110 DIPTERA OF NORTH AMERICA. [PART IV

palpi exceediugly minute,inserted at its tip. Antennse very ^{short, 12-} jointed: basal jointof theflagellumverystout; thetiooapicaljointsonly areprovidedwith longhairs. Thoraxelongated,extendedanteriorly intoa long, cylindrical neck;

mesonotum

strongly projecting over the coUare.

Tibiaewithoutspurs atthetip. Empodiaindistinct ornone.

The head

isproportiohally small; the antennae are 12-jointed, hardly longer than the

head

; the first joint is veryshort,

and

still shorterinthe

male

than in thefemale; the secondis longer

and much

stouter

than

the first, obconical; the thirdis ineras- sated, although less stout than the second joint; it

seems

to represent the coalescence of several joints; it is

more

or less

rounded

inthe male,

and more

elongated, almost conical in the female; the

remainder

of the

antenna

is filiform; the

two

apical joints in the

male

areelongated, slender,

and

considerably longer than the precedingjoints, a difference

which

is not so striking in the female; the intermediate joints are cylindrical, those nearer to the stout basal joint of the flagellum are

sometimes

veryshort

and

broader than long; the

two

jointsof the scapus bear

some

shortbristles; the

pubescence

of the flagellum isalmost imper- ceptible; the

two

^apicaljoints only bear

some

longbristles,

very

characteristicfor the genus.

The

front is

narrow

in T.

magna and

broader in T.

muUehris

; the eyes are slightly eraarginate

on

theinside, to leave

room

forthe insertion of the antennae

and

veryclosely

approximated,

almost contiguous,

on

the

under

side of thehead.

The

palpi, inserted at the tipof the rostrum, are exceedingly minute,

and

theirjoints

seem

tobealmostcoalescent;

they

seem

to

be

verylike those of

Elephantomyia

(compare, as to the structure of the palpi of this genus,

Mr. Loew's

figures,

Linn. Entom. Y,

Tab. II, fig. 12, 20, 21).

The

rostrum is slender,perfectlylinear,with an almost imperceptible pubescence;

both species described

below have

itabout once

and

a half the length of the

head and

thorax takentogether.

The

thorax is ratherlong,

and

remarkableforthe great

and

un- usual

development

of the

mesosternum,

in

consequence

of

which

the fore coxae are ata considerabledistance from the intermediate ones; the collare is entirely concealed

under

a projecting gib- bosity of the

mesonotum

;

on

the

under

side, the prothorax is

extendedinto a long, narrow, cylindrical neck, to w^hich the

head

isfastened; the

metathorax

is also

much

developed, rather long

and

horizontal.

The

feet arelong

and

slender; theirpubescence

TOXORRHINA.

Ill hardlyperceptible^; the last jointof the tarsi of the

male shows oa

the under side, at the basis, the excision characterizing the

male

sex in

many

genera.

The

^tibiae

have no

spurs atthe tip,

and

the

empodia

are imperceptible.

The wings

(Tab. I, fig. 6,

wing

of T.

magna)

are rather short forthe size of the body,

and

not broad.

The

first longitudinal vein is short

and

joins the costavery early

and

very soon

beyond

the origin of the secondlongitudinal vein; the

mode

of this junction of the firstvein with the costa is also peculiar; instead of

running

parallel tothe costa

and

then taking a

sudden

turntowardsit(as in

most

Tipididsehrevijmlpi), .the first vein gradually converges

towards

the costa

and

finally coalesceswith it, sothat,

beyond

theirjunction, the costa

becomes much

stouter.

The

auxiliaryvein isvery closely

approximated

tothe firstlongitudinal

and

ends inthe costa almost opposite the origin ofthe second vein; the subcostal cross-vein isnotfar from

itstip; there is

no

vestige of a marginal cross-vein.

There

is

no suhmarginal

cell, as the

second

longitudinal vein does not emit

any

othervein; the first posterior cell follows

immediately

after the marginal cell.

The

fourth vein starts, as usual,

from

the fifth, very near the basisofthe wing, beingslightlyarcuated atits origin,

and

connected at this placewith the first vein

by

a small, but very distinct cross-vein.

A

^thickening of the alar

membrane

almost

always

exists atthis place in the Tipulidee

;

sometimes

it

assumes

the

appearance

of a vein; in the present case, however, thiscross-vein isparticularly distinct, because the origin of the fourth veinis a little

more

distant than usual

from

the basis of the wing.

Of

the

two

branches of the fourth vein, the posterior one isforked,

and

a cross-vein

between

this fork

and

the anterior

branch

closesthe discal cell.

The

sixth vein isveryclosely

approximated

tothefifthfor

more than

one-third of its course,

and

then suddenly diverges at

an

acute angle

from

^it; in

some

specimens thebasal portions of these veins are so near

each

other as to appear coalQscent; a careful examination, however, proves that they run alongside of each other.

The

seventh vein is nearlystraight.

The

forceps of the male, asfar as its structure can be ascer- tained on a dry specimen,

seems

to be

somewhat

like that of

Elephantomyia,

that is, it consists of a pair of subcylindrical basal pieces, to

which two

pairs of eusiform,

horny appendages

112

DirTERA

OF

NORTH AMERICA. [part

IV.

-y

are attached.

The

ovipositor of the female has long, slender, almost imperceptibly arcuated valves.

The

relationship of

Toxorrhina

with

Elephantomyia and Rhamphidia

is evident,

and

principally indicated

by

the pro- longed rostrum,

common

to the three genera, the absence of the marginal cross-vein,

and

the structure of thefeet.

