. 

 The life-history of a magnifi- 

 cent species of Sirex, Sirex 

 imperialism not unlike the well- 

 known and oft-quoted Sirex 

 gig as of Europe, has been re- 

 cently partially worked out by 

 the writer and will be de- 

 scribed shortly here.* 

 -Stre.v impertam a, larva ; a, pupa, 9 : . 



c t imago, $. (N -W. Himalayas.) Sirex imperialis is a large 

 handsome insect, the general colouring of the male being a deep metallic 



* For a fuller account sec { Departmental Notes on Insects that affert forestry'' , 

 No. 2, p. 151, and plate VII. 



Ftq. 37. 



