m.3.] LE CONTE OX EOCKY MOUNTAIN COLEOPTEEA. 507 



Xyloterus bivittatus. G. 

 Tomicus plastograplius. V. P., 9,400. 

 Tomicns rectus. V. P., 9,400. 

 Tomicus latidens, $ . V. P., 9,400. 

 Scolyttis unispinosns. V. P., 9,200. 

 Dendroctonus terebrans, formvalidus. 

 Dendroctouus similis var. ?. G. 

 Hylesiuus sericeus. G. 



Phloeotribuspuberulus, n. sp. 520. V. P. 



9,400. 

 Phloeosinus serratus ? or n. sp. G. 

 Hylastus longu3. G., V. P., 9,400. 

 Hylurgops rugipeunis. V. P., 9,400. 

 Allandrus bifasciatus. G. 

 Bracliytarsus alternatus. L. V. 

 Apion, 3sp. G.,L. V.,Y. P. 



III.— DESCEIPTIONS OF KEW SPECIES. 



CiciNDELA wiLLiSTONi. — Of tlie usual dull bronzed brown above, 

 with green and bluish reflexions in the impressions of the prothorax, 

 not shining ; beneath metallic blue and green, clothed with erect coarse 

 white hair, except at the middle of the ventral segments. Labrum white, 

 with narrow black margin, transverse, sinuate in front, with an acute 

 tooth at the middle; base of mandibles white; labial palx)i testaceous, 

 last joint black. Head as rough as in the allied species, longitudinally 

 rugose near the eyes, and more finely upon the front, which is blue and 

 green, and not hairy. Prothorax as rugose as in G. formosa; sides 

 slightly rounded only in front, not or scarcely narrowed behind ; base 

 less cylindrical than in the allied species; impressions deep, sides with 

 coarse erect white hair. Elytra rather strongly punctured, with a broad 

 lobed white margin and refracted wide white band, the descending por- 

 tion of which is long, and hooked very near to the terminal lunule; 

 humeral lunule not at all oblique; bead of side margin dark metalhc; 

 apex rounded and alike in both sexes, scarcely perceptibly serrate; 

 sutural spine small. Length, 10.5-14"". 



Lake Como, Wyoming Territory ; found in abundance on alkaline 

 mud by Mr. S. W. Williston, of Yale College Scientific Expedition. 



3 Prothorax very shghtly narrower behind the middle; sides of elytra 

 not dilated ; left mandible slightly and very obtusely angulated on the 

 outer edge, near the tip. 



$ Prothorax flatter and wider at the base than in the (? ; sides of elytra 

 distinctly though but slightly dilated just in front of the middle; mandi- 

 bles alike, not angulated near the tip, but regularly rounded. 



This might be readily taken for a race of formosa, latesignata, or 

 fulgida, with which it agrees in having the outer edge of the mandibles^ 

 acute, as well as in general characters and appearance. Nevertheless 

 it differs from fulgida by less smooth and shining upper surface, and 

 from all of the three by the pattern of the markings, which do not per- 

 ceptibly vary, and by the sexual characters. It shows in the latter a 

 tendency towards repanda, MrticolUs, &c., but in those species the balance 

 of specific distinctions is preserved by the mandibles being more slender, 

 much more prolonged at the tip, and destitute of the acute slightly ex- 

 planate external edge seen in the formosa group. 



DTSCHrRiTJS MONTANUS. — Elongate, brownish black,with brassy reflex- 

 ion; antennge and legs brown. Epistoma truncate, with angles promi- 

 BuU. V, 3 12 



