FAMILY SCOLYTIDAE 



their hosts until they have become full-fed and eaten out the pupal 

 chamber, since the pupae of the flies were often found in the latter. 



They are deep metallic blue in 

 colour, with green reflexions, the head 

 and the thorax being dull coppery. The 



eyes are brilliant crimson. In the 



K * ''"'/'"? 



larger of the flies the wings have a ; y . 



transverse brown band across them 

 about half-way up. The figures show 

 these two flies. 



Niponius canalicollis, Lewis. The 

 grub of this beetle is predaceous upon 

 the grubs of the Polygraphus and the 

 Phloeosinus beetles. The insect has been 

 already described on p. 507. 



The Colydiid Beetles. The larger 

 of these is predaceous upon the Poly- 

 graphus beetle. In the galleries of 

 the Polygraphus I discovered numerous 

 smallish white eggs laid several to- 

 gether, and simply deposited on the 

 floor of the gallery. From their posi- 

 tion, and the fact that male and female 

 colydiid beetles were taken together in 

 the Polygraphus galleries, I consider 

 that these eggs are those of the larger 

 of the colydiid beetles, and are laid 



in this position to 



enable the larvae 



on hatching out 



to feed upon the 



eggs or larvae of the Polygraphus beetles. I took a 



male and female of this insect together in one of the 



egg-tunnels of the Polygraphus beetle. 



The smaller of the colydiid beetles may con- 

 fine itself to the Phloeosinus bark-borer, or may be 

 predaceous upon one of the enemies of the bark- 

 borers. 



ttt'ctlt". Light brown in colour, with a prominent he. id 

 furnished with large black eyes and short antennae; the thorax 

 is square and pitted, as also are the elytra, which leave the 



FIG, 334- 



Flies parasitic on /'. 

 North /hob. 



Fi<;. 335. 



Beetle predaceous upon l 'P of lhe 1)ll(1 . v exposed. 

 r.trcnchi. North /hob. two rohdiid beetles. 



Fig. 335 shows the larger of the 



