Descriptions of new species of Carboniferous invertebrate fossils

252 PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM.

DESCRIPTIOIVS OF NE%V SPECIES OF CAKBONIFEROUS INVERTE- BRATE FOSSIES.

By

C. A.

WHITE.

The

fossilshereindescribedare

among

thecollectionsofthe National Museniu.

The

coral

was

obtained

by

Prof. O. St.

John

in the Black- foot

Eange

of inonntains,

sonthward

from the Yellowstone National Park,inthe

snmmer

of 1877,wliileprosecnting- his

work

asgeologist of oneoftheparties ofthe snrvey then in chargeofDr. F.V.

Hayden.

The

spines ofArelmocidaris area part ofa small collection of

Upper

Coal

Measnre

fossils sent

by

Mr.

Frank M. Dininny

from

Tecnmseh,

Nebraska.

The

fonr species of crinoids,here described asnew, consti- tnte part ofacollection

which

hasbeenforseveralyearsinthe cases of the

Mnsenm,

the donorof

which

collection is nnfortnnately

unknown.

The

^onlylabel

accompanying

thefossils contained only the following inscription:

"From

thirty miles west of

Humboldt,

Kansas."

The

placethusindicated, asdetermined

by

a Land-Office

map,

isintheval- ley ofoneofthe upper branchesofVerdigrisRiver,atributary ofAr- kansasRiver. Besides thefour

new

species justmentioned, those enu- merated with

them

inthefollowing list constitute this interestingcol- lection:

1. PlaUjcermnebrascensis,

Meek.

2. Flnnaperacuta,

Shumard

^?

3. Terebratula millq)unctata, Hall.

4. Spirifer cameratus,INIorton.

5. Spirifer {Martinia) Uneatiis,Martin.

6. Sjriyifer[Martinia)plamconvexus^

Shumard.

7. Spiriferinal-cnfucl^oisis,

Shumard.

8. SpirigerasubfUita, Hall.

9. Eefziamormonii, Marcou.

10. Hemipronitescrassus.

Meek and Hayden.

11.

MceMIa

striatocostata,Cox.

12. Prodiictussemireticulatiis,Martin.

13. Productuspiinctatus,Martin.

11. Productuslongifiinnus, Sowerby.

15. Productusnebrascensis^

Owen.

10. Cijathaxoniadistorta,

Worthen.

17. FistuJiiwra nodulifera,

Meek.

18.

Rhombipora

lepidodendroides,

Meek.

19. Glauconome ^?

20. Lecythiocrinus olUculceformis,sp.nov.

21. Cyathocrinusstillativus, sp. nov.

22. Erisocrinustypus,

Meek and Worthen.

23. Erisocrinus planus^sp.nov.

21. Rhodocrinus resperalis, sp.nov.

Besidesthese therev/erefragmentsof threeotherspecies of crinoids

PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 253

belonging to tlie Cyafhocn'mdcv. Altliough all, or nearlyall, the cri

noidshithertopublishedfrom the

Upper

Coal

Measures

oftheUnited States,belongto the Ci/athocrinidw,the species ^o.21 of theforegoing

list isthefirst one

known

from thatformation

which

presents exactly the calycular formula of true Cyathocrinus. Besides this

two

ofthe other

new

species of crinoids belong- togenera that

have

hithertobeen

unknown

in

North American

strata

above

the Subcarbouiferous,oneof them,indeed,beingneverbefore

known

toexist.

