NEVADENSIS. LAST 

 DORSAL A B D O M - 

 INAL SEGMENT OK 

 THE MALE. 



378 PROCEEDINGS OF THE NATIONAL MUSEUM. vol. xxxn. 



IDIOSTATUS NEVADENSIS Scudder. 



Cacopterk nrmulensls Scuddek, Proc. Amer. Acad. Arts Sci., XXXV, 1899, pp. 

 88, 91 (male, not female); (lat. Orth. U. S., 1900, p. 78.— Kirby, Syn. Cat. 

 Orth., II, 1906, p. 194. 



Description. — Male, female unknown. Very similar in structure 

 and appearance to C. ivqwdls. The anterior tibia? are armed as in 

 aequalis but the posterior femora are relative!}^ a little shorter. The 

 lateral lobes of the pronotum are well developed but are less sinuate 



W posteriorly than in xqualis^ being practically without 

 an}' trace of sinus. The elytra are essentially as in 

 pequalis and, like those of that species, have the outer 

 apical angles marked by a black spot. The cerci are 

 ^l?:f.'™l'f^t^^''' '^'^*^ those of cvqnalis but the structure of the last dor- 

 sal segment of the abdomen is quite diiferent, the 

 apical denticulations being short, not reaching as far 

 back as the tip of the subgenital plate, and triangu- 

 lar, not elongate, and the intervening sinus is V-shaped (fig. 63). 



Measurements.. — Length, pronotum, .5 mm.; posterior femora, 18; 

 elytra, 3. 



Type. — In the Scudder collection. 



Specimens examined. — Two males. Ruby Valley, Nevada (Ridge- 

 way). 



The female associated with these males by Scudder, but which he 

 suggested might not belong here, is really the female of /. inermis., 

 which see. 



This species is very closel}^ allied to xqualis and may eventually 

 prove to be a form of that species. The structure of the last abdominal 

 segment, however, seems to indicate quite strong!}' their distinctness. 



IDIOSTATUS SINUATA Scudder. 



Caropteris sinuaia Scudder, Proe. Amer. Acad. Arts Si'i., XXXV, 1899, pp. 88, 

 90; Cat. Orth. U. S., 1900, p. 78.— Kihby, Syn. Cat. Orth., IJ, 1906, p. 194. 



Description. — Male; female unknown. Head 'moderately deepl}' 

 inserted into the pronotum, scarcely prominent; vertex narrower than 

 in xqualis^ being scarcely more than one-fourth as broad as the inter- 

 ocular space; eyes rounded and quite prominent; basal segment of the 

 antennae broad and about as large as the vertex when viewed from in 

 front. Pronotum of medium size and moderatel}^ produced poste- 

 riorly; lateral lobes not well developed, being nearly twice as long as 

 deep, moderately declivent, posterior margin slightly sinuate; lateral 

 and median carina not indicated, the position of the former faintly 

 represented by a slight squareness of the pronotum at that point; disk 

 broadly rounded, without transverse sulci, subtruncate in front and 

 behind. Legs moderately long, the posterior femora absent in the 



