78 NORTH AMERICAN BLATTIDAE 



similar, but more ample, lateral subtriangular pad-like tegmina are, 

 however, found in the females of P. desertae and P. uhleriana. 



Compared with desertae, the males are found to differ: in the 

 narrower interocular space; dark colored head, even in the palest 

 specimens; more pronounced pronotal sulci; distinctly more pro- 

 duced supra-anal plate, with free margin less truncate between 

 the cerci; shorter cerci with joints decreasing more rapidly in size 

 distad, and more nearly symmetrical subgenital'plate, the plate at 

 the dextral style not being more produced than at the sinistral 

 style, the margin between these transverse. 



The very dark females, with minute, lateral tegmina, which 

 scarcely extend beyond the caudal margin of the metanotum, could 

 only be confused with those of americana. The present species 

 averages smaller, and the females are more compact, with inter- 

 ocular space equalling that between the antennal sockets, with 

 tegmina showing hardly any traces of venation and with supra- 

 anal plate less strongly and more bluntly produced. 



Characters oj Male. — (Waco, Texas. "2) Size small for the genus, form slender. 

 Interocular space four-fifths (varying in the series to fully as wide as) interocellar 

 space. Ocelli well defined. Area between eyes and ocelli appreciably flattened to 

 a point just above the antennal sockets, with surface slightly roughened and show- 

 ing microscopic transverse folds. Maxillary palpi delicate, with third and fifth 

 (distal) joints subequal in length, each longer than fourth joint. Pronotum with 

 greatest width slightly caudad of mesal point, oblique sulci of disk very decided 

 and connected caudad by a short, transverse, arcuate impression. Tegmina and 

 wings normal, fully developed; wings (in the series) with two to five incomplete 

 and two to five complete rami of the ulnar vein. Median and dorsal abdominal 

 segments unspecialized. Supra-anal plate weakly deplanate and weakly declivent 

 distad, about twice as broad as long, free margin convex from above the cerci, but 

 with mesal portion showing some weakening of the curvature. Cerci short with nine 

 (normal) distinct joints, these decreasing rapidly in size distad. Genital hook 

 situated sinistrad, a sharply recurved chitinous process, with recurved portion 

 straight and very elongate and directed almost parallel to the basal shaft; mesad 

 and adjacent, is situated a very slender and much shorter, moderately curved, 

 aciculate, chitinous process. Subgenital plate with surface moderately convex 

 except distad, where it is weakly deplanate; lateral third of free margin, on each 

 side, nearly straight and moderately convergent, mesal third nearly straight, trans- 

 verse; at the distal angles thus formed are situated, in weakly defined sockets, sim- 

 ple slender styles, similar in size and form and in length equal to half the distance 

 between their bases. Exposed portion of eighth dorsal abdominal segment, which 



"-The "Texas" ty])e was probably taken at Dallas, or at this not distant locality. 



