OF WASHINGTON. 81 
as described in Bulletin No. 56, West Virginia Agricultural 
Experiment Station. 
Dendroctonus parallelocollis Chap. Ten specimens received 
from Prof. Herrera, taken from dying pine trees in Michoacan 
and other localities in Mexico. This is evidently the same as 
D. approximatus Dietz, which name is more recent, but may 
be used for the variety found as a common enemy of the 
pine in Arizona and New Mexico. Specimens of this variety 
are distinguished from those before me from Mexico only by 
the much shorter pubescence and hairs on the sides of the 
pro thorax towards and on the basal angle. All the species 
of Dendroctonus are exceedingly variable, and when a large 
series of specimens of -allied forms are examined it is very 
difficult to separate them by any constant characters. 
Dendroctonus valens Lee. Four specimens, Michoacan, Mexico 
in pine, received from Prof. Herrera. These are typical ex- 
amples of the large red Dendroctonus heretofore identified as 
D. terebrans Oliv., which latter is a black form restricted to 
the Eastern and Southern United States, while D. valens is 
widely distributed over the Eastern as well as the Western 
United States and is a common enemy of all of the pines, 
and occasionally found in spruce. It breeds in the living 
bark at the base of healthy trees or that of stumps of 
recently felled ones. I have found that a large per cent, of 
the so-called basal fire wounds of the Western yellow pine is 
primarily due to the work of this species. Very little evidence 
has been found, however, of trees having been killed by it. 
Hylurgops planirostris Chap. One specimen, Mexico City, 
1903, in firewood, received from Prof. Herrera, under his 
number 865. This species was recorded by Blandford from 
several localities in Mexico and Guatemala. It is, as he says, 
allied to H. rugipennis Mann., which I have found to be common 
in Picea, Pinus and occasionally in Abies and Pseudotsuga 
from Northwestern Washington to the Black Hills of South 
Dakota, and south to Monterey, California and Williams, 
Arizona. The Mexican species is easily separated from 
rugipennis, however, by the obscure punctures and fine rugo- 
sities of the pro thorax. Blandford included H. planirostris in 
the genus Hylastes, but it seems to me that Hylurgops is 
sufficiently characterized by the deeply bilobed third tarsal 
joint and ether characters to justify retaining it for this and 
several European and American species. 
Mr. Schwarz stated that the life-history of the remarkable 
Mexican Scolytid genus Oiapuisia has been published by 