Such

facts

demanded

rigidinquiryas to

whether

these strange forms

might

not

have

been derivedfrom

some

older formation,

and become

accidentally

mixed

with thosefromthe

Upper

Coal Measures,especially asthe

package was

not,

when

first

examined by

me,securely closed,

and

the record

was

defective as before indicated. Allthespecimens

were

therefore subjectedtocare fidexamination

under

thelens,

which

disclosedthefactthat

some

oneor

more

ofthese

new

forms

had

adheringtoitssurfacea greater orless

num-

berof

minute

fragmentsofPolyzoans,

which

were not only recognizedas

Upper

Coal

Measure

species,but fragmentsofthe

same

were foundadher- ingto

many

ofthe well-known

Upper

Coal

Measure

brachiopodsasso- ciatedwith

them

inthecollection. Inaddition tothis,the character

and

as])ectofthe

imbedding

matrix, so far asitremained withthefossils,

were

foundtobeessentiallythe

same upon

boththe

new and

well-known forms. Thereappears, therefore, tobe

no room

forreasonable

doubt

that these

new

forms, as well as the others

which

are associatedwith

them

in thecollection,

came

from

Upper

Coal

Measure

strata atthelocalityindi- cated

by

the label as beforementioned-,

and

thattheyareallfromsub- stantiallythe

same

localhorizon.

The

lossofthe recordofthedonor's

name

istoberegretted,butit

was no doubt

occasioned

by

the confusion into

which

a partofthe collectionsofthe

Museum

fell at the timeof the fire

which

a few years

ago damaged

the building ofthe Smith- sonian Institution.

The

discoveryofthese

new

crinoidalformsisnot onlyinterestingin itself,butitisimjiortant as

showing

apersistence of certain paleozoic crinoidaltypes

up

toalmost theclosingepochofPaleozoictimeasitis

represented

by North American

strata.

The

intimate relationship of at leastthe brachiopodal fauna of the Subcarbouiferous seriesoftlie MississippiValley(especiallythat of the Chester limestone

member

of that series)with thatofthe

Upper

Coal

Measure

limestone

and

shales is well

known.

Indeed, quite a

number

of the brachiopods ofthese

two

formations

we must

consider as specifically identical.

The

caseis different,however, with thecrinoidalfauuie ofthe

two

formationsasre- gardsspecificidentity, fortheyafford

no

exceptiontotheruletliatfos- silcrinoids

have

anarrowlylimited vertical range.

But

inthecase of these fossils there is

shown by

this collection to be a recurrenceof formerly existing types,or,

more

properly speaking, these

newly

dis- covered types indicate thecontinuation through preceding ei>ochs of

254 PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM.

certaing-oneric

and

family-types, tbat liave heretofore

been

discovered onlyinthe stratarepresenting the earherofthoseepochs.

Thns

Rho- docrinusvesperalis

and

CyathocrimtsstiUaiivus

have

their nearest

known

representatives in the Burlington limestone ofthe Subcarboniferons series. This is interesting because the crinoidal fiiuna ofthe

Upper

CoalIMeasures

had

hitherto presented a

good

degreeofcontrastwith corresponding faunjieofthediiferent divisions ofthe Subcarboniferons groupas well aswiththat ofthe

group

asa whole.

For

example,ashas been already mentioned,thereisa great preponderanceof the Cijatho- crinidcc inthe

Upper

^Coal

Measure

strata. Thesearemostlyof peculiar types,

and

their bodies are mostly ^also

composed

ofmassive ^pieces.

Erisocrinusispeculiar to this latest of theCarboniferousepochs, as rep- resented

by

thestrata ofthegreat Mississippi Valley,

and

it isinterest- ing-to note thatthe

new

genusLccijtMocrinusagrees withitinexcluding thewholeoftheanalseriesofitspiecesfromparticipating in thestruct- ureofthecalyx.

The

other species of crinoids

which

are

named

in the listasassoci- ated with these

new

forms bel<)ng to types, either generic or interge- neric,

which have been

hithertofound onlyin

Upper

Coal

Measure

strata.

The

spines ofthe species here described as Arcluvocidaris dininnn givea very inadequateidea ofthe characteristics ofthewliole animal,

and

such adescriptionhas very^little valuein zoologicalclassification;

butforthe convenienceof geological study^it is thought best to give systematic

names

even to such zoologically imperfectobjectsas these, thatthey

may be

used in the classificationofallthe recognizablefos- sils

which

characterize differentformations respectively.

