Proceedings of the United States National Museum

1886.]

PROCEEDINGS OF UNITED

bTATEiS

NATIONAL MUSEUM. 547

DESCRIPTIONS OP TEN SPECIES AND ONE NEW GENUS OF AN- NELIDS PROM THE DREDGINGS OP THE

U.S.

PISH COMMISSION STEAMER ALBATROSS.

ByJTAITIES £.

BKIVEDICT.

(Withsix plates.

)

SEEPULID^.

The

tenspeciesdescribedin thispaper werecollectedontheAlbatross expeditionsduring theyears 1883-'85. Five are well

known, and

five are believedtobe new. Other speciesof the familyin the collection remain tobe described inanother paper. ^"

The

Serpulidse are not

among

the easiest annelids to collect.

The

tubes are nearlyalwaysattachedto deadshells

and

stones, which from theirnature arelikely to beleft to thelast for preservation,

and

then, if the tubes are notbroken with

much

care, the inhabitants arelikely tobe badly mutilated, while as a rule those left in the tubes are not wellpreserved. Altogether there is no family of animals

more

likely tobeneglectedin dredging,

when more

showy,

and

apparently

more

delicate,forms areabundant.

'»

Peotula

^Eisso.

Protula diomedese, ^{n. sp.}

(PlateXX, figs.1-6.)

The

branchial filaments are inserted

on

a spiral of about1^turns,

and

are about40 innumber. Eye-like spotsareexposedtoview

when

the branchiae are detached.

The

thoraciclamellaeare broad

and

thin, withentireedges.

The

thoracic setaeare long

and

slender, outer third limbate(fig. 3).

The

uncini of this region are shorter

and

broader than those of the

abdomen

(figs. 1

and

2).

The

anteriorabdominal setae are short, with broad, flat,

and

slightly falcateblades.

The

inner edges of the blades areserrate(fig. 4).

The

extremeposteriorabdominalsetae,asis

common

in speciesofthisgenus, arevery long

and

hair-like,withcurvedpoints.

The

tubes(fig. 6) arefrom 4 to 5 inches in length,

and

are attached

by

the base to objects on the bottom.

The

lines of growth are not conspicuous.

The

surface is very rough to the touch, reminding one of shark skin.

The

average length of specimens in alcohol is 40°i""; breadth, 3™™.

Length

of thorax,^11°»™; from collar to

end

of branchiae, 10"^'".

Dredged

ⁱⁿ great

numbers

at station 2307, in 43 fathoms, off

Cape

Hatteras;

and

one or

two

at atime atother stations.

548 DESCRIPTIONS OF

ANNELIDS.

RECORD OF SPECIMENS.

Off the eastern coast of the UnitedStates

:

Latitude 36°^38'30"N.,longitude 74°^40'10"W., 81 fathoms; station 2011, one specimen(981).

Latitude 36°^41'05"N., longitude 74°^38'55"W., 373fathoms; station 2014,two specimens(982).

Latitude 39°^29'00"N., longitude 72° ^19'55"W., 74 fathoms; station 2031,two specimens(983).

Latitude^{39°29' 00"N.,} longitude 72°^19'40"W., 74 fathoms; station 2032, one specimen(984).

Latitude^{42°32'00"N.,} longitude 68°^17'00"W., 99^ fathoms; station 2055,one specimen(985).

Latitude^{40°16'50"N.,longitude(i7°05'15"}W., 1,290fathoms; station 2084,one specimen (980).

Latitude 40°^05'00"_N., longitude 70°^34'45"W., 70 fathoms; station 2085, one specimen(987).

Latitude 40°^05'05"_N.. longitude 70°^35'00"W., 69 fathoms; station 2086, one specimen(988).

Latitude^{40°06'50"N.,}longitude 70°^34' 15"W.,65 fathoms; station 2087, two specimens(989).

Latitude^40°01'50"N., longitude 70°^59'00"W.,117fathoms; station 2091,one specimen(990).

Latitude^39°57'30"N., longitude 69°^41'10"W., 78 fathoms; station 2199, one specimen(991).

Latitude^{35°42'00"N.,}longitude 74°^54'30"W.,43 fathoms; station 2307,very numerous(992).

Latitude^37°08'30"N., longitude 74°^33'30" W.,85 fathoms; station 2422, two specimens(994).

