128 BULLETIN 190, UNITED STATES NATIONAL MUSEUM 



sides. Thorax black, a narrow yellow line at the sides, yellow at the wing 

 base and beneath ; metathorax with grizzly tufts at the sides and a trans- 

 verse yellow line. Abdomen black and all segments except 1 and 3 

 bordered with bright yellow above and beneath; anal tuft short, semi- 

 circular, black above, yellow beneath. Coxae of forelegs bright yellow ; 

 posterior tibiae rough, bright yellow, black at lower spurs ; tarsi smooth, 

 black above, touched with yellow beneath. Forewing transparent ; costa 

 and narrowly bordered outer and inner margins lustrous blue-black ; veins 

 and discal mark black. Hindwings transparent, narrowly margined with 

 black, touched with yellow on costa. Both wings beneath yellowish at bases. 



Female. — More robust than male. Antennae simple, black. Abdominal 

 segments more broadly banded with bright yellow, 4, 5, and 6 nearly all 

 yellow; anal tuft short, blunt, yellow, mixed with a little black. 



Expanse : Male 26 to 28 mm., female 26 to 32 mm. 



Distribution. — California, Oregon, Washington, Idaho, Montana. 



Type. — Male. In the American Museum of Natural History. 



Remarks. — This species is charged with serious injury to pine and to 

 redwood {Sequoia sempervirens ) . However, we have failed to hiid evi- 

 dence that redwood is attacked. Favorites among many pines on the Pacific 

 cost and northwestern Rockies are Pinus ponderosa, contorfa, radiata, and 

 lambertiana. The moths have an extended season, emerging from March 

 to September, but principally during June. Indications of the presence of 

 larvae are resinous nodules, small and soft at first, but growing in size 

 and becoming firmer in substance on exposure. In their moist tunnels in 

 the cambium and solid wood the larvae can move unmolested. Removed 

 and exposed to air they do not survive. For purposes of rearing, pupae 

 serve best. These are found in silk-lined chambers within the growing 

 nodules, the exits well concealed under thin covers of the harder crust. 

 Collecting calls for utmost caution, as a slight prick or direct contact with 

 the gum is fatal. Even at best the percentage of moths emerging from 

 collections of pupae is frequently disappointing. The life cycle, not defi- 

 nitely known, most likely covers two years. Only well-set seasoned 

 nodules appear to be suitable for pupation. Young trees are stunted in 

 growth or killed ; large trees may be scarred badly, but not injured 

 seriously. 



Heavy infestations have been reported by F. X. Williams on Monterey 

 pine at Carmel, Monterey County, Calif. At Walpole, on the coastal 

 border of Oregon and Washington, B. G. Thompson and I collected 60 

 or more pupae on Pinus contorfa after hard, grimy work, when one of 

 those cold, wet coastal fogs drove us to seek shelter in a cabin. The box 

 of pupae was placed on the stove and forgotten when a fire was lighted. 

 When next examined, the pupae were baked hard. Long series of reared 

 examples in the United States National Museum have been supplied by the 

 Bureau of Entomology and Plant Quarantine from American River, 



