Article beginning on page 355.
Psyche 5:355-362, 1888.

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the antepenultimate segment ; appen-
dages (2) short (3 mm.) foliaceous,
broad, obtuse, wings hyaline, costa yel- low ; pterostigma elongated, fuscous ;
me~nbranule blackish gray ;the subnodal
sector sometimes not bifurcated ; 13-16
and 18 antecubitals ; 10-13 postcubitals ; 4-5 areoles beneath the pterostigma.
Length 51-60 mm. ; alar expanse 74-86
mm. ; pterostigma 4 mm.
HAL Labrador ; Fort Resolution
and Saskatchewan, Brit. Amer. ; one
8 White Mountains, N. H.
This species is very much like A.
torealis from Europe; I am not able
to separate the males, except that the T spot on the front has a larger and more
rounded head in A. se$tedonaZis;
the appendages of the female are more
widely separated at the base, less broad and somewhat incurved in the European
species. I consider the two species as
local varieties, but owing to the obvious difference in the appendages of the fe-
males it seems more prudent to keep
them separate for the present. I have
compared 15 specimens of A. septen-
trionalis and g specimens of A. borealis from Lapland, Sweden, Silesia and
Switzerland. Both are arctic species.
Many years ago I saw a specimen from
the Wilui River, Siberia, but this speci- men is not at hand and as at that time
I believed A. sitchensis to be the same
species I am unable now to say if the
Siberian specimen belongs to A. borea-
Us.
DESCRIPTIONS OF SOME NEW NORTH AMERICAN
DOLICHOPODIDAE.
BY WILLIAM M. WHEELER, MILWAUKEE, WIS.
(Continued from 9.343.)
GYMNOPTERNUS POENITENS, n. sp. 8
Length 2.75 mm. ; length of wing 2.75mm. Dark metallic green. Face moderately
broad, covered with hoary dust. Antennae black throughout, third joint large and of the usual shape, somewhat pointed and
covered with conspicuous whitish pubes-
cence; pubescence of the arista, which is inserted in the middle of the dorsal con- tour of the third joint, appressed and
perceptible only with di-fficulty. Front rather dull metallic green; cilia of the in- ferior orbit white. Thoracic dorsum shin- ing blackish green, posteriorly with a bril- liant golden reflection, apparently without any traces of dust. Scutellum blackish
green with a golden reflection, bearing a few black hairs besides the usual setae. Pleurae anteriorly metallic greenish black, posteriorly black, overlaid with hoary dust. The yellow tegulae have black cilia. Abdo- men blackish green, lacking the golden
reflection of the thorax and scutellum;
venter black, dusted with white; hypo-




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pygium black ; lamellae large, elongate
oval, brownish yellow, posterior edges
black, irregularly crenulated and fringed with weak black bristles; the numerous
smaller and mole concealed appendages
of the hypopygiutn yellow. Coxae and
legs black throughout; femora with a faint metallic green reflection. Fore legs smooth, tarsi equaling the tibiae in length; median femur with a preapical bristle, median tibia with two setae on its posterior face, sepa- rated by a distance equal to + the length of the tibia; hind femur with a preapical bris- tle, hind tibia with four or five spines along its posterior-face. Hal teres pale dull yellow. Wings smoky gray, becoming almost black
along the costal margin ; veins black, the third and fourth longitudinal veins gently converging and, for a Gymnopternus, very closly approximated at their tips. Anal
angle very obtuse, giving the wing a lance- olate outline.
HABITAT : Milwaukee Co., Wis.
Gymno#ternus joenitens is to be ad-
mitted to the group comprising Loew's
G. scotias, G. barbatt~Zus, and G.
tristis, all of which differ from the
other described North American spe-
cies of the genus in having the pre-
vailing color of the feet black. G.
joe~zitens differs from G. scotias in
having the cilia of the inferior orbit
white, the feet entirely black, the hypo- pygial lamellae large and in great part
yellow; from G. barbatulus and G.
tristis, G. toenitens differs in the
more hairy third antenna1 joint and
its completely black legs. Both of
Loew's species also have the cilia of
the inferior orbit black. The course of
the third and fourth longitudinal veins
is very different in G. poenitens from
what it is G. tristis, in which species, according to Loew, there is only a
slight convergency, though he men-
tions in a note a male with a &' con-
siderably stronger convergency of the
third and fourth longitudinal veins,"
He considers this specimen to be
merely a striking variety of G. tris-
tis .
