OF WASHINGTON', VOLUME XIX, 1017 127 



French Entomologist being the .shape of the mandibles which, in 

 a specimen of Oistus sphenosomus Cand. in the National Museum 

 collection and determined by Mr. Champion, an- decidedly acute 

 at the tip while the mandibles of the specimens of Oistus cacicus 

 Cand. in the same collection are truncate as in the original 

 generic diagnosis. The genus includes at present, comprehending 

 the species herein described, five species. 



In a collection of miscellaneous elaterids collected by the field 

 agents of the Office of Forest' Insect Investigations and submitted 

 to me for determination by Dr. A. D. Hopkins, I found a single 

 female belonging to this genus which is described below. 



Oistus edmonstoni sp. nov. 



Elongate, subparallel, depressed, shining. Color, sanguineous brmvn 

 above; head, antennae, legs, and ventral surface almost black. Vestiture, 

 long, silky and white. Head not margined in front, flattened, slightly 

 concave and strongly punctate; mandibles acute at the tip; maxillary 

 palpi long, terminal joint, securiform; antennae moderately long and 

 slender. Prothorax broader than long, sides nearly parallel, rounded in 

 front, posterior angles divergent, lateral margins strongly swollen and 

 sulcate, anterior margin rounded over the head, with a decided median 

 emargination, posterior margin crenulate within the posterior angles; 

 proplurae densely and strongly punctate, prosternum rounded in front with 

 chin piece rugosely punctate, smooth and feeblj- punctate posteriorly. 

 Meso-metasternal suture almost obliterated; mesosternum horizontal 

 posteriorly and abruptly, perpendicularly deflexed in front. Posterior 

 coxae gradually widened inwardly. Elytra four times as long as the pro- 

 thorax, wider than pronotum, not striate but with three slightly elevated 

 ridges; very finely punctate; sides parallel to apical third and then rather 

 obliquely attenuated. Tarsi pilose beneath but not nearly so strongly 

 as in O. cacicus Cand.; tar.sal joints three and four very feebly produced 

 below, not at all lobed. Length 27 mm., width 7.-"> mm. 



TUI>C:(J. S. X. M. X<>. 21044, a female. 



Ti//>c locality: Ashland, Oregon, on cone of Douglas Fir, Sept. 

 23. 1913. 



The type was collected by Mr. W. D. Edmc-nston fof whom 

 the species is named. 



The following table will serve to separate the species now rec- 

 ( gnized : 



a. elytra metallic black or black with suture red. 



b. entirely metallic black except the legs which are brown. 



xnlnin tdll.ii- nx 



bb. prothorax red, elytra black with suture red mituralis 



aa. elytra reddish brown, yellowish or piceous. 



