250 Annals Entomological Society of America [Vol. Ill, 



crcnations which are cf)ntinu()us as a scries with a row of crcnations or 

 IjrojccLinj,' tubercles ahjnj,' the caudal mar^'in ; all are setij^'crous. Tuber- 

 cles all stron}i;ly developed. Carinae sub-horizontal. 



Carinal margin of the third segment rather longer than that of the 

 second but similarly sculj^tured. 



Subsequent segments becoming longer, the rows of tubercles they 

 bear more numerous, the carinal crenulations weaker, and the caudo- 

 lateral angles more rounded excepting in the last few where they tend 

 toward rectangular. In the antepenult segment alone are the caudo- 

 lateral angles a little produced. A transverse sulcus between the sec- 

 ond and third or the third and fourth rows of tubercles from the caudal 

 margin. Two longitudinal impressions, one a little each side of the 

 median, extending from ce]jhalic margin a short distance caudad and 

 then curving out laterad. Wide spaces intervening between the carinae 

 of adjacent segments. 



Anal scutum bearing transverse rows of strongly developed, coni- 

 cal setigerous tubercles like those of other segments, these rows well 

 separated from each other. Apical process of scutum decurved, coni- 

 cal, not truncate, and bearing long setae as usual. 



Anal valves with the dorsal and mesal margins sub-parallel, the 

 caudal margin meeting the mesal in a rounded but as a whole somewhat 

 acute angle. A little cephalad of the caudo-mesal angles is a transverse 

 impression crossing the median line from valve to valve. Mesal mar- 

 gins strongly elevated. A conspicuous conical and setigerous elevation 

 near the middle of each valve, this elevation closer to the mesal than 

 to the dorsal margin. 



Anal scale with each half in outline like that of shoe with high 

 instep. Caudal margin crcnately incised a little mesad of each caudo- 

 lateral angle, the crenulation adjacent to each angle bearing a long 

 .seta. 



Ventral plates pilose. The transverse impression in most more 

 strongly developed than the longitudinal. 



Legs rather long, very sparsely hirsute proximally l)ul more dense- 

 ly so distally. Second and third articles inflated dorsally. 



The first legs reduced as usual, the second intermediate in size. 



Gonopods of male of moderate size. Each one presenting two main 

 chilionous processes of which the ccphalo-mesal one is ai)ically biden- 

 tate and presents near its base an acute conical tooth projecting in a 

 cephalo-mesal direction. The second process lies against the first for 

 most of its length but distally diverges from it, extending more directly 

 ventrad and ending in an acute point. See further PI. XXXVIII, 

 fig. 6 and PI. XXXIX, fig. 1. 



Length of male IS mm. Width 1.0 mm. Length of antennae 

 2-1- mm. 



Locality — Mill Creek Canyon, Salt Lake Co., Utah. 

 (Sept., 1900). 



