10 DIPTERA OF NORTH AMERICA. [PART IV

D. C. ;

New York,

^etc.

Wisconsin

(Kennicott).

The

infuscated marginal cross-vein ^is a very

good

distinctive cliaracter of this species.

This

species is apparently identical with a

European

one, a

specimen

of

which

isin

my

possession. I cannot determine the latterwith

any

degreeof certainty,but the description^of

D.

tristi^

Schum.

agreestolerably well

with

it.

12. D.

liaeretica, n. sp.

%

and 9^.

—

Cervina, tliorace vitta fusca;

antennaj nigrse; rostrum ocliraceum; palpi fusci; alse cinerascentes, iinmaculatoe_; prsefurcse initium apici vense auxiliaris plus minusve oppositum.

Drab colored, thorax with a brown stripe; antennre blackish, rostrum yellow,withbrownpalpi;wings withagrayishtinge,immaculate; the origin of thepr?efurca is nearlyopposite thetipofthe auxiliaryvein.

Long. corp. 0.3

—

0.35.

Head

brownish,finelysericeouswith yellowish;

rostrum

yellow, palpi

brown

; antennae brownish-black.

Thorax

brownish, finely sericeous with brownish-yellow^; this sericeous dust being the thickest

on

the sides,leavesa

brown

^{stripe in}the

middle

_; pleural brownish,or, in

some

specimens, pale; sericeouswith yellowish

;

scutellum

and metathorax

brownish,likewisedustedwithwhitish- yellow.

Stem

of halteres pale

towards

the basis,

knob brown

;

abdomen brown

above, venter paler.

The

forcepsof the

male

israther large

and

conspicuous evenin

dry

specimens^; in fresh specimens the reniform lobes

appear somewhat

club-shaped at oneend,thatis,broaderat the tipthanin the

middle

; the

upper

valves of the ovipositor are

remarkable

for their

extreme

small- ness. Coxae

and

basis of the

femora

yellowish; feet

tawny,

tip of the tibiae slightly infuscated; tarsi

brown towards

the tip.

Wings

(Tab. I, fig. 3) with a slight

brownish-gray

tinge, veins

brown

; stigma pale (slightly infuscated along the cross-vein in oneofthe specimens

from Fort

Resolution).

Tip

ofthe auxiliary vein nearly opposite the origin of the second vein; subcostal cross-vein

removed from

this tip at a distance a littleless than the lengthofthe greatcross-vein; themarginal^cross-veinis near the tip of the firstlongitudinal vein,

and

isplaced insucha

man-

ner that it looks as if the first longitudinal vein

was

incurved towards the second

and

connected with the costa

by

the cross-

DICRANOMYIA.

_^l'

vein, the latter being often indistinct; the submarginal cell is

about

one-third longer than the prtefarca (this relation is, ho\v- ever, variable in different specimens); the seventh longitudinal vein is faintly sinuated about the middle; the position of (ho great cross-vein, as well as the inclination of the vein

which

closes the discal cell

on

theinside, are variable.

Hab. Environs

of

New York,

on the salt-marshes,

common.

Fort

Resolution, 11. B. T. (Kennicott).

D.

hseretica

may

be easilydistinguished from

D.

Hherla

by

the coloringof the thorax,the shortness of the valves of the ovipositor, thegreater distance

between

the tipofthe auxiliaryvein

and

the cross-vein, and, in fresh specimens,

by

the club-shaped _{lobes of} the

male

forceps.

The

teeth

on

the

under

side of the

ungues

are verysmall

and

difficulttoperceive.

The

last tarsaljointis some-

what

incrassated inthe

male and

the interval

between

it

and

the precedingjointisexcised.

There

^isa

European

species, the

name

of

which

I

do

not

know, and which

closelyresembles

D.

lixretica.

13. D. lialterata,

n. sp.