The

species represented

by

these spines has quitea wide geological rangeinthe

Upper

Coal

Measures

ofthevalleys ofthe

Lower

Missouri

and Upper

Mississippi Eivers,

and

their characteristics aresuchthatthespecies

may be

readily recognized.

TliefullCarboniferousseriesofthe great

Eocky Mountain

regionis severalthousand feet in thickness;

and

the horizon withinthis limit, from

which

thecoral herein describedasAcervulariaadjunctivacomes,

isnotaccurately

known.

This discrepancy,however,^is apparently of lessimportance thanitotherwise

would

be,fromthe fact thatnot only

isthe greatCarboniferous series ofthat region not

marked

offinto epochal groupsinthe

same manner

thatitisin the Mississippi Valley, but it is there

everywhere

difficult to find

any

recognizable planes, either paleontological or stratigraphical, fortheseparation oftheseries into

any

well-defined groups.

PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 255

ACTIXOZOA.

Genus Aceevulaeia,

Scliweijjfger.

Acenrularia adjunctiva(sp. nov.)- Plate1, figs.1,2,and3.

Corallum massive or subdiscoidal,

composed

of compactly united corallitesof

somewhat

unequalsize; corallites approximately^straight, irregularly polygonal, averaging about live millimeters in diameter, their outer surfaces faintly

marked by

vertical lines

which

indicate the places of the septa within,but theyare not sufficientlydistinctto givea crenulatedborderto thecalyx; these surfaces alsopresent

more

orlessdistinct irregulartransversewrinklesorundulations;outerwall ofthecorallitesdistinct but not thick; inner wall well develoi)ed; di- ameterofthespace inclosed

by

the innerwall equaltoaboutone-half thefulldiameterof thecorallite; the transversetabulaeofthiscentral spacewelldeveloped,distinctlyseparate from eachother, their

number

being about ten to each centimeter oflength ofthe corallite.

The

spacebetween the outer

and

innerwallsisoccupied

by numerous more

orlesscomplete shallow infundibuliform plates,

which

arenotquite so

numerous

asthe central tabular.

These

i^lates spring

from

the inner wall,

which

theysuccessivelyhelptoform,

and

arch ui)ward

and outward

to the outerwall; being thesuccessively

abandoned

floorsofthe outer portion ofthe calyces.

They

appearto

have

been not always complete, either asregardstheirextensionto the outer wallor theirconstruction ofa symmetrical cup, but they are apparently

no more

imperfectin these respectsthanthe calyces ofsuchcoralsoftenare.

The

condition oftheonl^^specimens discoveredisnotsuchas to

show any

ofthe calyces in their natural condition,

and

the structure ofthe coralliteshasthereforebeen determined

by

theexaminationofpolished sections,bothlongitudinal

and

transverse.

While

the parts already describedare thus distinctlyshown,the rays are discoveredAvithdif- ficulty,

and

they wereevidentlyonlyslightly developed5their

number,

asnearasitcan beascertained,isabout 16or17.

The

genus Acervularia has

been

regarded as peculiarlya

Devonian

form,butas related corals are

common

toboth

Devonian and

Carbo- niferousstrata,thereappearsno

good

reason

why

Acervularia

may

not existinthelatter. This form

seems

to differ from thetypical species ofthat genus, at least tosuch an extentas

might

benaturallyexpected ofit,

when

foundinstrata of so

much

laterdatethan those

which

con- tainthe typical forms. Thisisaninteresting form,not onlyasregards

itsstructure,butalsoinconsequenceofthe

marked

difference

which

it presentsfromanj^Actinozoanyetdescribedfrom

American

Carbonifer- ous strata.

Pofiitionandlocalifj/.—Cahoniferonsstrata,Blackfoot

Eange,

southof theYellowstone National Park,

where

it

was

discovered

by

Prof.O.St.

John.

256 PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM.

ECHIXODERMATA.

Genus Lecythiocrinus

{gen.

no

v.).

Etym.At/kvOiov,asmalloilflask.

Genericformula.