CHRYSOTUS WISCONSINENSIS, n. sp. 3.9.
Length 2.5-2.75 mm. ; length of wing 2.- -
2.25 tnm.
Splendid metallic green. Antennae en-
tirely black ; third joint small, rounded, rather hairy; eyes completely meeting on the face in the male ; in the female the face broad, covered with silvery white dust, and crossed by a marked tranverse ridge a little above the oral margin. Palpi black, small and somewhat concealed in the tnale; con- siderably larger and covered with silvery white dust in the female. Front broad in both sexes, triangular, widening towards the occiput, metallic green, inclining to violet, somewhat dimmed by a layer of fine dust; cilia of the superior orbit black, those of the inferior orbit glistening white. Thoracic dorsum and scutellutn , bright
golden green, overlaid with a thin layer of yellowish white dust, which is thickest on the humeri : pleurae metallic green, rather thickly covered with white dust, cilia of the tegulae white. Abdomen bright golden
green, rather thickly covered with black hairs ; terminal segments more blackish ; hypopygiutn of the male quite large, barely concealed, appendages glistening, black. Legs quite hairy; fore coxae yellow, their extreme bases metallic green in front ; theii- tips with a tuft of black hairs. Anterior tarsi blackened from the tip of the second joint; hind legs somewhat robust, tarsi
equaling the tibiae in length, black and quite hairy, only the base of the metatarsal



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ioint yellow; apical third of the tibia
blackened. The mature male has a rather
broad metallic black band around the apex of the hind femur, leaving only the extreme tip yellow. In the female and immature
male this band is represented by a more or less distinct black or fuscous spot. In the male there are several (about six) robust spines on the posterior face of the hind tibia and three less conspicuous and obliquely inserted setae at the tip of each of the four posterior femora. Halteres bright yellow. Wings grayish hyaline with black veins;
the posterior cross-vein is some distance in front of the centre of the wing.
HABITAT ; Milwaukee Co., Wis.
The coloring as described above is
constant in five males and three females in my collection. The species is allied
to Chysotus ~aIZi'es, Loew. It dif-
fers in having the eyes completely con-
tiguous in the male and not separated
by a linear white face, and in having
the hind legs very differently colored.
In Loew's species the hind legs are yel- low; "even the tarsi are only slightly
dusky towards the tip." Loew's
specimens could hardly have been
immature individuals of C. wis-
consinensis as I have three immature
specimens which differ from the mature
ones only in having the shining black
subapical band of the hind femora
represented by a fainter spot.
CHRYSOTUS PRATINCOLA, n. sp. $
Length 2.25 mm. ; length of wing 2 mm.
Palpi brown ; antennae black, third joint small, rounded, with apical arista. Face broad for a male Chrysoius, opaque black, as is also the front in my specimen. Cilia of the superior orbit black, those of the in- ferior orbit sparse, whitish.
Thoracic dor-
sum, scutell~~m and abdomen metallic green, rendered almost opaque by a thick layer of brown dust: pleurae opaque, black. Cilia of the tegulae pale yellowish. The sparse hairs covering the abdomen dirty white. Hy- popygium black, concealed ; venter of a paler and more bluish metallic green than the terga. Coxae opaque black, tipped with yellow and each provided with a tuft of glistening white hairs on the anterior face; these hairs are longest on the fore come. Legs not very
hairy; femora black with metallic green
lustre, especially on the hind pair; their apices and extreme bases yellow; tibiae
yellow covered with short weak black hairs ; tarsi yellow, blackened on all the feet
from the tip of the first joint; hind tarsi scarcely as long as the hind tibiae. Hal- leres honey yellow. Wings hyaline, "with very faint grayish tinge; veins black; the black costa is moderately incrassated from its juncture with the first longitudinal vein to the tip of the wing'; towards which it gradually diminishes in thickness; pos- terior cross-vein in front of the middle of the wing.
HABITAT : Saline Co., Nebraska.
The moderately thickened costa, the
broad face and the coloring of the
femora place this species near Loew's
Chrysotus subcostatus. From this
species C. patincola may be dis-
tinguished by its very thick covering
of brown dust and the pale hairs cover-
ing the abdomen. Perhaps a greater
number of specimens than either
Loew or I have had the opportunity to
examine, may show the two species to
be identical.
