106 



The single male has the front convex, closely, rather finely granulate- 

 punctate, with a fine, median, vertical carina; the elytral interspaces are 

 less closely punctured than in the female, with a few coarse hairs behind; 

 and the declivity is more coarsely toothed than in hopkinsi. 



Pityogenes hopkinsi Sw.; Syr. Univ. Col. For., Tech. Pub. No. 2, 8-10, 1915; 

 Blackman, Syr. Univ. Col. For., Tech. Publ. No. 2, 11-66, plates 1-6 (Life 

 history and habits.) 



Length, 2 mm.; black, with the elytra reddish-brown on the caudal 

 two-thirds, legs and antennae piceous; the female front with a deep sub- 

 circular impression, the declivity retuse with the sutural striae rather deeply, 

 widely impressed and shining, with a row of three, small, widely separated 

 teeth on the declivital prominence of each elytron; the male with the front 

 convex, coarsely granulate and closely hairy, without the median impression, 

 the declivity strongly retuse, with the three teeth on each side coarse, the 1st 

 compressed, curved, acute behind, the 2nd and 3rd conical and acute. 



Host trees.' — White Pine, Red Pine, Jack Pine, White Spruce, 



Distribution. — Eastern Canada and Eastern United States. 



The most abundant bark-beetle in limbs of eastern pines. Usually 

 in collections under sparsus Lee; see Pityokteines sparsus Lee. 



Pityogenes lecontei Sw.; Syr. Univ. Col. For. Tech. Pub. No. 2, 10, 1915. 



Length, 2 mm. Very closely allied to hopkinsi, but readily distin- 

 guished by the different frontal pit of the female. The front of the female 

 is shining, granulate-punctate, with two elongate approximate foveae with 

 a combined outline longer than wide, situated on the median line at the 

 base of the epistoma, the foveae separated by a narrow median carina; the 

 frontal hairs sparse and fine. 



I have seen only the unique type. Probably allied to hopkinsi in 

 habits. 



Pityogenes carinulatus Lee; Am. Ent. Soc. Trans., 5: 70, 1874 (Cryphalus); 

 hamatus Lee, Am. Phil. Soc. Proc, 17: 624, 1878, carinulatus Lee, male. 



Length, 2 • 9 mm. to 3 • 5 mm. The female has the large deep excavation 

 occupying the central part of the front; the elytral declivity very steep, 

 with a row of three small teeth on each side, the 1st minute, the 2nd and 

 3rd moderate, conical-acute and incurved. The male has the front convex, 

 shining, closely granulate-punctate, with a wide, shining median space; the 

 declivity very different from the female, very broadly but not deeply 

 concave, shining, minutely punctured, acutely margined, with two teeth 

 on each side, the upper tooth very prominent, long, slender, hooked at the 

 tip, at the upper margin of the declivity, the lower tooth small, acute, near 

 the apex, preceded and followed by small serrations of the acute margin, 

 which there bears a sparse fringe of long, stiff, obliquely erect reddish hairs. 



Host trees. — Western Yellow Pine, Jeffrey Pine (Hopkins). 



Distribution. — Southern British Columbia, through the Western States 

 into California and Colorado. 



A very abundant secondary enemy to yellow pine in British Columbia. 



The species is very abundant over an extensive range, and presents 

 many variations. A race with rather distinct characters is represented in 

 our collection from Colorado. 



Pityogenes knechteli, n. sp. 



Length, 2-8 mm.; rather slender; the front granulate-punctate, convex 

 in the female with a divided median pit preceded by a reddish densely 

 pubescent area; the pronotum emarginate on the sides in front, strongly 



