MORGAN HE BARD I4I 



Males of the present species are distinctive in the spcciaHzation 

 of the median and first dorsal abdominal segments. The median 

 segment is developed similarly to that of P. divisa, but without a 

 raised ridge connecting the projections caudad. The first abdom- 

 inal segment is, however, also similarly specialized in every way, 

 except that the cephalic margin, cephalad of the projections, bears 

 fewer hairs. 



Females of this insect are readily separated, in large part, from 

 those of divisa by the features stated in the discussion under that 

 species. As we have there remarked, however, rare individuals of 

 the present very plastic form show such close similarity to the 

 extremes of divisa toward the present type, that, even considering 

 the sum total of usual differences, correct determinations are in 

 such cases extremely dit^cult. 



Characters of Male. — (Philadelphia, Pennsylvania.) Size very large, form mod- 

 erately broad. Interocular space distinctly less than that between antennal sock- 

 ets.--^ Ocelli well defined, fnter-ocular-ocellar area flattened, ^^^ with surface 

 microscopically roughened. Pronotum with greatest width (normally) mesad,23o 

 but with lateral margins, from this point, slightly more convergent cephalad than 

 caudad ; oblique sulci of disk strongly defined. Tegmina and wings fully developed, 

 normal; tegmina with lateral margins subparallel in mesal two-thirds; wings (in 

 the series) with no to four incomplete and six to eight complete rami of the ulnar 

 vein.-" Median segment supplied mesad with two decided ridges which are weakly 

 convergent cephalad, with their cephalic extremities o\-erhanging the cephalic 

 portion of the segment, which is there and between rather strongly concave; ventral 

 faces of overhanging extremities heavily clothed with short hairs^ the narrow ridge 

 of the cephalic margin of the segment mesad furnished with numerous hairs. First 

 dorsal abdominal segment similarly specialized in e\cry way, except that thecephalic 

 margin is sui^plied with fewer hairs. Sixth dorsal abdominal segment with distal 



females from Sunbury and Lake Wesauken, Pennsylvania, and to a less degree in three 

 from the Black Mountains of North Carolina. In the western series, the less reduced 

 tegmina! condition, through rare, is sometimes found. 



-2^ Variable in the series; slightly greater than (more usual), to slightly less than, the 

 interocellar width. 



229 Very often unevenly weakly concave. 



230 Occasionally slightly caudad of this point. 



231 fhe veins in this species show greater irregularities than in any other of the genus. 

 Frequently the rami of the ulnar vein branch near the distal margin of the wing; while 

 in one specimen this is also true of the median vein, which branches twice in one wing 

 and once in the other. A single siKH-imen has no incomplete rami of the ulnar vein, but 

 numbers liaN'c but a single inconii>Iete ramus. 



MEM. AM. ENT. SOC, 2. 



