FAMILY SCOLYTIDAE 511 



Beetle. $ Oblong cylindrical, black, moderately shining ; two brilliant, prominent, 

 reddish-golden brushes of hair on the front of the head ; base of thorax with at times a 



reddish tinge ; the elytra black or very dark brown with a 

 Description. yellowish tinge, their bases often black, the black portion often 



triangular in shape ; the upper surface is more or less covered with 



small, stiff, white hairs, densest laterally. Head small, black, partially covered in front 

 by two curved brushes of long, stiff, reddish-golden hairs (pi. xlviii, fig. i <:), which take 

 off from the anterior edge of head and occupy all the area between the inner upper edges of 

 the eyes except a narrow channel medianly. These long brushes of hair curve towards one 

 another medianly (the tufts on the two sides remaining apart) to about halfway down the front 

 of the head, and then continue down it in two thin strands ; a few separate hairs start from 

 the inner surface of the eye and converge to meet the strands near their upper ends. The 

 position and configuration of these brushes of hair serve easily to distinguish the insect. 

 There is a brush of yellow hairs at the mouth, and the antennae are yellow and terminate in 

 a solid club. The thorax is one-third as long as broad, and is sharply constricted at about 

 the basal fourth, the outer angles being constricted and rounded ; a median shining 

 longitudinal line down central portion ; the surface is finely pitted, but the pits are not placed 

 closely together ; the lateral margin set with a fringe of rough hairs. The elytra are finely 

 striate, the intervals between the longitudinal striations filled with fine, close granulations 

 which become larger and wider apart in apical fourth. Under-surface black, moderately 

 shining, and set with small rough projections and with sparse, stiff, yellow hairs. Legs 

 yellow, with scattered yellow hair; tibiae of front legs brownish black. Length, 3. 12 mm. 

 to 3.4 mm. 



$ Differs from female in its smaller size, in the absence of the remarkable reddish-golden 

 brushes of hair on the front of the head, their place being taken by a few sparse yellow hairs, 

 and in the presence of two small tubercles on the head, placed transversely. The hairs on the 

 upper surface are also denser. Length, 2.6 mm. to 2.8mm. Figs. I b and le show dorsal 

 and side views of the female and male beetles. 



Egg. -The egg is small, white, round, and translucent. 



Larva. A small, curved, white maggot with a yellow head and no legs. It is shown in 

 pi. xlviii, fig. i. 



The life history of this insect was studied during two visits paid to the 



chilgoza forests of North Zhob and the Takht-i-Suliinan 



Life History. Mountains in June and November 1905. The beetle 



appears on the wing in the spring, probably at the 



beginning of May, and lays the eggs of the first generation of thr ye'ar. 

 From a large number of infested trees examined in June, the following four 

 .are taken as showing the position of this and the second genrrat ion in 

 the trees in the middle of June : 



Tree I. Mature larvae, pupae, and full}' formed but immature light 

 yellow beetles, with their outer parts still quite soft. Also one or two 

 fully mature beetles and a few dead ones at the top of the egg-galleries 

 in the tree. 



Tree 2. Fully mature males and females boring into a standing green 

 tree or grooving out pairing-chambers and egg-galleries in the bast and sap- 

 wood. Eggs laid in the lower part of the egg-gallery, but no grubs \ vt 

 developed. 



