14 PROCEEDINGS OF THE NATIONAL MUSEUM vol.72 



distinct in defectivus as in GenarcJies (as represented by facialis 

 [Gravenhorst] ) , which he placed in the Mesoleiina. In fact, Hvmer- 

 tus and Genarclies are very doubtfully distinct generically, the pres- 

 ence of the alar areolet in Genarches and its absence in Hitnertus 

 being the only apparent character for separating them. I fail to 

 find on the only specimen of Genarches available to me the tooth de- 

 scribed by Foerster as being located near the apex of the third joint 

 of the maxillary palpus. Both Himertus and Genarches belong, in 

 my opinion, in the Mesoleiina where they are closely related to 

 Protarchoides Cushman. 



The following key will separate the four North American species 

 here referred to Himertus. 



1. Black species 2 



Rufous or ferruginous species rubiginousus (Oresson). 



2. Clypeus with a sliarp tooth at junction of basal and apical 



areas ater (Cushman) . 



Clypeus without such a tooth 3 



3. Front and middle tarsi "reddish brown" flavidus (Davis). 



Front and middle tarsi yellow dakota, new species. 



HIMERTUS ATER (Cushman) (new combination) 



Neoprotarchus ater Cushman, Proc. U. S. Nat. Mus., vol. 64, art. 20, 

 1924, p. 10, fig. 4. 



The type is female, not male as stated in the original description. 



HIMERTUS FLAVIDUS (Davis) (new combination) 



Clepsiporthus flavidus Davis, Trans. Amer. Ent. Soc., vol. 24, 1897, p. 326. 



Apparently very closely allied to dakota and perhaps identical 

 with it. 



HIMERTUS DAKOTA, new species 



Fetnale. — Length 12 mm. ; antennae 10 mm. 



Structurally practically identical with ater (Cushman) except that 

 the clypeal tooth is lacking, the malar space is slightly longer, the 

 longitudinal groove of propodeum and first tergite are much less 

 distinct, the inner hind calcarium is barely half as long as basitar- 

 sus, and the postnervulus is broken distinctly above the middle. 



In color the same as ater except as follows: Facial spot divided 

 medially and flanked on either side by a reddish spot; all tarsal joints 

 except apical, front tibia entirely, middle tibia except reddish apex, 

 and somewhat more than basal half of hind tibia pale yellow ; hind 

 tarsus somewhat fuscous at base. 



Type locality. — Spearfish, South Dakota. 



Typc—Q.^t. No. 40443, U.S.N.M. 



One female taken July 26, 1924. 



