154 MISC. PUBLICATION 273, U. S. DEPT. OF AGRICULTURE 
Species Hosts and distribution 
Northorhina aspera Lee_________- Douglas fir. Western States. 
Xylotrechus undulatus Say__---_- Pines, firs. Douglas fir, hemlock, and spruce. 
Western States. 
Xylotrechus nubilus Linsley_—--~- White fir. California. 
Ulochaetes leoninus Lee____-___-__ Ponderosa pine, Douglas fir, and spruce. 
California to British Columbia. 
Aylotrechus nauticus Mann_-___~_. Oak, madrona, and eucalyptus. California 
and Oregon. 
Neoclytus conjunctus Lee____----~- Oak, ash, and madrofia. Western States. 
Neoclytus caprea Say-_---_--__-~- Oak and mesquite. Arizona, Colorado, and 
Utah. 
Brothylus gemmulatus Lee______- Oak. Colorado and California. 
Synaphoeta guexi Lee___________- Oak, maple, and willow. Pacific coast. 
Rosalia funebris Mots__---____--- Ash, California laurel, willow and alder. 
New Mexico and California to Alaska. 
Necydalis cavipennis Lec________- Alder and eucalyptus. Arizona and Califor- 
nia. 
Xylotrechus obliteratus Lec_____-. Aspen. Rocky Mountains. 
Xylotrechus insignis Lec____-_--~-- Willow. California. 
Malacopterus tenellus F________-- Willow and poplar. Arizona. 
Cyllene antennata White_____-__-. Mesquite. Southwestern States. 
WOOD-BORING WEEVILS 
(Curculionidae) 
Some of the weevils belonging to the genera Rhyncolus, Cossonus, 
Pissodes, and Cryptorhynchus are found at times working in wood. 
The work of Pzssodes has been previously mentioned (pp. 33 and 138). 
The Rhyncolus and Cossonus weevils are small brown or black 
weevils less than one-fourth inch in length, with the head produced 
into a snout. The larvae are white, legless, and comma-shaped. 
Both adults and larvae may be found boring into and destroying 
wood, but as the wood is usually in a decaying condition, they are 
seldom of any economic importance. : 
The popiar and willow borer (Cryptorhynchus lapathi L.) (57) 
bores under the bark and into the wood of poplars and willows mak- 
ing irregular more or less cylindrical tunnels which often so riddle 
the wood as to cause heavy breakage. The adults are rough, dark- 
colored weevils about one-fourth inch in length, with a band of 
bright pink across the tip of the wing covers. This is an introduced 
species which is gradually becoming widely distributed throughout 
the country. It has recently been found causing serious damage to 
willows along the Columbia River in Oregon. 
CARPENTER MOTHS 
(Cossidae) 
The larvae or caterpillars of some families of moths (Lepidoptera) 
are wood boring in habit and mine directly into the wood of injured 
or weakened trees, where they may cause additional injury which 
may result in the tree’s death. These injuries to the living tree often 
appear as serious defects when the tree is converted into lumber. 
The carpenter moths, belonging to the family Cossidae, principally 
attack broadleaved forest, shade, and fruit trees. The adults are 
large, mottled-gray moths, with spindle-shaped bodies and narrow, 
strong wings of medium to large size. They are night flyers and lay 
their eggs in bark crevices or on old wounds. The caterpillars, 
which are nearly hairless, have both true legs and abdominal pro- 
