422 WEST VIRGINIA EXPERIMENT STATlOJt 



elitra declivity which is armed on the sides with teeth of var- 

 ious sizes. 



All of our species may be readily identified by the difference 

 in size, the form of the excavation and the arrangement, num- 

 ber and size of the teeth. 



Fig. LXXXI-- Elitra declivity of species of Tomicus. 



The species which are of especial interest on account of their 

 association with the trouble caused by Dendroctonus frontalis 

 and their power of aiding this insect in its destructive work, 

 may be briefly described as follows: 



Tomicus calligraphus Germ. Length. 4.5 6.4 m m. or .17-.25 

 inch.; color, reddish to black ; declivity deeply excavated and 

 armed with six teeth on each side ; first from above very 

 small, second and third large and connected at the base ; 

 fourth and fifth medium size; sixth small, as shown in Fig. 

 LXXXI a. 



Tomicus cacographus Lee. Length, 3-4 mm or .12-. 16 inch.; 

 color, yellowish red to nearly black ; declivity deeply excavat- 

 ed and with five teeth on each side; first very small, second 

 large and connected, fourth and fifth small. 



Tomicus pini Say. 2-5. 3.5 mm. or .14 .18 inch.; color, 

 light reddish to dark reddish brown ; declivity not so deeply 

 excavated as in preceding species, and with but iour small 

 teeth on each side ; first very small, sometimes wanting in 

 female; second and third medium size closely connected; 

 fourth very small. 



Tomicus avulsus Eich. Length, 2.8 3. mm or .11 .12 inch; 

 color, yellowish to dark, reddish brown ; declivity only slightly 

 excavated and with four teeth on each side ; first, very small ; 



