THE GENUS DENDROCTONUS. 163 
or, in other words, the stumps of trees felled in the fall and winter 
should not be barked to destroy the broods of this beetle before June 
or July, but the barking must be completed before the following 
March. Trees felled during the spring and summer to serve as traps 
should not have the bark removed for at least two months after the 
trees are felled. 
In some sections of the country this beetle appears to be attracted 
to the trunks of felled trees much more than to those of others, 
depending probably more on the species of tree and local conditions 
relating especially to the presence or absence of certain other insects 
which would or would not interfere with the development of their 
broods. 
In the vicinity of Monterey, Cal., it was found by the writer abun- 
dant in September in the bark of trees felled by storm the previous 
April. This suggested the utilizing of trap trees in such localities 
to attract the beetles to the bark of the trunks, as well as to that on 
the stumps. 
BASIS OF INFORMATION. 
The above statements are based on investigations by the writer 
in many localities in different sections of West Virginia in 1890 to 
1894; at McCloud and Berkeley, Cal., Grants Pass and Albany, 
Oreg., near Spokane, Wash., and at Moscow, Idaho, April to June, 
1899; in the Black Hills, South Dakota, 1901 and 1902; at Priest 
Lake, Idaho, August, 1902; at Del Monte and Monterey, Cal., Sep- 
tember, 1902; at Williams, Ariz., Septejnber, 1902; at Vermejo, 
N. Mex., May, 1903; at Flagstaff, Ariz., May, 1904; in the Yosemite 
National Park, California, June, 1904; at Brunswick and Portland, 
Me., May and June, 1900; at Maiden, Wyoming [Melrose], and Lynn 
Woods, Mass., May, 1906 (in Norway spruce defoliated by gipsy 
moth); at Milford, Pa., May, 1905; at Pink Beds, N. C, July, 1904; 
at Manitou Park and Palmer Lake, Colo., October, 1905; in Ventura 
County, Cal., June, 1904; at Garland, Colo., June, 1906; on Grand 
Island, Michigan, July, 1907; by Mr. W. F. Fiske, at Webster, N. H., 
June, 1904; at Pink Beds, N. C, May, 1905; on Grand Island, Michi- 
gan, October, 1906; at Capitan and Cloudcroft, N. Mex., March to 
May, 1907; by Mr. J. L. Webb, in the Black Hills, South Dakota, 
June to October, 1902; at Flagstaff, Ariz., June to August, 1904; in 
the vicinity of Centerville, Idaho, May to August, 1905; in the Cap- 
itan Mountains, Lincoln National Forest, and White Mountains, New 
Mexico, and in the Chiricahua National Forest, Arizona, June to 
September, 1907; by Mr. H. E. Burke, at Palo Alto, Cal., May, 1905, 
May, 1906, and September, 1906; in the Yosemite National Park and 
vicinity, at Wawona, Summerdale, Little Yosemite, and Yosemite, 
Cal., May to September, 1906; at Kamas, Panguitch, and Panguitch 
