LETTERS FROM THE SOUTHWEST.

OF WASHINGTON. 381

LETTERS FROM THE SOUTHWEST.

InsectfaunaofDasylirion wheeleri.

By H.

^G.

HUBBARD.

HOOKER'S HOT

_SPRINGS,

GALIURO MTS., AR., May

25, 1897.

The

_ridges in this vicinity arepopulated

by numerous clumps

ofDasylirion wheeleri,

many

^of

them

^killed

by

^thecattle,

which

constantly ^eat out the buds.

The young and

_{vigorousplants}

do

not

seem

to be infested

by

^{insects, but the dead}

and

_{dying plants} areinhabited

by

^{a fauna as}interesting ^{as that}of the Giant

Cac

tus,

and among them

^I recognize^a

few

_species as identical, for instance

some

of the small Histeridse

and

one of theHololeptas (ff. vicina}*

which

areextremely

abundant

in Dasylirion^{; I find} also

Trimiumpuncticolle, Eumicruslucanus, Ditoma

gracilis,

and Holoparamecus

pacificus.

The numerous

Staphylinid beetles of the Dasylirion fauna _are, however, wholly ^different from those of thefermenting

mass

of

Cereus

_giganteus,

and

be long mostly^{to the}

more

_deplanate formsof the subfamiliesAleo- charinae, Paederinae,

and

Piestinse.

The

_large

Belonuchus

_ephip- piatus^{of the} Giant Cactusisrepresented ⁱⁿDasylirion

by

^another species

(B. xanthomelas)

^,which, however, ^I find also in

decom

posing

Yucca and Agave. The

_{largeDipterous} (Volucella)^larvae

and

the Staphylinidae of the genus

Maseochara

as well as the Hydrophilidae ^{are here}wanting, but^{there are in} Dasylirion

nu merous

other species of^insects,almostallof

them

_Coleoptera

and

of small size.

All these insects live

between

the broad, flat, imbricated,

and

closely applied^leafbases ofthis

most

singularly constructedplant,

and

are dependant

upon

^the disorganization ^effected

by

a large Calandrid beetle

(Scyphophorus

acupunctatus)^, and,

more

rarely, allied species

{Yuccaborus

frontalis).

These

beetles usually enter the inside of the plant alongside the

buds

thatstart

between

theleafbases

from

the central axis.

Into the holes

made by

these Calandridsthe Hololepta

and Be

lonuchus push^their

way, and

they are

accompanied by

^thesmaller ttistevi&s^Epierusplanulatus,

Paromalusopunticz,

P.gilensis, P. _tenellus], the smaller Staphylinidae, several Tenebrionidae

(Aphanotus

parallelus, Ulosonia

marginata), and

finally a verypeculiar beetle,

which

is no doubt an undescribed Othnius.

The

small Staphylinidae of^thisfaunaareveryinteresting^;the

com monest

isa _Piestid, averitablebeauty (Piestus extimus Sharp).

It runs_activelyabout

and sweeps

^its long ^antennae from side to side likea Lasmophlreus.

Next

in interest is a small

slow-mov

ing Paederid

{Leptogenius

^n. sp.), ^its

body

being dark

umber-

brown,

velvety

and

opaque, with ^dull-red head

and

_legs.

A

^few

382 ENTOMOLOGICAL SOCIETY

specimens^ofEleusis fasciata ^also inhabit the fermenting

Da-

sylirion leaves. Finally there are several Aleocharinae, ^all

more

or less flattened, opaque, with dark coloration, the _elytra alone being^reddish.

Of

other orders Ifind the

jumping

^larvaofaPio-

phila, a peculiar Phlceotrips

and

the larvaof a small Lepidopter. ^*

Without

a careful

and

methodicaldissectionof the plant hardly anything^{ofthis rich} fauna can befound.

The bud and

the

bud

leaves

must

firstbe

removed, and

then the leavessurrounding ^the central axis of the plant ^lifted out one

by

^{one in their} regular order, beginning with ^the

uppermost

layer^{of leaves. It}takes several hour^ ^to thoroughly

examine

a large plant, but not a single insect living

between

the imbricated _layers of leaves can

make

its escape

from

thebowl-shaped cavity

between

the handles of the leaves

and

thecentral axis.

In the lower _{layers of leaves,} near the ground, ^a

number

of other beetlescreep ⁱⁿ

from

beneath but

do

not properly belong to the Dasylirion fauna: various Tenebrionidae (Arceoschizus decipiens,

A.

sulcicollis,

Emmenastus

_longulus},

Hemiptychus,

Elaterid _larvae, etc.

Underneath

the dry

clumps

^{of dead}

Dasy-

lirions

which

can beoverturned, there are the usual ^rats' and mice nests

and

_usually ^a

numerous

_colony of Eleodes.

