THE GENUS DENDROCTONUS. 



103 



collection when examined by the writer on January 12, 1900. The 

 reference in the original description to the front of the head " coarsely 

 granulated, channeled" applies to the type, and at once distinguishes 

 it from the other two specimens which are without a median frontal 

 channel or groove. The " strong transverse impression about one- 

 fourth from the an- 

 terior margin" of \ l"sN^ I )M I j / 

 the prothorax is as- r\V //< I () 

 sociated with the 

 more distinct trans- 

 verse elevation 

 which the author 

 Failed to mention. 

 In the writer's re- 

 marks (Hopkins, 

 1905, p. 81) under 

 D. parallelocollis it 

 is stated that D. 

 parallelocollis Chap . 

 and D. approxima- 

 tus Dietz are evi- 

 dently the same, 

 but further com- 

 parative studies 

 have convinced 

 him that they are 

 specifically distinct. 



Pupa. In addi- 

 tion to the generic, 

 divisional, and sub- 

 divisional charac- 

 ters, the apex of the 

 front and middle 

 femora have each a 

 minute subapical 

 s p in e ; abdominal 

 tergites 1 to 6 with 

 small pleural spines, 

 1 without distinct 

 dorsal and lateral spines; 2 to 6 with distinct dorsal and lateral 

 spines, increasing in length and prominence to and including tergite 

 6; 7 and 8 smooth; 9 with long pleural spine. Pupal type labeled 

 "Hopk. U. S. No. 5777." 



Larva. In addition to generic and divisional characters, the front 

 has a broad, but not prominent, median elevation; clypeus short, 

 broad, with apex truncate; pro thoracic segments with prominent 



FIG. 64. Dendroctonus approximates: Egg galleries. (Original.) 