% .—

Fusca; rostrum, palpi et antenn£e nigra; halteres longiusculi; al:e pallide infuscataj, immaculate, ritio--

mate obscuriore;venulatransversa subcostalisabapice veuse auxiliaris loiigitudine stigmatis remota.

Brownish;rostrum,palpi,andantennae black;halteres rather long; wings tinged with pale brownish, immaculate, stigma darker; the subcostal cross-veinisremovedfrom the tipofthe auxiliary vein at a distance equaltothelengthof the stigma. Long. corp.0.3.

Head

brownish,

somewhat

sericeous with yellowish ; antennce

and

palpi black.

Thorax

dull brown, hardly shining above

;

humeral

regionsericeouswith yellowish; theusual stripes con- fluent_; pleuroe brown, sericeous with grayish

below

the root of the

wings and

thatof the halteres;. scutellura

and metathorax brown,

sericeouswith gray; halteres comparatively long, infus- cated, their root pale.

Abdomen brown,

the genitals butlittle paler.

Feet brown,

coxte brownish-yellow; tarsi almostblack.

Wings

tinged with pale brownish; tipofthe auxiliaryvein nearly opposite the origin of the prafurca_; the subcostal cross-veinre-

moved back

of this tip at a distance nearlyequaltothe length of the stigma; marginal cross-vein at the tip of the first longi- tudinal vein; discal cell closed.

12

DIPTERA

OF

NORTH AMERICA. [PART

IV, JIab.

Labrador

(Mr.

A.

S.

Packard,

Jr.)_; four

male

specimens.

This species will be easily distinguished

from D.

hseretica

by

its

brown

rostrum,thedarkertinge ofits

wings and

ofits stigma,

by

the greaterdistance

between

the subcostal cross-vein

and

the tipof the auxiliary vein;

by

its unusually long halteres,

and

in general

by

its darker coloring. I can perceive a tooth at the basis of theungues.

The

excision at the basis of thelast tarsal joint ofthe

male

islikewise distinct.

I possess a

male

specimen from

Canada,

the halteres of

which

are of the

same

length as those of

D.

halterata; the venation

and

coloring of the

wings

are likewise the

same

(the stigma is slightly paler); but the thorax is

brownish

ochraceous, except the space

on

the back, usually occupied

by

the stripes,

which

isbrown. Is itnot a paler variety of

D.

halterata?

14. IK.

l3adia Walk.

% and 9^•

—

^{Fusca,abdominisfasciis pallidis};

pedibus fuscis, femorum apice pallido, alis fusco-nebulosis; stigmate subquadrato, fusco.

Brown,

abdomen

with pale bands; feet brown, tip ofthe femora pale;

wings clouded with brownish; stigma nearlysquare,brownish. Long.

Corp. 0.3—0.35.

Syn. Limnohia hadiaWalk.,List, etc.I,p.46.

Dicranowyiahumidicola 0.Sacken,Proc.Ac.Nat.Sc.Phil. 1859,p.210.

Rostrum,

palpi,

and

antennsa

dark brown

; front

and

vertex grayish-brown.

Thorax tawny

with

more

or less confluent

brown

stripes; a faint yellowish, sericeous reflection in the

humeral

region

; pleura3

brown, with some

paler spots; halteres pale,

knob

infuscated; coxse pale; feet

tawny

; a pale

band

atthe tip of thefemora.

Abdomen

tawny, with pale

bands on

the incisures;

male

forcepslike Tab. Ill, fig. 2; ovipositor ofthe female ferru- ginous.

Wings somewhat

tinged

with

grayish

and

faintlyclouded with

brownish

; a pale

brown

cloud at the originof the proefurca;

another,

rounded

one, atthe inner

end

of the submarginal cell

;

the cross-veins likewiseclouded; stigma brown,intheshapeof

an

elongated square.

Tip

of the auxiliary vein generally a little

beyond

the origin of the prfcfurca,

sometimes

nearly oppositeit,

thecross-vein very near its tip.

Eah. Washington,

D.C.;

Trenton

Falls^; Connecticut;

Canada.