THE GENUS DENDBOCTONUS. 



91 



Typical female labeled "type of revision, type of drawing/' name 

 label, "Hopk. 4-18-02, 9 , II. S. 58, S. C." 



Type in Le Conte collection labeled "Type 1, D. frontalis (Fab.) 

 Zimm.," red disk (= Carolinas). 



Male type: Length, 3.5 mm. Front with prominent frontal 

 tubercle each side of a broad, deep frontal groove. Pronotum 

 without transverse elevation or impression across the anterior area. 

 Elytral declivity with striae more impressed and the interspacial 

 granules coarser and more sparse than in the female. 



FIG. 51. Dendroctonus frontalis: Egg galleries and larval mines, a, Entrance; b, entrance burrow; c, egg 

 gallery; d, normal larval mine; e, abnormal larval mine;/, terminal; g; ventilating burrows. (Original.) 



Typical male labeled with name, "Hopk. 1-16-08, ,U.S.N.M. 

 37, sp., N. C." 



Variations. The length varies from 2.5 to 4 mm., with the average 

 at about 3.2 mm. The color ranges from light brown to nearly black; 

 the epistoma, front, prothoracic punctures, and elytral rugosities vary 

 as usual. The anterior area of the pronotum, which is glabrous in 

 the typical females and males, usually has a few long hairs. 



Distinctive characters. This species is distinguished from D. ari- 

 zonicus, its nearest ally, by its smaller size, broader pronotum, with 

 finer punctures, and finer and less acute rugosities of the elytra. 



Eevisional notes. The type series in the Le Conte collection is repre- 

 sented by three specimens one labeled "Type 1, D. frontalis (Fab.) 



