INSECTS

DIURNAL LEPIDOPTERA.

By

W. H. Edwards.

Family,

PAPILIOlSriD^.

Sub-family, Papilionin-^.

Genus, Colias, Fabricius.

1. C. Hecla, Lefebvre.

One

female

was

taken atQuickstepHarbor,GulfofCumberland,lati-

tudeGGo. This speciesinhabits Southern Greenland

and

regionstothe westward. Ithas been attributed to Iceland, but, asis

now

supposed^

erroneously. It alsoinhabitsSouthern Lapland.

Mr. M'Lachlan,in hisEeportonthebutterfliescollected

by

the recent British Arctic Expedition, statesthat C.Hecla

was

takenasfarnorth as latitude 81°45', at

Hayes Sound

;

and

he gives information obtained from CaptainFeilden, E. N.,attached totheAlert asnaturalist,onthe habits ofLepidopterain thesehighlatitudes. ^''

During

the short period

when

there is practically

no

night, butterfliesare continuously on the wing, supposingthe sun'ssurface notto be obscured

by

cloudsor pass- ing

snow

showers.

That

about one

month

in each yearisthe longest periodin

which

itisiDOSsibleforthese insects to appearin theperfect state,

and

that about six

weeks

is the limitof time allowed to plant- feedinglarvce,duringall therestof theyeartheland beingunder

snow and

ice." Mr. M'Lachlan doubtsif thereis sufficient timein eachyear forthepreparatory stages of thebutterfly,

—

egg, larva,

and

chrysalis,

—

and

isdisposed to think that

more

than one yearisnecessary. In the northern United States, the larvoB of Coliasfrequently pass the winter

when

half-grown,orevenyounger,

and

Ithinkitprobablethisisthe habit ofHecla.

From two

tothree

weeks

attheendof theshortArctic

summer, and

lesstime atthe beginninginthe followingyear,

would seem

to suf- ficefor thewholeroundof transformations.

InDr. Staudinger's Catalogue, Colias Boothii, Curtis, is put

down

as a

synonym

of Hecla; but, in the oi)iniou of Mr. M'Lachlan, the

two

are distinct species.

155

It isremarkable that thecollection of butterflies

made by

the British Expedition, between latitude 78^

and

82°, welltowardthe Arctic Sea, shouldexhibit agreater

number

of species,namely, 5,thanis

known

in SouthernGreenland,

where we

aretoldbut 4species

have

hithertobeen taken,

and

this northern seriesdoesnotembrace thegenus Chionobas,

one

or

two

species of

which

arefound inGreenland. Besides C.Hccla

and Argynnh

Polaris,taken

by

Mr. Kumlien, were Argynnis Charidea,

Lycmna

Aquilo, and,

most

surprising of all, ChrysojihanKs Fhlceas, a species represented throughout the northern United States under a slightly differentform,Americana.

Family,

NYMPH

ALIDiEl.

Sub-family,

NriviPHAxm^.

Genus, Argynnis, Fabricius.

1. A. Freya, Tliuuberg.

Two

males were taken in SouthwestGreenland. Thisspeciesis dis- tributed overthe boreal regions of both continentsj in America,from Greenland to

Alaska

_j

and

itfollowsthe

Eocky

Mountainsasfar to the south as Colorado. Itis subjecttoverylittlevariation.

2. A. Polaris, Boisduval.

One male was

taken at Quickstep Harbor. This speciesis

more

re- strictedin distribution thanFreya, and, so far as

known,

is limited to ZSTortheast America,from Labrador to the ArcticSea. It

was

taken

by

theBritish Expeditionas far to the north as latitude 81° 52',

and by

the

American

Expedition (Polaris) at 81°50'. It varies

much

in color,

and

the exami)le sent

me by

Mr.

Kumlien

isremarkably melanic onthe uppersurface, thehindwingsespecially showingscarcely

any

fulvous.

Sub-family,

Satykin^.

Genus, Chionobas,Boisduval.

1. C.Semidea, Say.

Oeno, Boisduval.

Two

males were takenat Quickstep Harbor.

One

of these has the uppersurfacedark blackish-brown,

and

the discal belt on hind wings beneathdistinctlyoutlined

on

both edges.

The

other is lightorpale black-brown,

and

the beltisalmost lost in the dense markiugs which cover the wing.

But

specimens from the

White

Mountains of

Xew

Hampshire show

similar variation. This species inhabits Labrador,

and

the

Eocky

Mountains atvery high altitudes as far south as Colo-

INSECTS.

157

rado

aDd New

Mexico. In the

White

Mountainsit is

abundant on

the

summit

of

Mount Washington

; butintheterritorybetweenthis region

and

Labrador it is

unknown,

as also between INIount

Washington and

the

Eocky

Mountains.

How

far to the northwest of the continentit flies is not

known

to me. It has not appeared in collections from Alaska, inwhich Frcya

was

representedin considerable numbers.

The

peculiar distribution of this species, C. Semidca,

by which

it inhabits^

mountain summits thousands of miles apart

and

not the intervening- country,

and

in the

White

Mountains of

New Hampshire

is thoroughly isolated

and

restricted to avery small area,is explained asin the case of plants similarly distributed

and

isolated (address of Prof. Asa.

Gray,

Dubuque,

1872).

The

advance to the southward of the glacial ice

pushed

before it multitudes of plants

and

animals, forcing

them

along verydistantlines of longitude in

many

cases;

and

wlien there- ceding of theicetookplace,

and

a mildertemperature

began

toprevail,

some

specieswhich

had

obtained a footholdatthesouthremained there,, findingaclimate in

which

they could live, ui)on lofty mountains ouly, being unable to exist in the lowlands. In the case ofthis butterfly^

such aclimate

was

found ator near the snow-Une intheEock.>' Mount- ains,

and upon

the

summits

ofthe

White

Mountains.

INSECTS.