—

Basal pieces, 3; subradial pieces, 5; first radial pieces, 5; aual

and

iiiterradialpieces,0.

Generic diagnosis.

— The basal, subradial,and first radial pieces are allwelldeveloped,noneofthembeing minute. The domeisnotknown, butitwas very small in comparison with the size of the body. The facet for theattachmentofthe column issmallandround,but thecol-

umn

^is not

known. The

facets for the attachment ofthe

arms

are small; the

arms

arenot

known,

but they

were

five in

number, and

evi- dentlysmall

and

delicate. Tlie character, shapes,

and arrangement

of thethreebasal pieces are precisely as in Platycrinus,

and

the arrange-

ment

ofthefivesubradial pieces

upon them

isthe

same

as that ofthe

firstradials

upon

the basals in Flatycrinns.

The arrangement

ofthe firstradiali)ieces

upon

thesubradials is essentiallythe

same

as that of Urisocrimis; thatis,theyalternate regularlywith eachother

and have no

anal or interradial pieces intervening.

The

body,

which

is the onlyportion ofthe animal yet

known,

istherefore

composed

of thirteen pieces,the

arrangement

of

which

isessentially that offive first radials, allin close contactwith eachother,superimposed

upon

the calyx-struc- ture of Platycrinus. Or,ifitbe

assumed

thatthe basal cycle of pieces inthe

body

ofeverytrue crinoid contains the elementsoffive pieces,

and

that hi case there are onlythree apparentintheadultstate,as in Actinocrinns

and many

species ofPlatijcrinns,there has been

an

early ancylosis of

two

adjacentpiecesin

two

cases,

we may

regardLecythio- crinus as a Cyathocrinid thus modified. I

am

disposedto adopt this view,

and

Itherefore refer the

new

genus to the Cyathocrinidw. Itis

thoughtto

be

not improbabletliatifother species ofthisgenus should

be

discovered the base

may

be foundto

be composed

offiveseparate piecesinstead of three,but

no

trace of a fourth

and

fifthsuturecan

be

discoveredintliebaseoftheform heredescribed. In case other

exam-

plesshouldprove to possessabase

composed

offive pie(!es,the other chara(;teristics

which

itpossesses are still sufflcient toholditasa

new

genericform

among

the Crinoidea.

Only

one

example

ofthis interesting crinoid,consistingofthe

body

alone,hasbeendiscovered. It is small

and

delicate in structure,the delicacy of the pieces com])osing it being similar to that of certain species of Platycrinus

and

Dichocrinus found in the Burlington lime- stone. Inthisrespectitdiffersfromall the hitherto

known

crinoids of the

Upper

Coal Measures, thepieces

composing

^tiiebodies ofwhichare

PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. JD

(

thick

and

often massive. This delicacyof structure is probably age- neric characteristic.

Lecythiocrinus oUiculaeformis(sp. nov.). Plate1,figs.4aud5.

Body

small,subovoidor pot-shaped,higher than broad,broadest a

little

below

the middle,

composed

ofthin pieces; base

convex

; basal pieces rathersmallbut not minute; subradial pieces largerthan

any

of the others,higher than wide, their height equaltoalittle

more

than half the full height of the body, not materially varying in size or shape; firstradial pieces smaller than the subradialsbutlargerthan thebasals,broader below thanabove,height

and

greatestbreadth about equal; at top,

on

both sides of the small prominent

arm

-facet, the borderofeachfirstradialisbent inward,constricting the alreadynar-

row

interbrachialspaceat the topof thebody,

which

space

was

prob- ably covered

by

a

dome

of

minute

pieces. Sutures not impressedor otherwise specially marked. Surface, to ordinary vision, apparently smooth, but a

good

lens

shows

ittobe veryfinelygranular.

Height,9 millimeters; breadth,7^ millimeters.

Position

and

locality.

— UpperCoalMeasurestrata,thirty mileswestof Humljoldt, Kansas. See introductory remarks.

Genus Erisocrinus, Meek and Worthen.

