138 BULLETIN 63, T^NITKD STATES NATIONAL MUSEUM. 



Measurem&nts. — Male: Length, 9.5 mm., ^Yidth, 3.5 mm. Female: 

 Length, 9 mm. ; width, 3.8 mm. 



This small form would no doubt be referred to hiwieralis upon 

 superficial examination. The anterior spur of the anterior tibia? in 

 the female is comparatively stouter than in the other s[)ecies of the 

 subgenus. Such an acute observer as jNIr. lilanchard referred it to 

 "near hvmeraJis.'" Without recourse to examination of the genital 

 segments it would be very difficult to do otherAvise; the sculpturing 

 is quite like that of the latter species. 



I take great pleasure in giving the species the name of my col- 

 league. Dr. E. C. Van Dyke. 



Subgenus TRICHELEODES, new. 



Pubescent species, l)0(ly clothed with moderately long and more 

 or less erect hairs. The i)r()notum is coarsely, densely, and more or 

 less rugosely jiunctate; the huuieri are scarcely evident and rounded: 

 the scul])turing is more or less punctato-muricate, becoming muri- 

 cately tuberculate in some heterotypes. 



Sulxjeneric (jcii'dal character.'^, nude. — Apical lobe of the edeago- 

 phore triangular with a median longitudinal impression: 



Female. — (renital segment subequilaterally ti'iangular. Valvula 

 with the dorsal ])late arcuate at the external border, apical angle 

 obsolete, internal ai)ical lobe well developed. Apj^endage short mam- 

 milliform. Superior pudendal membrane reaching to the middle of 

 the dorsal plate. 



The abdomen is horizontal in the male, and in both sexes the first 

 ventral segment is about as long as the coml)ined lengths of the next 

 two, 



Belatioitt^hips-. — The species of the present subgenus in outward 

 habitus most nearly approaches Pseiideleodes, and in the liiuricately 

 tuberculate heterotypes this becomes more evident. 



The female genital characters indicate a common origin with 

 Litheleodes and Promas. In the former there is also a tendency to 

 hirsuteness (letcheri) . A vast amount of material nnist yet be care- 

 fully studied before the present question can be at all satisfactorily 

 settled. Increased eli'ort at collecting in the arid regions of the West 

 is a desideratum. 



Distrihvtion. — The species prefer the arid regions of Nevada, Utah, 

 and eastern California, one species extending northward into Oregon, 

 and also, according to Linell, into New Mexico. 



The two species of this subgenus may be separated as follows : 



Larger species more or less opaque, hairs of the elytra distinctly unequal in 

 length and slightly bristly pilosa. 



Smallei- species and Amphidora-like in facies; hairs of the elytra shorter, softer, 

 and snetjual in length Itirsuta. 



