2l6 NORTH AMERICAN BLATTIDAE 



Subfamily POLYPHAGINAE 



We follow Kirby in separating this section from the Corydiinae. 

 These two subgenera are distinctive in having the wings, when 

 present, with anal field plane, not folding fan-wise. 



The males of the Polyphaginae show the greatest ocellar de- 

 velopment and specialization found in the Blattidae, this consti- 

 tuting one of the most satisfactory single characters to separate 

 the Polyphaginae from the Corydiinae. 



In the species of the present subfamily, the sexes are exceedingly 

 dissimilar. The females of some species differ from the males in 

 all but a few generic diagnostic characters, such as the number of 

 apical spines on the tibiae. 



The following characters are considered diagnostic for the present 

 subfamily. Head of males, with ocellar areas strongly defined and 

 ocelli large, with surfaces convex; of females, greatly simplified, 

 without strongly defined ocellar areas and ocelli represented by 

 indistinct spots. Pronotum and tegmina (when present), thickly 

 covered with hairs. Tegmina of males, with venation distinct- 

 Subgenital plate of females, simple; or valvular with basal margins 

 of valves forming a deep acute-angulate emargination.^^'-' Sub- 

 genital plate of male with, or without, styles. Limbs with ventral 

 margins of femora unarmed, but very hairy; or with a single distal 

 spine on cephalic margin of cephalic femora, or, in the females of 

 some species, with a few nodiform processes meso-proximad on these 

 margins. Median and caudal femora with, or without, a dorsal 

 genicular spine. Tarsi with, or without, pulvilli and arolia. 



We have thought it best to include, in the present study of this 

 subfamily, all of the North American material before us; this 

 representing examples from localities as far south as the state of 

 Guerrero, Mexico. This material is by far the largest representa- 

 tion of the Polyphaginae ever studied, 568 specimens. All of the 

 species found in the United States should be found in Mexico, while 

 the correlation of the purely Mexican species is of great importance 

 in working out the relationship of the forms distributed north of 

 that country. 



'"This type is found in tiie Ectobiinae in Anaplecta and in the Corydiinae in IIolo- 

 compsa and Compsodes. 