Erisocrinus planus(sp.nov.). Plate1,figs.6aud7.

Body

rather small, subcircular or obscurely pentahedral as

viewed

from above or below, shallow convex-basin-shaped fromthetopof the firstradials

downward

; base

somewhat

deeply impressedatthe center, the depression gradually rounding outwaril to the sides; basal pieces verysmall,occupyingthe

bottom

ofthe depressionofthe base

and

al-

most

covered

by

the firstjoint ofthe

column

; subradial pieces

mod-

eratelylarge,their inner ends bent inwardly

by

the depressionofthe baseto

meet

the small basal pieces there, their outerends extending

outward and upward

so as to be

more

or less plainly visible

by

side Anewof the

body

; firstradialpiecescomparativelylarge,

convex

verti- cally,theirupper edges rounded

inward

tothesuture

between them aud

thesecondradials,their lower angles extending

downward

almostto the lowest portion oftlie

body

visible

by

side view.

The

other charac- tersarethose

common

tothe genus.

One

minutepieceremains attached to theupper borderofthecalyxofoneof thespecimens,atthe junction of

two

ofthefirst radial pieces. This is

no doubt

an anal piece,its outer surfacebeingin the planeof the outer surface of the calyx,but

itdoes notin

any

degreeenter betwe^^nthe

two

firstradials

upon which

itrests.

Transverse diameterofthecalyx, 14 millimeters;heightofthe same, 5 millimeters.

Proc.Nat.

Mus.

79 17

Jan. 27,

1

880..

258 PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM.

This species differs

from

U.typiisin having a shallower

and more ronnded

basin-shaped calyx, proportionally smaller basal,

and

larger snbradialpieces,

and

a

more

deeplyimpressedbase. Itverycloselyre- semblesthe Poterlocrinus hemisphericus of

Shnmard,

examx)les ofwliicli areassociated withitinthecollection. Indeed,so farasthecharacter- isticsofthecalyx aloneareconcerned,there appearstobe

no

essential differenceexcept inthe relative positionofthe small anal i^iece. In Erisocrinus

no

analX)ieceisrecognizedasentering into the strnctnre of the calyx, at least

none

thatis visible

npon

the outer surface, as a greater orless

number

ofsuch pieces

do

in Cyathocrinus

and

Foterio- crinus, but I

am

^{not without} suspicion that this form

which

I have, according to the recognized usage in the limitation of genera, here describedasnew,reallybelongstothe

same

specieswithP.liemisplieri-

ciis,

Shumard, and

that the displacementofthe small anal piece

from

the rim ofthe calyx is

an

individual variation only. If this should proveto

be

the caseitisclear that arevisionofthegenericformulaof Erisocrinuswillbe necessary;

and

itwilldoubtlessalsobe necessaryto assign the typeofthis proposed species toP. hemisphericus,

Shumard.

Itiscleartbat thelast-namedspecies does not strictlybelongto either Poteriocrinusor Cyathocrinus,but it is not

my

purpose to discussthe generic relations of these forms at this time. Figure8,plate1,repre- sents

an example

ofthe P. hemisphericus of

Shumard, which

isintroduced forcomparisonwitlithoseofE.planvs.

Position

and

locality.

— Upper Coal Measures, thirty miles west of Humboldt,Kansas. See introductory remarks.

Genus Cyathocrinus,

Miller.

Cyathocrinusstillativus(sp. nov.). Plate1, figs.9and.10.

