212 ENTOMOLOGICAL SOCIETY

212 ENTOMOLOGICAL SOCIETY

Mr.

Fairchild,ⁱⁿ

answer

to a question,stated thatthe_Fijieye- disease in its milder form _lasts, in itsacute _stage,4^or 5 days

and

then gradually dies

away.

Mr. Banks

read the following paper^:

A NEW SPECIES OF THE GENUS HALARACHNE.

By NATHAN BANKS.

In 1847

P

r f-

Allman

described a remarkable mite

which

he

had

discovered in the nares ofa seal fromthe Irish Sea.

Unable

toplace ^itin any ^{of the} then existing genera, he establishedfor it

the

new

genus Halarachne,

and named

the species

H.

halichceri, afterthegenus^{of seal} on

which

^it occurred.

He

characterized thegenus^{as follows:} "

Palps ^{free, filiform,} mandibles_didactyle, sternal _{lip bifid.}

Legs

^{with last} jointsterminated

by two

^hooks

and

anintermediate three-lobed caruncle.

Body

^entire, elongate, subcylindrical, furnished anteriorly with a dorsal _plate; eyes none."

He

_placed the genus ^{in the}vicinity of

Dermanyssus

^; a posi tion

which

I believe to be correct.

For many

years ^littleor no attention

was

_given the mite.

However,

ⁱⁿ 1884, Nehring, ^a

German

mammalologist, obtained specimens from ^the

same

_seal,

and

_publisheda note

upon

^it.

He

maintained thatit

was

related to the Ixpdidae rather than ^to the Gamasida3, _chieflyon account of its shape, general appearance,

and

_especially the posterior position ef the stigmata.

Kramer,

^the acarologist,

saw

the specimens

and

wrotea short article

upon

^the mite, dealing principally with its anatomy.

Haller in 1886 gave ^a few notes

upon

^{it. In} 1889

Nehring pub

lished anothernote

upon

^{it. Its}peculiar habitatis,doubtless, the reason

why

^so

^few

specimens have

come

into the hands of acar- ologists^;

and

thus thegenus ^has rarelybeen mentionedortreated in systematic works.

A

short time ago Dr. Motter brought

me some examples

^{of a} mite given

him by

^{Dr. Hassall,}

who

took

them

from the bron chial tubesofa seal that had died in the Zoological ^Park.

At

first I thought ^{it related to} one of Kolenati's genera of bat-mites, viz., Lepronyssus ^{; but} soon discovered that it

was

a species of Halarachne, closely allied to

H.

halichceri.

The

_generaerected

by

^{Kolenati inthe} Dermanyssida? have not been generally ac cepted, andthere is

much

uncertaintyregarding them.

But

the great difference ⁱⁿ habitat, anddoubtless the position of ^the stig

mata, ^will separate Halarachne fromall other Dermanyssidae.

The

_{breathing pore}is situate _just above the fourth coxa,

and

a line

from

itextends around and behind the coxa. In

Derma

nyssus the stigmata are^{alittlefarther}forward.

The

mouth-parts

OF WASHINGTON. 213

are, however, chelate,

and

of the true

Gamasid

_type.

The

_palpi

are_free,

and

theother characters do not depart

from

those of

Dermanyssus

sufficiently to merit notice.

The

_shape of the dor

sal plate

and

_elongate

body

^{are rather} anomalous, but ^not char actersof importance. ^{1 shall therefore consider}

Halarachne

a genus^ofDermanyssidae,^not greatly.differingfromthe other

mem

bers ofthatfamily^; but

showing

^certain adaptive characters^that

fit it for itspeculiar surroundings.

Our

_{species appears}tobe different from the

European

^form;

and

I describe it as follows:

FIG 15. Halarachneajnericana.: a, sternumofmale; b,stig mata andcoxae; c,mandible; allenlarged. (Original.)

Halarachneamericana,^n. sp.

White, hard _parts pale yellowish; smooth, body^{narrowed in} front, contracted behindthe fourth _pairoflegs, broadly rounded _{at tip; a}dorsal shieldonbasal half, narrow in front,broadest before the middle, then tapering behind, butbroadlyroundedat_tip, showing ^an irregular cross and some_{geminatespots;} asmallround hard spot neartipofbody^atthe anus; legs shortandstout, second pair stoutest, witha few shortbristles, and twoclawsat_tip,the terminal _jointlonger than the otherswhichare subequal^; stigmata justabovethefourth coxae; ^sternal plate truncatein front, sides nearlyparallel at^first, thenconcavelytapering^tothe bluntly- pointed apex.

214 ENTOMOLOGICAL SOCIETY

The male(perhaps not quite adult)^issmallerthan the female,and the abdomendoes notextend

much

_beyond the dorsal _shield, and is

much

narrowed behind; ^{the sternal} plate ^isofaboutthesame_shapeasthatof the female, behind it thereisatransverse line from each end ofwhich there extendsbacka shortdark_line; in themiddleisanelongate pointed genitalopening.

Length 9 ^{2- to 2.8}

mm.

;

$

^1.8

^mm.

Habitat Bronchial tubes ofa seal(Monarchustropicalis}.

HALARACHNE

Allman.

Ann.

&

_Mag. Nat. Hist., 1847.

H. halichceri \\\rc\.

Ann.

&

_Mag. ^Nat.Hist., 1847. Allman.

Sitzungsber. ^d. Ges., naturforsch. Freunde zu Berlin, 1884, pp.

57-64. Nehring.

Zeitschr. f. Naturw., 1885, pp. 46-74. Kramer.

Zool. Anz., 1886,pp. 52-55. Haller.

Humbolclt(Dammer), 1889, p. 315. Nehring.

Habitat

On

Halichcertisgrypkus.

H.americana, ^n. sp.

Habitat

On

Monarchnstroptcalzs.

Dr. Hotter,

who

hadseen the specimens taken from ^the dead

seal, stated thatthe air-passages

were swarming

^{with the mite,} which, however, ^{did not}appear ^to have been the cause of the death of the seal.

Dr. Gill suggested ^that

Mr. Banks

_might, to advantage, ex

change

^thespecific

name americana

to

monarchi,

^fromthegenus of the seal in

which

it

was

found.

He

_objected to

americana

for the reason that thehost of the typespecies ^is quite ^as

Amer

ican asthe host of the

new

_species.

Mr. Banks

objected to adopting ^the

name monarchi,

^{since the} generaof vertebrates

no

less than of arthropods ^are frequently changed.

Mr. Ashmead

^{read a} _paper entitled "

On

the

Genera

of the Xyelinae.* This

was

a technical paper giving ^thecharacteristics of fourgenera ^ofthis

group

belonging^{to the}fauna of the United States

and

_forming a distinct family Xyelidas,

which

he had separated from the Tenthredinidae.

These

_genera are Xyela,

*Publishedin Psyche,Ma}', 1898, p. 214.