58 AMERICAN BLACK FLIES OR BUFFALO GNATS

mid and

hind tarsi (PI. V, fig. 3). AVings slightly grayish, thick veins brown. Ilalteres yellow.

Frons

divergent-sided, above antennae

more

than half as broad as at

upper

angle of eyes, surface hairs brown, upright,

and

regularly distributed; face not as long as frons

and

slightly longer than broad, surface hairs pale

and

shorter than those

on

frons; hairs

on

palpi pale; postocular cilia pale, with an

admixture

of

brown

hairs.

Scutum

with white i3ilosity, w^hich is short, close-lying,

and

regular except

on

margins,

where

it is rather longer

and

looser; a

few

short

brown

upright hairs are present

on

lateral anterior angles

and many

longer ones

on

posterior fourth; pleural tuft grayish white; scutellum with close-lying white pilosity

and

long, upright,

brown

marginal

hairs.

Abdominal

basal scale

brown,

fringe white; segments of

abdomen

almost bare, only a

few

scattered

brown

hairs present, those on apical segments

most

distinct.

Legs

with close-lying, short, pale pilosity

and

longer,

brown,

upright hairs

on

dorsal surfaces^; the nor-

mal

paired apical hairs present

on

the fore tarsi

and

longer hairs also

on

hind tarsal joints 2-3; hind tarsi with basal joint

produced and

second joint with basal scale

and

constriction

(PL V,

fig. 5) ^; claws with sub-basal tooth (PI. II, fig. 11).

Venation

of

wings normal

except that the cross-vein is at slightly

beyond middle

of subcosta hairs

on

basal jDart of

wing

brown, anal marginal hairs white.

Length,

3^ mm.

Redescribed

from

the

two

type specimens

from Las

Vegas, N. Mex.,

August

(H. S. Barber).

These have

the

scutum

indistinctly reddish

and

differ in this respect only

from

a series in the collection

from Los

Angeles, Cal.,

which was

taken in

June and

July. I can find

no

other characters

which would

justify

me

in separating

them

as dis- tinct species.

Male.

— ^Opaque

black-brown.

Face

white-dusted ; antenna? brown, basal

two

joints yellowish; palpi black-brown.

Scutum

with

two

distinct silvery-white stripes

on dorsum;

these stripes are anteriorly slightly convergent

and

terminate with

an outward

curve

on

anterior

margin

of

scutum;

they

do

not extend posteriorly

beyond

the last fourth of disk; lateral

margins and

anterior angles of

scutum

white- pollinose; pleurae white-pollinose; postscutum with silky, white polli- nosity.

Abdomen opaque

^{black at} base, apical three segments slightly shining, first segment below basal scale

and

fifth almost entirely silver}^ white, venter yellowish ^laterally.

Legs

yellow, blackened as follows:

Mid and

hind coxa:'; apices of all

femora and

^tibiae as well as slightly at base of latter; entire fore tarsi; apices of basal joint of

mid and

hind tarsi; apical four joints of

mid and

^all but base of second joint of hind tarsi.

Wings

grayish, thick veins brown.

Halteres with clear yellow

knobs and darkened

^stalk.

SIMULIUM. 59 Hairs

on face pale brown, on palpi brown, postocnlar cilia dark brown. Pilosity

on scutum

regular, rather scalelike, golden yellow, a few

dark

hairs

on

anterior angles

and

longer

and more numerous

hairs of black-brown color

on

posterior fourth; pleural tuft yellow;

scutellum with yellow pilosity

and

long upright

brown

^hairs; basal fringe

and

surface hairs

on abdomen

pale yellow. Pilosity

on

legs almost white, except on

darkened

portions

where

^it is pale brown,

numerous

long pale

brown

dorsal hairs

on

^all joints, the fore tarsi

with paired apical hairs on joints 1

and

3, those

on

joint 2 not so distinct; fore tarsi not thicker than

mid

pair, thinner than fore tibiae;

hind legs as in Plate

V,

figure 4; claws trifid.

Wings and

size as in female.

Redescribed

from

the type specimen.

Las

Vegas, N.

Mex.

(H. S.

Barber).

There

is another specimen

from

the

same

locality in the collection, also taken

by Mr.

Barber.

Nothing

is

known

of the early stages of this species.

Siniulium hunteri, new species.

Female.

—

^{Black; frons shining} black, face white-dusted.

Scutum

three-striped, opaque; jDleurae

opaque

black, gray-dusted.

Abdo- men

opaque, velvety black

on

basal four segments, shining black

on

apical four.