In the dead flower stalksI see the

burrows

of a Buprestid, probablyThrincopyge, but^{flower stalks}are rare here,^as they are generally eaten ^offwhile

young and

^tender.

One

of the poles of lastyear, however, had ^a large colony ^of

Apotrepus

densicollis*

most

of the specimens being immature.

The

flowers of

Dasy

lirion attractgreat

numbers

of a

Chrysomelid

(

Triarius

trivit- tatus}

and

^small Mordellid beetles

(Pent

^{arta decolorata).}

I forgot ^to

mention

that I find constantly ⁱⁿ the central axis of dead Dasylirions a large lamellicorn larva (Phileurus Hiatus}.

Itis thislarva

which

reducesto

powder

the axis of thedead_plant, following

up

^the

work

of

Scyphophorus, which

^feedsforthe

most

partⁱⁿtheleafbases, seldom

burrowing

deeply^inthecentral core, and. never attacks the dry

and

dead _plants.

The

Phileurus larvas reducethe core

which

binds together the ^disk-like whorlsofleaf bases, so thattheentireplantcan be overturned

and

disintegrated

by

^{a fewkicks with thefoot.}

The

larva isforming ^its

pupa

^ceil

in the rotten heartof the plant^; the

pupa

has a pair of^stout horn likeelevations

upon

^{the head,}

and

isdark red in color_{; in fact,}it

resembles very

much

thatof Xyloryctes. ^{It isdifficult to}preserve the _living

pupa

^without injuryin spiteofits apparently^solid con struction.

There

is apparently anotherlarge white grub ^{in the} older stemsafter theyhave beenpartly eaten outby^{thePhileurus.}

I have not foundthe

pupa

^{ofthis,but it}

may

belong ^toListroche- lus or Phytalus.

A Longicorn larva of rather peculiar appear ance (perhaps Tragidion armatum) boresinto and through the dyingleafbasesof Dasylirion andforms pupa cellswhich resem ble those ofScyphophorus.

OF WASHINGTON. 383

This

communication was

_briefly discussed

by

Messrs. Pollard, Cockerell,

Ashmead, and Schwarz. Mr.

Pollardasked

whether

the agave

and

other large plants of^thatregionhave similarinsect fauna. Mr.

Schwarz

_replied that there are in

Mr. Hubbard's

letters various scattered observations

and

notes on the insects^liv ing ⁱⁿ or

on Yucca, Agave and

^Nolina

which

^he expects ^to gather

and

_present ^at a future time.

Agave palmer

ⁱ

seems

^to be the only Amaryllidaceous plant of southern Arizona

which when

_{perfectly healthy} is attacked

by

^{insect borers.}

These

are

two

species of the Curculionid genus

Zygops

^anda lepidopterous larva of thegenus

Megathymus.

Mr.

Cockerell stated that

two

Coccids

had

beenfound

upon

^the Dasylirion, but ^that both _species

were

also found

upon

yuccas.

Mr. Ashmead

said thatthe Dasylirion ^insects

were

_very similar in characters to the insects found in

decomposing

palmetto ⁱⁿ Florida.

The

next paper

was by Mr.

^{Marlatt,andinthe absenceof the} author

was

read

by Mr.

^{Benton. It}

was

entitled:

REMARKS ON SOME RECENT WORK ON COCCIDS.

By

^{C. L.}

MARLATT.

No group

of insects has excited

more

interest,nor attracted

more new

students perhaps ^{in the last} few_years, than the scale insects, or Coccidse. Entomological magazines, and, ⁱⁿ fact, journals of^{all sorts} anddescriptions,

and

in the

most

_unexpected

and

unusual_quarters, have been_heavilycharged with^{literature of}

new

_species, sub-species, ^etc.

The

_great

number

of such

new

species has struck the^attentionofnon-workers in thisgroup,

and

particularly hasthe designation of an astonishing percentage ^of sub-species, physiological species, varieties, etc., been calculated to arouse the gravest suspicion as ^to the reliability of the

work done and

the _validity of the forms characterized, especially

when

the characters

on which

the

new

_species, sub-species, ^etc., are based are at all

carefully investigated.

That

with all the en thusiasm manifested in

working up new

material

and

_describing

new

forms

many good

species arefound

and

characterized can not be doubted,

and

it istherefore the

more

to be _regretted that the authors responsible ^for

much good work

have been led

by

^a surplus of^{zeal to}be_guilty also of

much

that

must

be a positive detrimentto the

knowledge

^{of this}

group

^{of insects.}

For

the benefit of future students,

and

with the intention merely ^to bring about, ^ifpossible, a

much

needed reform in the interest of the