I06 NORTH AMERICAN BLATTIDAE 



coloration, specialization of median segment antl form of supra- 

 anal and subgenital plates. In uhlcriana, however, the head is 

 normally more flattened between the eyes and ocelli and darkened 

 medio-longitudinally; the pronotum is proportionately shorter, 

 with point of greatest width normally mesad and the cur\atLire 

 of the cephalic and caudal angles more nearly similar, while the 

 discal sulci are more pronounced; the tegmina are distinctly 

 broader; the ridges of the median segment more decided, and the 

 subgenital plate, at the base of the dextral style, not decidedly 

 elevated. The cerci are extremely distinctive in having the inner 

 distal angles of the sixth to ninth joints acutely, though weakly, 

 produced and in consequence differing appreciably from the 

 corresponding outer angles, a feature not found constant in any 

 other known species of the genus. i*'" 



The female sex is distinctive,'" particularly in the tegmina, which 

 are lateral, but broadly and roundly subtriangular, while vestigial 

 wings are present. Confusion can consequently occur only with 

 the female of P. dcsertae, which is a more slender insect, with inter- 

 ocular space wider, tegmina decidedly narrower, w^ith sutural mar- 

 gins less convex, mesal production of sixth dorsal abdominal seg- 

 ment distinctly less broadly rounded, and distinctively shaped 

 supra-anal plate. 



The highly specialized ootheca of the present species is of an 

 entirely ditTerent type from that known for any other species of 

 the genus. 



Characters of Male. — (W'hirciiiarsh, Pennsyhania.) Size nu'diuni for the genus, 

 form moderately slender, hiterocular space two-thirds (to slightly less than^") 

 the width between the antennal sockets. "^ Ocelli well defined. Inter-ocular- 

 ocellar area appreciably flattened to a jioint just above the antennal sockets, with 

 surface microscopicalh- roughened. Maxillar\- palpi more elongate than in P. 



^^^ A production of the distal cereal joints is founil in poisylviUiirn. Though occurring 

 in both sexes of that species, it is found to be indixiduallx' e.\tr(.-nu'l\- \arial)le and ot no 

 diagnostic importance. 



1^1 The females referred by Rehn <ind ilebard in their Re\ ision to uhleriana, are here 

 properly referred to fulvesceus; at that time no differences could be found between the 

 females of these supposed geographic races. The confusion arose from the incorrect 

 placing of the female of uhleriana as that sex oi johnsoni { = Ischnoptera deropeltifonnis). 



""'- The variation in this dimension is similar to that found in virginica, see footnote 144. 



1^' In the series slightly less than, to slightly more than, the intiTocellar width. 