Legs

^black, yellow as follows: Coxse, trochanters,

and

dorsal surface of tibiae of fore legs ; trochanters, bases of

femora and

tibiae,

and

basal two-thirds of first tarsal joint of

mid and

hind legs;

basal third of second hind tarsal joint.

Wings

grayish, thick veins

brown

^; halteres yellow,

darkened

at base of stalk.

Frons with

sides divergent, about two-thirds as

wide

above an- tennae as at vertex, undusted, surface with yellow scale-like pilosity

and

uprightblack hairs on lateral

and

posteriormargins; face thickly white-dusted, about one-fourth longer than broad, as broad as frons at

upper

angle of eyes, surface hairs yellow, with

some

darker,

brown

ones

mixed

: palpi black, pale-haired ; antennae black, yellowish on basal

two and

base of third joints.

Scutum

gray-dusted, with irregu-

larl}^ arranged, golden yellow, scale-like pilosity,

and

with

two

large white pollinose spots

on

anterior

margin which

are each

more

than twice as broad anteriorly as the black space

between them;

these spots are only visible

when

viewed

from

behind

and occupy

the dilated anterior portions of the posteriorly

narrower

black stripe;

viewed

from

in front

and

above the

dorsum

of

scutum

has a central, black,

narrow

stripe

and two

curved stripes

beyond

them, as well as

an

indication of a

narrow

lateral stripe

on

each side; pleural tuft

and

hairs on postspiracular area brownish yellow; scuteUuui with close- lying yellow pilosity siiul upright black hairs.

Abdominal

basal scale

brown

or black, fringe yellow; lateral posterior

margins

of

abdominal

segments gray-dusted, _apical segments with

numerous

black hairs

and

a

few

intermixed pale scales, the hairs at

apex

long.

Legs

with long, yellow, scale-like pilosity

on femora and

upright, dorsal, black hairs

on

these as well as tarsi, the

normal

paired fore tarsal hairs present

on

apices of first

and

third joints; hairs

on

tarsi concolorous with

joints; claws with subbasal tooth (see PI. II, fig. 3).

Wings

with venation normal. Halteres pale yellow,

darkened

at base of stalk.

Length, 3.5-4

mm.

Type.—Cut

^No. 15413,

U.

S. National

Museum.

Type

^locality, Virginia Dale, Colo.,

September

31, 1912 (collector

Bishopp).

Submitted

for identification

by Mr. W.

D.

Hunter

(No.

3065).

One

^specimen

^from

Glenora, British Columbia,

and

another

from

Ainsworth, British Columbia, evidently belong to this or a closely allied species, but their condition is too poor to say for certain.

This species is very close to

virgatum

Coquillett, but the legs are

much

darker in color; this character is very consistent throughout the series of 13 specimens),

and

the frons is also in

most

of the specimens entirely glossy black.

There

is a slight dusting present

on

one or

two

of the specimens in the series, but nothing like the thick white pol- linosity

which

is

found on

that of virgatum.

None

of the specimens of

virgatum

bear

any

label as to habits, but the type series of hunteri

was

taken

on

cows.

The

early stages are

ufiknown

in this species.

Simulium glaucum Coquillett.

Male.

—

^{Black, opaque. Antennse}

^and

^{palpi black; face white-}

dusted.

Scutum

^{with distinct white} pollinosity,

which

is bright silvery

on two

triangular patches

on

the anterior

margin

dorsad of the lateral extensions of the prescutum; central

opaque

black stripe

broad and

well defined anteriorly, linear

and

diffused posteriorly;

on

either side of this stripe is

an

abbreviated linear

mark which

is

evidently the

rudiment

of the dorso-lateral line of virgatum.,

and

nearer the lateral

margin

is a broader black stripe

which

is dif- fused

on margins and

anteriorly abbreviated; pleurae white-pol- Jinose; scutellum slightly poUinose.

Abdomen opaque

black, sides of

segment

below basal scale

and

apical four segments laterally silvered.

Legs

black;

femora

paler at apices; tibiaj

and

basal joints of

mid and

hind tarsi broadly yellow at bases; second joint of hind tarsi pale at base. "Wings ^clear, thick veins yellowish. Halteres yellow, base of stalk blackened.

Face

hairs

and

postocular cilia pale.

Scutum

with white, hair- like pilosity,

which

^is longer posteriorly

and

on the margins;

pleural tuft whitish yellow^; hairs

on

scutellum pale, upright. Basal

abdominal

fringe yellow, in

some

lights

brown;

lateral hairs

on

abdominal

segments white.

Legs

with pale pilosity

and

longer,