80 PROCEEDINGS : BOSTON SOCIETY NATUR AL HISTORY. 
tarsi yellow or brownish yellow to a varying extent. Wings gray¬ 
ish ; stigma brown; veins black; small cross vein at a point 
apicad the junction of the basal and middle thirds of the discal cell, 
but before the middle of that cell; third costal segment about twice 
as long as the fourth. Halteres black except base of peduncles 
yellowish. 
JP. atlanticus sp. nov. Two males and three females. New 
Bedford, Mass., Hough; Montgomery Co., Pa., C. W. Johnson. 
Length 3 mm., length of wing 5 mm. Brown black, mostly gray 
pollinose, with wholly yellow legs and very distinctly banded abdo¬ 
men. Antennae brown with very fine whitish pubescence, third 
joint short, oval, obtuse. Dorsum of thorax and scutellum black 
brown pollinose, toward the sides and on the humeri more grayish. 
Pleurae, metanotum, and coxae gray pollinose. Legs wholly yellow, 
appearing more or less silvery gray pollinose according to the inci¬ 
dence of the light, except the tips of the tarsi, which are black. 
The four anterior femora on the flexor surfaces and all the tibiae 
have rows of extremely minute black spines. Abdomen wholly 
opaque. First segment wholly gray pollinose except a narrow 
black cephalic border. Second segment wholly gray pollinose, the 
pollen thinner on the middle of the segment, so that in some speci¬ 
mens there seems to be a faint median, transverse, black brown fascia. 
Third, fourth, and fifth segments wholly gray pollinose, except a 
cephalic, transverse, blackish brown fascia which gradually fades out 
toward the sides and a median, caudal, blackish brown spot which 
is connected with the cephalic fascia. On the dorsum of the abdo¬ 
men the relative widths (measured cephalo-caudad) of the blackish 
brown fascia and the gray pollinose portion vary in different speci¬ 
mens, sometimes the one and sometimes the other being the wider; 
the sides of the segments are, however, wholly gray pollinose. The 
sixth segment is wholly gray pollinose except a small brownish 
black spot cephalad; this segment is rather large and is divided 
into three very unequal portions by two dorso-ventral clefts, both of 
which are to the left of the median line. The one nearest the 
median line is about halfway to the lateral border, while the one 
furthest laterad cuts off not over one sixth of the segment. 
Remainder of genital apparatus yellow. Halteres with yellowish 
brown peduncle and black knobs. Wings grayish hyaline, veins 
black; small cross vein at about the junction of the basal and 
middle thirds of the discal cell; third costal segment about equal to 
the fourth. 
