i66 



FAMILY SCOLYTIDAE 



This Pityogenes infests also the Piniis gerardiana in the North Zhob and 

 Takht-i-Suliman forests, and also in Bashahr in the North-West Himalaya. 

 In the North Zhob and Takht forests the beetle was extremeh- plentiful in 

 1905, accompanying the Polygraphus trenchi (p. 510) and Phloeosiniis beetles 

 in their attack on the trees. Its life history in the chilgoza is very similar 

 to that in the blue pine. 



The protection and remedial measures are similar to those already 

 described for Polygraphus uiaj'or and the Tomicus beetles. 



Chalcid. — The larva of this small fly is parasitic upon the grubs of the 

 Pityogenes. 



Fly. — A brightly coloured little insect. Head black with a minute yellow pubescence 

 Eyes large, pink. Thorax and body dark metallic purple : thorax beneath is rather yellowish, 

 as are femora on inner surface ; tarsi yellow, the last joint black ; 

 tibiae black, yellowish black above. Antennae angled, black with 

 yellowish pubescence. Abdomen rounded, produced into a blunt 

 point. Wings membranous, iridescent, upper with a black stigma and a few cells. 



Parasitic and 

 Predaceous Insects. 



Life History. — I have taken this insect in the pupal chambers of the 

 little Pityogenes in blue-pine trees in Jaunsar. The tiny fly either lays her 

 eggs near the entrance-hole of the beetle or, more probably, crawls down it 

 and lays them in the pairing-chamber. The larvae feed as external parasites 

 on the scolytid grubs, which do not die before they have hollowed out 

 the pupating-chamber in the bast layer. The parasitic grub then pupates in 

 this, the scoh'tid larva dying. 



Thanasimus himalayensis, Steb. — I have fed the Thanasimiis beetles 

 with this small Pityogenes, which they devoured as 

 readily as they do the larger bark- and wood-borers 

 they prey upon (p. 508). iT^ f 



Reduviid. — This insect occurs occasionally very 

 plentifully in the galleries of the Pityogenes in blue 

 pine and more rarely in deodar, and also with Cryp- 

 tiirgus pusillus SLud Polygraphus pini in blue pine and 

 spruce. 



Young bisect. — Minute, elongate, shining ; head, thorax, and 

 first segment of body reddish yellow, rest of body with a purplish 

 metallic tinge dorsally and dark reddish underneath. Head with 

 prominent eyes and a curved scimitar-shaped proboscis ; antennae 

 yellow. 



Mature Insect. — Small, flat, elongate. lUack or greyish 

 black. Antennae inserted in front of eyes on the head, the 

 beak black, strong, and curved. Thorax triangular, narrowest 



in front. Scutellum triangular, produced into a sharp point ,"'■ 'hS^- — ^'^^^''"''"'^i 



backwards. Femora thickened. predaceous upon Pltyo- 



genes com/erae and other 



Life History. — This small bug is sometimes scolytids (magnified}. 



found in considerable numbers in the tunnels and North-West Himalaya. 



