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. 
