82 PROCEEDINGS: BOSTON SOCIETY NATURAL HISTORY. 
the abdomen black, shining, with white pollinose sides, each seg¬ 
ment with a slender, basal, dark cinereous pollinose fascia. Fe¬ 
mora black except the yellowish apices,” hind femora shining black 
on mesal surface, the others not at all shining; “tibiae brown 
black, basal third of all and apex of the anterior ones reddish testa¬ 
ceous ; tarsi reddish testaceous, towards the apex brown, last joint 
black or black brown. Wings slightly brownish cinereous, stigma 
brown.” 
P. fascus Lw. In the Loew' collection three males. Black 
brown. Antennae black, third joint short, rather obtuse. Dorsum 
of thorax brown pollinose, opaque, towards the caudal margin sub- 
sliining. Scutellum black, shining. Metanotum and first abdominal 
segment, except its base which is black, cinereous pollinose; second, 
third, fourth, and fifth segments velvety black on their cephalic 
halves and metallic, shining bronze-colored on their caudal halves 
(a favorable incidence of light is necessary clearly to make out the 
extent of the velvety black portion); the black of the second seg¬ 
ment is to a certain extent cinereous pollinose, and each segment 
has on the sides an indistinct grayish pollinose spot; the fifth 
segment is much longer than the preceding ones; the sixth is much 
larger still, not symmetrical, and wholly shining bronzy except for a 
widely interrupted transverse fascia on its cephalic border. Tibiae 
yellow with scarcely a suggestion of brown; hind tibiae rather 
strongly curved. Femora black except base and apex which are 
yellow; lightly white pollinose except the mesal surface of the hind 
ones, which is shining black; all of them with a certain amount of 
white pile, the pile on the posterior surface of the middle femora 
much longer and denser than elsewhere; flexor surfaces of all with 
rows of very minute black spines. Wings cinereous; stigma 
brown; small cross vein at junction of basal and middle thirds of 
discal cell; veins black; third costal segment longer than the 
fourth. The relative lengths of the third and fourth costal seg¬ 
ments in this and the following species are very difficult to deter¬ 
mine on account of the extremely acute angle at which the first 
vein meets the costa, the brown color of the stigma, and the rather 
large size of the veins, so that the exact point of junction of the 
first vein and costa is hard to see. 
P. nitidiventris Lw. In the Loew collection a single female. 
Blackish cinereous. Antennae black brown, third joint with the 
aj)ex short acuminate. Dorsum of thorax opaque with whitish cine- 
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