Body

belowthe

upper

borderofthefirst radial piecesshallowbasin- shaped,

much

wider than high,

having

a narrow, moderatelydeep, abrupt, five-sideddepressionatthe center of the base, atthe

bottom

of which is the facet for the attachment of the

column; composed

of eighteen moderatelythick

and

strong pieces,all ofwhich, except the basals,are

more

or less

tumid

in their middleportion,

some

of

them

I)resenting

an

irregular,

uneven

surface, which, with the imx)ressed sutures

and

thestill

more

deeplyimpressedcorners of the pieces, gives the surface of the

body

a decidedly rugose aspect; basal pieces very small,occupying the

bottom

ofthe depression at thebase,thegreater partofeach being coveredIjy thefirstjointofthe

column;

snbradial pieceshaving their height

and

width about eqnal,four of

them

pen- tagonal,

and

one, that

which

is next below the ^first analpiece,hex- agonal, therebeing

no

appreciableangle

upon

that side of

any

of

them

whi(;hadjoins the basal pieces; firstradial pieces

much

largerthan the snbradial,wider thantheirfullheightincluding the

arm

facet;the

two

PKOCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 259

wliicliareadjacentto the anal series beingverylittleif

any

narrower than the others;

arm

facets large,about one-third wider than high, their plane being nearly vertical, notched at the

upper

border

and marked

transversely

by

thedoubleridge or raisedlines

which

arecom-

mon

tothe

arm

facetsof

many

ofthe Cj/athocrinidw; anal pieces three

known,

nearlyequalin size,orthefirstalittlelargerthan the

two

second, each with a prominenttubercle atthecenter;firstanal piecefive-sided, abuttingagainstone subradial,

two

first radials

and two

second anal pieces; the

two

secondanal pieces abutagainst thefirst anal,against eachother,

and

each abutsagainstafirstradial.

Diameter

of calyx,14millimeters; heightofthesame,G millimeters.

Thisisthefirst

and

onlyspeciesoftrueCijatliocrinusthat hasto

my

knowledge

yet been discovered in

Upper

Coal

Measure

strata; G. in- flexus,Geinitz,

and

C.hemisphericns,

Shumard,

sp.,notbeing regardedas typical species of thatgenus. Itbelongs toa type that is

more

char- acteristicoftheBurlington limestonedivisionof theSubcarboniferous thanof

any

other division of the great Carboniferous series,

and

to- gether with the next described formit

shows

thecrinoidalfaunaof the

Upper

Coal

Measures

tobe

more

intimately related tothatoftheSub- carboniferousthanithasbeforebeen

known

tobe.

Position

and

locality.

— UpperCoalMeasurestrata,thirty mileswest ofHumboldt,Kansas. See introductory remarks.

Genus Ehodgcrinus,

Miller.

Rliodocriiius vesperalis(sp. uov.). Plate1, figs.11and19.

Body

subglobose,thesides

and

outer portion of thebase continuously

convex

; the base

having

adeep, sharjily defined, five-sided pitwhich contains the wholeofthe five basal pieces,

and

also the sharply in- flexedinnerendsofthefive subradial pieces; the latterpiecesmoder- ately large,but not

much

larger than

some

ofthe radials

and

inter- radials; firstradial piecesvarying alittle in sizeinthedifferent rays, the largerones nearlyor quite aslarge asthesubradial; secondradials

much

smaller than thefirst,

and

thethird radials still

much

smaller thanthe second,the difference in size being greater in their A^ertical thanintheirtransverse diameter.

The

third radial ineachray,

which

isvery

narrow

vertically,supports

two

brachial pieces,

and

theyinturn each support anotherbrachial piece,

beyond which

thestructureisun-

known

; interradialpieces

up

toalinewith thecenter ofthe

arm

bases, three for four of the interradial spaces,

and

four for that ofthe anal

.

side; the firstorlower interradials are ofabout equal size ineachof the spaces,

and

alittlelarger than the

two

next

above

;

dome

moder- atelyconvex,prominentopposite the

arms and somewhat

depressedbe-

tween

them,

composed

of

numerous

smallpieces; proboscis subcentral, itslength

unknown.

All the iDiecesofthe body, except thoseof the

260 PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM.

base,aresliglitlytumid,theirsurfacesbeing rugoseorwrinkled,

and

in

some

ifnot all cases

marked by

obscurelines

which

radiatefrom the center ofeachpiece in groupsof threes,

and become

continuouswith similarlines

on

adjoiningpieces.