Toxorrhina

iseasilydistinguished

from Elephantomyia hj

\hQ venation ofthe wrings, the submarginalcell ofvv'hich is

wanting

;

by

the structure of the antennae,

which

are 12-jointed

and have some

longerbristles

on

the apical joints only,

whereas Elephan- tomyia

has long verticils

on

allthe joints,

and by

the structure ofthe thorax, the collare being entirely concealed

under

the pro- jecting gibbosity of the

mesonotum,

the

mesosternum being

unusually developed,

and

the

metathorax

also rather large

and

horizontal.

The

venation of

Toxorrhina

is

unique among

the Tipulidee,

and

it isnot easyto decide the disappearance of

which

veins has

brought

it about.

The wing

of EllipAera (Tab. I, fig. 10)

may

afford an explanation. If

we imagine

that the first

and second

veins of Elliptera, already

very

closely approximated, coalesce with each other,

we

obtain a venation notunlike that of

Toxor-

rhina.

In

this case

what we have

called above the secondvein,

would

in realitybe the third.

Whether

this explanation is the true one, I

do

not pretend to decide, but it is

worthy

of notice that several genera

among

the

Limnohina anomala show

a ten-

dency towards

the coalescence of the veins near the costa {Antocha, Styringomyia, etc.;

compare

above, p. 101).

The genus Toxorrhina was

for the first time described

and

figured

by Mr. Loew

in

1851

{Linnsea Entomologica, Yol.

Y,

_p.

400, Tab. II, ^fig. IT).

The pamphlet on

the

amber

fauna, pub- lished a year earlier, contains a

mere mention

of the generic

name,

without description.

The

article in the

Linnsea

describes

Toxorrhina

fragilis,fromPorto Rico,and,

by way

ofillustration, introduces a

meption

ofthefossil species,

assuming

theirgeneric identity.

The

^latter,however, as I have

shown

inthe preceding genus, are, to all appearances, Elephantomyiae, asthey possessa

submarginal

cell, verticils on all the joints of the flagellum, etc.'

' Dr. Schiner (Reise,etc. derNovara, Diptera, p. 33) doubts the pro- prietyof using tlie

name

Toxorrhinafor T.J'raijilis and the other living species, instead ofleavingitwiththefossilspecies, forwhichitwas origi-

TOXORRHINA.

113

In 1865

{Proc. Fhilad. Ent. Soc. 1805, p. 227) I published

two North American

Toxorrhinae,

and gave

a detailed descrip- tion of the generic character.

The genus Limnohiorhynchus Westw. (Annates

de la Soc.

Entom.

de

France,

1835,p.

683

; the description has

been

repro- nallyintended.

He

says: "_If Loew introduced this genus for several

amber

Diptera,which are provided with a submarginal cell,thecircum- stancethatheafterwards addedtoita speciesfrom Porto Rico, whiclihas

110suchcell,does not prove that the absenceofthis cellisacharacter- istic

mark

ofthe genus,etc." Itseemsto

me

that the question, towhich of the two genera does the

name

Toxorrhina _rightfully belong? to T.

fragilisandcongenersortothe threefossilspecies?mustbeansweredby another very naturalquestion,towhichofthe two does Mr. Loew's de- scription of Toxorrhinaapply? Toxorrhina has been merely

named

and notdescribedinthe pamphletBernsteinundBernsieinfauna, 1850; ithas been describedinthe followingyearonly, intheLinna.a. Thisdescription applies to T. fragilis only,andnottothe threefossilspecies. Thecircum- stance that thesefossil species are provided withasubmarginalcell,the circumstanceupon whichDr.Schiner'sargumentrests,has upto thisday never been mentioned by Mr.

Loew

in print; on the contrary,he saj's expresslythat these species areabsolutelysimilarto T.fragilis,withregard to theirgeneric characters(Mr. Loew'sexpressionshavebeen quotedabove, p. 107); in otherwords, destitute ofa submarginal cell. As late as iu 1861, in a lecture held before the meetingofthe

German

naturalists in Kiinigsberg (Ueber die Dipternfauna des Bernsteins), Mr.

Loew

says:

"

Among

the amber Diptera I also found three species of aTipulideous genus,whichIcalledToxorrhina;itisremarkable

....

fortheabnormal venation of ^its ivings. Afterwards I became acquainted with a living representative of the same genus," etc. Can it be affirmed, after this, that Mr.

Loew

introduced the genus Toxorrhina for certain species pro- vided with a submarginal cell?

He

could not have very thoroughly examined the amber species,ashe overlooked the presenceofthatcell

;

T.fragilis,on the contrary, he described and figured correctly. There can benodoubt,Ithink, thatthelatteristobe considered asthetypeof the genus.

When

^I discoveredElephantomiiia, I had no other sourceof information about Toxorrhina but theabove quoted description. In con- sequence, Idrew anelaboratestatementofthe differencesbetween Toxor- rhina as I found itdescribed and

my

specimens{Proc. Acad. Nat. Sci.

Philad. 1859,p.221),andcalledthe latterElephantomijia.

My

purpose, in publishing this somewhat lengtliy explanation, is to justify the course I have adopted,which,owing to the intricacy of the question,has been misunderstood^; and 1 hope that the eminent dipter- ologist,whose.collaboration I haveenjoyed

now

for twelve yearsin the publicationofthe NorthAmericanDiptera, willnottakeoffenceif, in this instance,

my

viewsare not inaccordance withhis.

8 July1838.