CHRYSOTUS CHORICUS, n. sp. 8
Length 2. mm; lengh of wing 1.75 mm.
Bright metallic green. Palpi pale, fus-




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cescent towards their bases. Face very
narrow, the eyes almost meeting, covered with whitish dust. Antennae deep velvety black. first joint somewhat slender, third joint broad and hairy, ending anteriorly in a short and blunt point, above which is in- serted the arista. Front metallic green, its edges at first parallel, then diverging pos- teriorly; cilia of the inferior orbit pale. Thoracic dorsuin and scutell~~m bright
metallic green, with scarcely any dust;
pleurae greenish black, dusted with white. Tegulae with glistening white cilia. Ab- domen short, cylindrical, and like the tho- racic dorsum, bright metallic green, rather thickly covered with stiff black hairs;
its terminal segments more blackish ; ap- pendages of the hypopygiurn pale, hairy. Coxae black, with yellow tips, the anterior pairs with tufts of rather long white hairs. Legs very hairy; femora shining metallic green, tips and extreme bases pale yellow; fore tibiae pale yellow; median tibiae grow- ing blackish towards their apices.
Anterior
tarsi black excepting the base of the meta- tarsal joint, which is yellow; pulvilli not perceptibly enlarged. Hind legs more ro- bust than the anterior, tibiae and tarsi shining blue-black ; each femur with a row of black hairs, running from the base to the apex on the outer edge and increasing in length distally; hind tibiae and tarsi thickly clothed with rigid black hairs; the forn~er with five spines on the posterior face, the latter robust, not perceptibly tapering till the fourth joint. Peduncles of halteres
brown, capitula honey yellow; their tips sometimes blackened, more often only
slightly infuscated. Wings grayish hyaline with black veins.
HABITAT : Milwaukee Co., Wis.
This species is related to C. obli-
quus, Loew, and somewhat more closely
to C. ajflnis of the same author. It
differs from both in having the cilia oi the tegulae white, from C. obliyuus.,
also in the hirsuteness of the hind
tibia and tarsus.
CHRYSOTUS PICTICORNIS, Loew. 8 9
Length I. 5-2.25 mm. ; length of wing 1.75- 2. mtn.
Palpi pale, somewhat blackened at their
bases, and clothed with a few scattered, long blackish hairs ; eyes contiguous on the face in the male ; face of the female moderately broad, dusted with white and presenting
near the oral margin a slight swelling, on each side of which, abutting on the orbit lies a small rectangular black spot. An- tennae in both sexes with the basal joint pale yellow, the two apical joints deep black, clothed with rather abundant pale pubescence; arista inserted apically. Front and occiput metallic green, dulled by a layer of yellow- ish dust; cilia of the superior orbit black, those of the inferior orbit glistening
white, very conspicuous in some specimens. Thoracic doi-sum and scutellum metallic
green, considerably dimmed by a layer of yellow dust, thickest on the anterior portion and on the humeri ; pleurae metallic green, inclining to blackish, dusted with white. Tegular cilia black. Abdomen coppery
green, not very vivid, with the incisures narrowly blackish, the terga
covered with
short pale hairs which appear black in some lights and are somewhat more appressed in the female than in the male; hypopygium
inconspicuous, its longer appendages pale yellow. Legs pale yellow, moderately hairy; fore coxae blackened only at their extreme bases ; posterior coxae with their basal halves blackened. Tarsi blackened only towards
their tips. Hind femora with prominent
preapical bristle. Halteres honey yellow. Wings grayish hyaline; posterior cross vein a considerable distance in front of the middle of the wing.




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June 1890.1 PSYCHE. 359
HABITAT : Milwaukee Co., Wis.
Loew's description of this insect is
so brief, being taken from a single
imperfectly preserved specimen, that I
have seen fit to describe it again. The
small size of the species, the pale color of the first antenna1 joint, which Loew
describes as red, but which is really
pale yellow in well-preserved speci-
mens,-and the locality (Loew's speci-
men was from Illinois) are proof suffi-
cient that my specimens are true
B. picticornis. The species is com-
mon in damp woods near Milwaukee.
DIAPHORUS SATRAPA. n. sp. $
Length 2 mm. ; length of wing 1.75 tnm.
