94 NORTH AMERICAN BLATTIDAE 



in form showing some homology to that of P. americana, but con- 

 siderably more specialized. 



This species and P. caudelli are the only ones of the pale forms 

 of the genus which, in the females, have complete tegmina and 

 wings. Those of the present species are much larger and more 

 robust than those of caudelli, and have the tegmina and wings 

 decidedly shorter, the former with apices falling distinctly short 

 of the apex of the abdomen. In the females of caudelli these organs 

 have retained the full power of flight, in those of the present species 

 sustained flight would be impossible. 



Characters of Male— {Type. Huachuca Mountains, /Vrizona.) Size rather large, 

 form slender. Head much as in caudelli, rather evenly rounded, with ocelli well 

 defined, but margins of ocellar areas rounding rather weakly into the inter-ocellar- 

 ocular area, which area is feebly flattened, weakly convex, showing a few micro- 

 scopic punctae. Interocular space narrower than that between antennal sockets, 

 slightly wider than that between ocelli. Pronotum unusually long for the genus, 

 with greatest width distinctly caudad of mesal point and with cephalic angles dis- 

 tinctly more broadly rounded than caudal angles, oblique sulci of disk subobsolete.i" 

 Tegmina and wings normal, fully developed; the former and anterior field of the 

 latter proportionately narrower than in the other species of the genus; wings (in 

 the small series) with three to four incomplete and four to five complete rami of 

 the ulnar vein. Median segment supplied mesad with two subtriangular, rounded 

 but decided, elevations, with cephalic face of each furnished with a ^-er\■ hea\->- 

 tuft of hairs, the surface of the segment is also supplied cephalad of these with a 

 very few scattered hairs. First dorsal abdominal segment similarly specialized in 

 every way, except that the elevations are not as broad and the scattered hairs ceph- 

 alad are even less numerous. Sixth dorsal abdominal segment with distal margin 

 nearly straight, trans\erse. Supra-anal plate with lateral margins proximad 

 weakly con\-ex and nearly transverse to between the cerci, there con\-ex-con\ergent 

 to the rather broadly rounded apex, the small produced portion with margins thus 

 forming an obtuse angle with those of basal portion; proximal portion transverse 

 and narrow, with surface feebly convex above cerci and feebly concave in inter- 

 vening area, small produced portion strongly deflexed, with surface concave and 

 strongly declivent distad, thus forming, at the juncture with the proximal portion, 

 a well-defined, rounded and weakly convex, transverse ridge. Cerci elongate and 

 slender, with lateral margins crenate distad. Genital hook showing little narrow- 

 ing at point of recur\ature, and with recurved portion stout and of subequal width 

 throughout. Chitinous, aciculate tip of adjacent process more elongate than usual 

 and weakl>- curxed dextrad onl>' toward apex. Subgenital plate moderately con- 

 vex, except toward bases of styles, where a slight concavit}^ is indicated; lateral 

 margins moderately con\-ex and feebly con\ergent in proximal half, then mod- 



'■" In the series before us rarel>- moderatch- pronounced. 



