236 Annals Entomological Society of America [\o\. Ill, 



First segment somewhat semi-circular or sub-rcnifonn, the anterior 

 median rcj^ion extending into broad excavation of head. Carinae 

 very weak, continuous with the finely raised line of cephalic margin. 

 The inner bristle on each side more than one-third the distance from the 

 distinct longitudinal median keel to the outer bristles. The two outer 

 bristles of each side upon carina, extending dorso-laterad and the 

 caudal one in a transverse line with the inner ones. 



Anal scutum truncate caudad, but the caudo-lateral angles extended, 

 the intervening margin widely set in. 



Anal valves equalling the scutum ; the caudal margin of each nearly 

 straight or but little curved, distinctly raised; an impressed longitudinal 

 line toward dorsal margin and a similar one toward the mesal; three 

 bristles borne a little ccphalad of the caudal margin, the uppermost 

 of these being close to the anal scutum, and the lowermost near the 

 middle line of the valve. 



Anal scale trapezoidal, the caudal margin wide, widely weakly 

 incurved; a long bristle borne near each caudo-lateral angle. 



First two pairs of legs of male slender, six-jointed as usual; the 

 claws large; without special ]3rotubcranccs, and with no roughenings 

 on the distal articles. 



Third legs stout and, like the subsequent ones, seven -jointed; the 

 ultimate joint roughened over the ventral and vcntro-lateral surfaces, 

 except proximal!}', with rows of short transparent processes; femur 

 swollen into a wide enlargement on the dorsal side. 



Fourth and fifth legs of male similar to the third but with the dor- 

 sal face of femora not bulging. 



Sixth legs of male like the fifth but the coxae bulging vcntrad. 



Seventh legs of male with coxae strongh' bulging vcntrad into 

 prominent rounded processes as shown in the figure (PI. XXXII, fig. (i). 



Anterior jmir of processes of male gono]XxJs broad plate-like struc- 

 tures with teeth along mesal portion of distal edge; jjostcrior pair 

 large, strongly inclined caudad, a secondary, somewhat flattened, 

 accessory division along proximal portion of caudo-lateral surface; 

 a conical ])rocess springing from the base of each (see PI. XXXI, figs. 

 4, 5, and 0.) 



Eighth legs or accessory gonopods with tlie distal article strongly 

 enlarged as usual, the basal article more than commonly elongate, and 

 extended ventro-mcsad into a conical i)rocess which bears distad a 

 numlKT of very long bristles; below the conical process the proximal joint 

 is shallowly excavated for the reception of a rounded protuberance 

 of the posterior gonopod of the corresponding .side. 



Length '2.'> mm.; width 2.9 mm. 



Locality — City Creek, Mill Creek, Provo and other canyons 

 of the Wahsatch Mountains, Utah. 



