I IS SECT LIFE IN INDIA AND HOW TO STUDY IT. 



129 



upon Sire® imperialis already mentioned as infesting spruce in the 



North- West Himalayas. The adult Insect appears on the wing about 



the beginning of June. The female is a 



fairly large handsome fly, black in colour 



with yellow spots upon the thorax and a 



pink spot on either side of each segment of 



the body. It is one inch in length with 



an ovipositor of one and a half inches 



(fig. 49). Dead mature Insects have been 



found in some numbers in spruce riddled 



by Sirex imperialis, the tunnels in which 



the ichneumons were found communicating 



with the Sirex ones in such a manner 



as to leave no doubt that the former Fig. 49.— Rhyssa sp. parasitic 



was parasitic upon the latter. The larval "? on . e ar,a3 , ° 



1 L Sirex imp er la Li s 



and pupal stages of the ichneumons have (N\-W. Himalayas) \» 



not yet been found. There can bo little doubt that this parasite 

 is of the greatest service in keeping down the numbers of the 

 borer. It appears to itself suffer when the wood-wasp larva has 

 gone very deep into the wood, as the ichneumon fly on becoming 

 mature has then apparently not sufficient strength to boro its way 

 out of the tree and dies in the wood after having gone a certain 

 distance.* 



Pimola punctator, Linn., is an ichneumon common in parts of 



Bengal and Assam. It 

 is a well-known para- 

 site of the silk-worm 

 moth Anthercea roylei, 

 Moore, and has also 

 been reared in the 

 Indian museum from 



several species of Sa- 

 FiG. 50.— Pimpla imnc'atov, 2 and 9, parasitic upon .., en r 



. . a . '.?. ,_ *' 1 . . T . . turnndce,a family of 



species of Saturnnda . (Reared in Indian 



museum, Calcutta.) \. moths whose cater- 



pillars are serious defoliators. The male and female are shown in fig. 50. 

 The wheat and rice weevil is parasitised by the tiny coppery-green 



* For a fuller account, vide Departmental Notes on IusectS'that affect Forestry 

 No. 2, p. 155, and plate VII, Fig. 2. 

 17 



