NO. 2130. XORTH AMERICA RHAPHIDOPHORINAE—CAUDELL. 679 



PHRIXOCNEMIS OBESUS, new species. 



Description. — (Male, the female unknown.) Form robust; color 

 shining dark brown above, merging into yellowish brown below. Head 

 large and broad, the interocular space twice as broad as one of the 

 eyes; palpi with the fifth segment a little longer than the thu'd. Pro- 

 notum slightly broader than long, very broadly rounded above, the 

 anterior margin very slightly and broadly concave, the posterior 

 margin truncate, the lateral lobes with the lower margins nearly 

 straight, the angles evenly rounded; meso- and metanotum together 

 about as long as the pronotum and with the lateral lobes descending 

 about the same distance as those of the pronotum, the lower margins 

 broadly rounded. Abdomen smooth, broad anteriorly and narrow- 

 ing gradually posteriorly; subgenital plate divided for nearly or 

 quite its entire length; cerci medium in length and bearing numerous 

 very fine long hairs. Anterior femora unarmed on the outer inferior 

 margin, the inner margin armed for nearly the entire length with 

 rounded tubercucles, so densely set as to touch each other at the 

 bases, and subapically with a single short movable spine; middle 

 femora armed beneath on both margins with two or three short stout 

 movable spines and several small triangular teeth; hind femora stout, 

 about two and one-half times as long as the greatest width, armed on 

 both ventral margins with acute teeth, above furnished with a few 

 small acute granules; fore tibiae unarmed above, beneath armed with 

 four moderately long stout movable spurs on each margin, the apical 

 one the longest, and with one apical lateral spur on each side; median 

 tibiae armed hke the anterior ones and in addition have a single spur 

 above at the apical third on the anterior side and two on the posterior 

 side, one not quite opposite the one on the other side and one at about 

 the basal third; posterior tibiae straight, with three or four acute 

 triangular teeth between the dorsal spurs, which are about as long 

 as the tibial depths, the apical one separated from the preceding by a 

 distance a little greater than the length of one of them ; apical calcars 

 long, the outer ventral one but little less in general bulk than the 

 median one, the upper one a third longer than the median one, being 

 apparently one-third or more longer than the tibial depth, by actual 

 measurement fully twice as long; beneath the hind tibiae are armed 

 with a single preapical spur, situated mesially and of moderate size. 



Length, pronotum, 6 mm.; fore femora, 6 mm.; hind femora, 12 

 mm.; width, hind femora at broadest point, 4.5 mm. 



Hoiotype. — Alameda County, California. In the United States 

 National Museum, Cat. No. 19462. 



This specimen was determined by Scudder as Ceuthophitus cali- 

 fornianus. It is apparently somewhat allied to serrata Rehn, but 

 certain characters, especially the armature of the fore femora, seem 