Height

from the baseofthe

body

to the baseof the proboscis,32 millimeters; breadthofthesame, ]6 millimeters.

Although

thisspecies serves asavery suggestive link

between

the crinoidalfaunaofthe

Upper

Coal

Measures and

that oftheSubcarbo- niferous, especially that ofthe Burlington limestone division ofthat series,itdifferstoo

much

specificallyfrom

any

describedform

embraced by

thatgenustoneeddetailedcomparisons.

Position

and

locality.

— UpperCoalMeasure,thirtymileswestofHum-

boldt,Kansas. See introductory remarks.

Genus Aech^ocidaeis, McCoy.

Archaeocidarisdininnii. Plate1, figs.I'.i,14,and15.

Principal spines fusiform, moderately strong, 50 or 60 millimeters long, the greatest diameter being about the middle,

which

is there about5 millimeters.

The

diameterofthebasal ring ofsuch a specimen isabout 3Jmillimeters,

and

the short neck or j^lain space

above

itis scarcely2i millimeters in thickness.

Above

the short plain

neck

the wholespineisstudded withirregularlydisposedspinules, 1 to 2 millime- tersinlength,

which

stand outatnearlyrightangleswith theaxis ofthe spine,exceptnearitspoint,

where

they are directedupward.

The

spi- nulesareusually

more numerous and

stronger

upon

thelowerportion of the spine than elsewhere,

and upon

the middle portion ofthe large spinesthey are sometimes obsolete,apparentlyfrom

some

othercause thanaccidentalremoval.

The

smaller spines are often notso thickly studded with spinules as the larger ones,

and

theyare usually

more

slender or less fusiform than the larger;

and some

of

them seem

to

have

been without abasalring.

A marked

peculiarity ofthis species is the

abundance

of spinules

upon

the spine, especiallyitslowerportion,

and

the general positionof

most

of

them

atnearlyrightanglestoitsaxis.

Positionaiid locality.

—

^{Uj^per}Coal Measures, near

Tecumseh,

Nebras- ka,

whence

it

was

sent with other

Upper

Coal

Measure

fossils

by

Mr.

Frank M.

Dininny,in

whose

honor the specific

name

is given. This specieshas also been recognized

by me

^inrocksof that formationiu other portions of

Nebraska and

also in

Western

Iowa.

.

Washington, Novemher

8,1879.

EXPLANATION OF PLATE

1.

ACERVULARIAADJUNCTIVA.

Fig.1,iismallclusterofcorallites,naturalsize. Fig.2,transversf shcuouof the Bime. Fig.3,verticalsectionof a singlecorallite.

LECYTHIOCRINUS OLLICUL^FORMIS.

/

Fig.4,.'ideviewofbodyenlarged to 1^ diameters. Fig.o,diagramofthesame,in thesameproportions.

ERISOCRINUS PLANUS.

Fig.(i,bawalviewof body, uatnralsize. Fig.7,viewofoval sideof the .same.

Fig.8,similarviewof thePoieriocrimishemisphericusShnmard,forcomparLsou.

CYATHOCRINUSSTILI.ATIVUS.

^ Fig.9,sideviewof calyx,naturalsize. Fig.10,basalviewof thesame.

UIIODOCRINUSVESPERAXIS.

*'Fig.11,sideviewofthe body, naturalsize. Fig.\2',basalviewofthes;aue.

ARCH^OCIDARISDLNINNII.

•^ Figs, 13, 14,and15,viewsofdifferentspines.

Proceedings Nat. Mu8.,1879. C.A. White. Plate 1.

^-,

^\^-

1,2,and^3.

—

Acf.rvularia adjunctiva.

1and^.5.—Lkcythiocrixusollicul^fokmis.

fland 7.—Erisockinus planus.

S.—POTERIOCRINUSHEMISPHF.RICU8.

9and:0.

—

Cyathocrinusstillativus.

11and12

—

Rhodocrinusvesperalis.

13, 14,and15.—Arch^Ocidarisbininnii.