Palpi rich brown; face narrow, covered
with thick silvery white dust; antennae
brown, hairy ; third joint pointed
(with dorsally inserted arista?) Front and occiput bronze black, with violet reflection, shifting to cupreous posteriorly, the surface covered with very fine appressed white
hairs ; inferior orbit thickly powdered with white dust; cilia glistening white. Tho- racic dorsum vivid blackish bronze, with a shining violet patch on the disc, bordered on each side by a broad and obscurely de- fined, cupreous band. Scutellum flattened, vivid bronze green. Pleurae bronze green, covered with silvery dust; there is a patch of thick white dust on the hutnerus, very con- spicuous when the insect is viewed from
above, and extending down to the insertion of the fore coxa. Tegnlae pale yellow, with white cilia. Abdomen slender, covered with rather stout black hairs; basal segment
bronze green; second and third segments
pale yellow, the latter bronzed on its pos- terior border; remaining segments vivid
blackish bronze ; hypopygium brownish,
sc,u-cely protruding, covered with pale yel- low hairs. Coxae and feet pale yellow,
somewhat slender and not very hairy; fore come bearing on their anterior faces several long yellowish brown hairs; median coxae similarly adorned, one of the hairs, however, is very long and blackish; median femur
with two stout blackish spines near the apex- Fore and median tarsi blackened towards
their tips, the former very slightly, the latter more conpicuously. Hind legs only model-- ately hirsute; apical half of each femur brown on the upper face; tibiae brownish and the tarsi, excepting the extreme base of the first joint, deep brown. Halteres honey yellow. Wings more brownish than gray-
ish hyaline, owing to the brown veins and the rather thick covering of microscopic brown hairs; posterior cross-vein very near the middle of the wing; third and fourth longitudinal veins gently curved but still parallel; anal angle not prominent as in several other species of the genus.
HABITAT : Saline Co., Nebraska.
My single specimen of this beautiful
Diai>Jiorus has lost the tips of the an- tennae and of several of the tarsi, so that I can assert nothing in regard to the in- sertion of the arista or the development of the pulvilli. The other form-
characters, however, agree so well
with those of other species of Dia-
@orus that I do not hesitate to assign
it to this genus. The color ofthe abdo-
men is very unlike that of any described North American. DiQhorus,, but ap-
proaches the European D. trip/Zus,
Loew, D. hoff'mannsegg& Meigen
and Z). oculatus, Meigen, being' close-
ly allied to the latter. These European
species form a subgeneric group cha-
racterized by the more or less extended
yellow band encircling the base of the
abdomen. Heretofore 110 members of




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360 PLS'~'TE?E. [June 1800.
this group have been described from
America ; in all of Loew's species the
abdomen is metallic green (or in D.
oficzts black) throughout. Loew re-
cognized the fact that the American
dia//Iori are especially heterogeneous,
but with his usual fine judgment de-
clined to resolve the genus into several. Such an attempt even at the present
time, would be unwise, as I am con-
vinced that there are still many North
American species awaiting descrip-
tion.
Length 2.75 mm. ; length of wing 2.5 mm. Palpi very prominent, as long as the face, from the insertion of the antennae to the oral margin ; glistening white, golden yellow at their bases, with a few long silvery hairs on their edges. Face broad, covered with yellow dust and presenting a somewhat
shallow, v-shaped depression near the oral margin. Antennae black, apical joint more piceous, hairy, twice as broad as long, reni- form with subapical arista. Front and oc- ciput broad, without any tendency to con- tiguity in the eyes, covered with the same glistening yellowish dust as the face ; cilia of the superior orbit short and black, those of the inferior orbit very long and silvery white, forming a conspicuous, though not very dense beard when the head is seen in profile. Thorax and scutellun~ golden
green, their brilliancy much subdued by a thick layer of yellow dust most abundant on the anterior half of the thoracic dorsum and on the lateral corners of the scutellum; pleurae greenish black, dusted with white, the yellow dust of the thoracic dorsum ex- tending over the humeri on to the anterior pleurae a short distance. ~egulae pale yellow with yellow cilia. Abdomen metallic green, not vivid and less golden than the thorax and scutellum ; intersegmental incisures narrowly black as are also the short robust hairs covering the segments ; hypopygial appendages pale yellow. Coxae concolorous with the pleurae, dusted with white. Femora slightly enlarged, black on their inner
and lower faces, which are dusted with
white but metallic green on their upper
faces; knees rather broadly pale yellow; tibiae and tarsi black, inclining to piceous at the jointt, ; pnlvilli dilated on all the feet.