THE GENUS DENDROCTONUS. 165 



Oreg.; Coeur d'Alene, Idaho; Duluth, Minn. ; Marquette, Mich. ; Cam- 

 bridge, Mass.; Chalco, Chihuahua, Mexico City, Michoacan, Ponada, 

 and Satazin, Mexico. It is represented in the forest-insect collec- 

 tions of the West Virginia Agricultural Experiment Station and of 

 the Bureau of Entomology by more than 5,000 specimens. 



While specimens from all over the country are included under one 

 name, it is believed by the writer that there are a number of more or 

 less distinct so-called races and varieties, and possibly- some forms 

 are specifically distinct, but, owing to the great variation in all deter- 

 mined characters which can be used for such a separation, it is thought 

 best to leave all of them under one name. The species is easily 

 separated from the southern turpentine beetle by its light to dark red 

 color, except when compared with the immature reddish specimens, 

 and then the coarser punctures on the prothorax and coarser teeth of 

 the tibia of the latter will serve to indicate the difference. 



BIBLIOGRAPHY. 



Harris, 1841 (under Dendroctonus terebrans), p. 72; Harris, 1842 (under D. terebrans), 

 pp. 72-73; Harris, 1852 (under D. terebrans), p. 76; Harris, 1862 (under D. terebrans), 

 p. 86; Harris, 1863 (under D. terebrans), pp. 84-86; Thomas, 1876 (under D. terebrans), 

 p. 146; Smith, 1897 (under Hylurgus terebrans), p. 52; Packard, 1887 (under D. tere- 

 brans), pp. 175 and 243; Packard, 1890 (under D. terebrans), p. 721; Hopkins, 1892a, 

 (under D. terebrans), pp. 64-65; Hopkins, 1899a (under D. terebrans), pp. 392-393, 

 415-421, 447; Hopkins, 18996 (under D. terebrans), pp. 14-15; Hopkins, 19026, p. 12; 

 Hopkins, 1903a, p. 61; Felt, 1903 (under D. terebrans), pp. 480-481; Hopkins, 1904, 

 p. 19; Hopkins, 1905, pp. 11, 17; Hopkins, 1906c, p. 81; Felt, 1906 (under D. tere- 

 brans), pp. 342-345, 348, 776, 792, 796; Hopkins, 1909, pp. 151-157. 



