MORGAN HEBARD I 79 



however, decided color variation occurs and occasionally size varia- 

 tion makes it necessary to examine material carefully before def- 

 initely correct determinations can be given for females. The 

 two other North American species of the genus, aiistralasiae and 

 Jidiginosa, show distinctive features, not only of structure, but of 

 coloration as well. 



Characters of Male. — (Yuma, Arizona.) Size large, form stout. Head elongate;-^" 

 interocular space narrow, less than one millimeter in width, interocellar area form- 

 ing an obtuse angle with ocellar areas; ocelli pale and distinct. Pronotum weakly 

 convex, the convexity more decided narrowly laterad, disk with broad but shallow 

 oblique sulci; margin above head transverse, thence lateral margins are divergent 

 and weakly convex to slightly beyond mesal point, thence weakly convergent and 

 convex to caudal angles, caudal margin broadly convex; all angles very broadly 

 rounded. Tegmina and wings elongate and fully developed. Dorsal surface of 

 abdomen unspecialized, with latero-caudal angles not produced and bluntly rounded. 

 Supra-anal plate entirely subchitinous, represented by a hyaline mantle which 

 extends for half its length beyond the subgenital plate, lateral margins weakly con- 

 vergent and weakly convex to an acute angulate median emargination, which ex- 

 tends about one-third the distance to the base of the plate, apices of extremities 

 thus formed rounded. Styles very elongate and tapering to very slender apices. 

 Sinistrad within the anal chamber, an elongate, stout, chitinous arm extends cau- 

 dad, with apex acute and curved dorsad and bearing on its distal face a minute, 

 narrow, subchitinous flange; dorsad, just before the distal extremity, another short, 

 acute projection occurs, directed distad. Above this arm a partially chitinous 

 projection, of equal length, is directed dextrad, with swollen, transverse, chitinous 

 apex giving it the form of a rounded T. Dextrad within the anal chamber, ceph- 

 alad of a rounded, chitinous lobe, project dorsad two processes, directed sinistrad, 

 which are connected at their bases, these taper evenly to their aciculate apices, 

 with dorsal margin of dorsal process sharply serrate. At the base of this organ and 

 hidden by the lobe, are very complex, convolute, soft processes with a slender, 

 curved, chitinous process wound about their base. Subgenital plate small, trans- 

 verse, free margin moderately convex to style sockets, between these broadly trans- 

 verse; styles symmetrical, very elongate, slender, cylindrical processes, over twice 

 the length of the subgenital plate. Limbs elongate and slender. 



Characters of Female. — (Decatur, Alabama.) .Agrees with male except in the 

 following features. Form stouter. Head and [jrunotum in consequence propor- 

 tionately broader, interocular space nearK two millinu'ters wide. Ocellar area 

 not as strongly defined, but ocelli eciualh^ distinct. Pronotum much more evenly 

 con\ex, with discal sulci subobsolete. Tegmina and wings le.ss elongate, extend- 

 ing to apices of cerci. Sui)ra-anal plate weakly tectate, entirely chitinous, lateral 



-'" The head is found to be decidedly shorter in some individuals, in such being much 

 nearer the normal t>pe found in P. brnnnea. 



MEM. .\M. ENT. SOC, 2. 



