NORTH AMERICAN COLEOPTKRA. 299 



Male. — Last ventral with a feeble sinuation each side, a moderately deep, 

 elongate triangular impression. Antennae with Joints 2-3-4 nearly equal in 

 length, the fourth slightly broader, fifth longer and very little broader, sixth 

 shorter than second, 7-10 equal in length, but gradually broader, eleventh longer. 



Female. — Last ventral simple. Antennje with joints 2-3-4 equal in length and 

 thickness, fifth longer, sixth equal to fourth, 7-11 as in the male. 



In two specimens before nie there is a short yellow line midway 

 between the suture and side, one-fourth from apex, a third has the 

 elytra entirely black. The antennse do not show the marked sexual 

 differences observed in the vittate species, and in this respect is very 

 like albionica. While this species and albionica are closely related 

 by description, this is more convex, more coarsely punctate, without 

 aeneous lustre and less elongate. When immaculate it resembles 

 denticornis, and the sexual characters must be relied upon to separate 

 them. 



Occurs in Oregon and Washington Territory. 



9. I*, albionica Lee. — Elongate oval, narrow, depressed, piceous, surface 

 with very distinct seneous lustre. Antennse half as long as the body, slender, 

 piceous, three basal joints paler. Head moderately closely punctate. Thorax 

 not quite twice as wide as long, narrowed in front, sides arcuate, disc moderately 

 convex, the punctuation relatively coarse and densely placed. Elytra wider at 

 base than the thorax, humeri obtuse, disc subdepressed, more coarsely punctured 

 than the thorax, less dense and more shining. Body beneath piceous shining, 

 abdomen with very few punctures. Legs piceous, tibite and tarsi brown. Length 

 .06- -.08 inch.; 1.5— 2 mm. 



Male. — Last ventral not sinuate each side, a short and broad triangular im- 

 pression at the apical margin Antennae with joints 2-3 equal, fourth a little 

 longer, fifth a little longer and stouter, sixth equal to fourth, 7-10 equal, gradu- 

 ally broader, eleventh longer. Plate VI, fig. 22. 



Female. — Last ventral simple. Antennae with fifth joint a little longer than 

 fourth or sixth, otherwise as in the male. 



This species and pusilla are the smallest in our fauna, their form 

 narrowest and most depressed. They are closely allied and separable 

 with certainty by the sexual characters alone. 



In Mr. Ulke's cabinet is a green-blue specimen from Colorado 

 which is possibly a distinct species, but there are no strongly defined 

 characters to separate it from albionica, it is therefore left to the 

 future. 



10. P. raniosa Crotch. — Elongate oval, moderately convex, piceous, with 

 very faint aeneous lustre, each elytron with a sinuous yellow-wliite vitta. An- 

 tennae half as long as the body, piceous, joints 2-3 and underside of first pale. 

 Head with very few punctures between the eyes. Thorax nearly twice as wide 

 as long, narrower in front, sides arcuate, disc convex, the punctures moderately 



