THE GENUS DENDEOCTONUS. 75 
burning of the infested bark during the principal period of larval 
development and during the inactive or overwintering periods, if such 
are found within its range. 
This species has not been recognized within the United States, but 
it is not improbable that it may be found in the pine forests of south- 
ern Arizona and New Mexico. 
The writer has identified thirty-six specimens received from Prof. 
A. L. Herrera and Dr. S. J. Bonansea, collected from pine in Ame- 
cameca, Michoacan, and Tacubaya, Mexico. 
BIBLIOGRAPHY. 
Hopkins, 1906c, p. 80; Hopkins, 1909, pp. 97-99. 
No. 7. THE LARGER MEXICAN PINE BEETLE. 
(Dendroctonus parallelocottis Chap. Figs. 37-39.) 
The larger Mexican pine beetle is a somewhat elongate, cylin- 
drical, dark brown to black barkbeetle, 5 to 6 mm. in length, with 
broad, deeply grooved head; broad prothorax, with sides nearly 
parallel and but slightly narrowed toward the head, and elytra with 
dense, moderately coarse rugosities, the declivity with coarse punc- 
tures and long erect hairs. (See fig. 37.) It attacks living pine 
trees in Mexico, excavating coarse, slightly winding, longitudinal 
or oblique and sometimes branched egg galleries (fig. 38) through 
the inner bark. The larval mines are evidently concealed beneath the 
inner layers of bark, and the larvse evidently transform to pupae in 
separate cells in the outer bark. It is usually associated with the 
smaller Mexican pine beetle in the same tree. 
Very little appears to be known in regard to the seasonal history 
of this species, but it is so closely related to the Colorado pine beetle 
in general characters that it is probably quite similar in seasonal 
history as well as in habits and in the character of injury to the 
trees, except in such minor differences as may be brought about by 
its more southern range. It is evident that the unhealthy and dying 
condition of the pine in certain localities in Mexico, which has been 
reported from time to time, is caused largely by this species and by 
the smaller Mexican pine beetle. 
Ten specimens of the beetle and one of the galleries, received from 
Prof. A. L. Herrera, collected in Michoacan, etc., have been examined 
and identified by the writer. 
If this species is found overlapping the range of the Colorado pine 
beetle, it can be distinguished from that species by the slightly 
longer prothorax, with sides more parallel and less narrowed toward 
the head. 
BIBLIOGRAPHY. 
Hopkins, 1906, pp. 80-81; Hopkins, 1909, pp. 99-101. 