Latitude^{44°27'30"N.,}longitude 57°^10'45"W.,137 fathoms; station 2472,two specimens(995).

Latitude^{44°07'30"N.,}longitude 57°^16'45"W.,116 fathoms; station 2481, one specimen(996).

GulfofMexico:

Latitude^{28°36'00"N.,}longitude 85°^33'30"W.,

HI

fathoms; station 2402, two specimens(993).

Two

^{speciesof Protula}

^have

^{already been describedfrom} practically the

same

^{region, P.media} Stirapson,*

and

P.americana Mclntosh.t

From

these P. diomedece ^{is readily} distinguished,^livingas itdoes in

a comparatively ^straight tube attached only at the base, while they both ^{construct coil}tubes attached

more

or lessthroughout their entire length.

A much ^more

important difference in the case of ^P. mediais itsdeeply scalloped^lamella?described

by

Stirapson

and

figuredinSmith

and

Harger's Saint George's

Banks

Predgiugs, i)l.vi,as

compared

with theentire margin of the thoracic lamelUe of P. diomedew. In the case of Protulaamericanathe uncini are very^different.

Compare

^fig.2 with

fig. 7of Mcintosh.

*MarineInvert., Grand Manan,p. 30,1853.

tChallenger Reports, ^vol.12, p. 512,pi. liv, fig.3; ^pi.xxxia,figs.19and20_; 1885.

1886.]

PROCEEDINGS OF

ttNITED

STATES NATIONAL MUSEUM. 549

Protulaalba, n.sp.

(Plate xs,figs. 8,9.)

Branchiaespiralofaboutoneturn; filaments, twenty-five.

When

the branchiseare

removed

atthebasetwo dark spots are exposedto view, as described

by

Stimpsonas a character^ofP. media.

The

thoracic lamellae are broad

and

verythin, continuous with the collar, which is entire.

The

setae of the thorax are long

and

slender, outer third limbate.

The

uncini of the thorax and

abdomen

are alike inform; theirteethare exceedingly minute (fig. 8).

The

falcate setaeofthe

abdomen

havealso veryminuteteethon theirinner edges (fig. 9).

The

extremejjosterior

abdominal setaeare ofthe usual form,long,hair-like, and curvedatthe ends. Colorwhite.

Length

of largespecimens^25™'"; breadth ofthorax,includinglamellae, gmm. breadth of

abdomen

2.5™'".

Saint

Thomas, West

Indies; shallow water.

Ten

specimens(979).

Hydroides

Gunner.

HydroidesdianthusVerrill.

(Plate XX,fig. 10.)

Serpula dianthusVerrill, Invert.AnimalsofVineyai'clSound,p.620, 1874.

Hydroides dianthusVerrill, Proc. Acad. Nat. Sci.,Phila., for 1878,p. 300.

Hydroides dianthusWebster, Auuel. Chajt. of the Virginian Coast, p. 06, 1879; and Annel.Chset. of

New

Jersey, p. 28, 1879.

The

branchiae are comi>osed of about eighteen filaments. There are three concentriccircles ofspineson theoperculum,the outeronebeing-

formed

by

thedenticles onthe edge. Thesedenticles are from21to27 in number, short

and

pointed, curving outward from the center.

The

next circleis

composed

of tenlong spines (tenon four specimens

and

nine on one), curvingeither outward from the center ortowardsit; in none of the specimens

examined

did

more

than five point outward.

The

^third

and

inner circle is

composed

of short conical projections arisingfromthebase of the long spines of the secondcircle (fig. 10);

these conical projections or spines are close

down

to thetloorof the operculum,

and

are usually concealed

by

dirt.

The

onlycolorremainingisa wide

band

of dark green alittle below theedgeof the operculum.

Tubes

convoluted,calcareous, on living oysters, shells,

and

stones.

Five smallspecimens from the oyster beds of

Chesapeake Bay

(997).

Hydroidesspongicola,n.sp.

(PlateXX,figs. 11, 12. Platexxi,figs,13-16.)

Branchiae large, composed of aboutthirty slender filaments.

Operculum armed

with three concentric circles of spines, the outer one on the edgeofthe operculum comprisingsixty-five slender-pointed denticles curving outward fromthe center.

The

next

and

most ]>romi-

nent ^circle arises from inside the cup of the operciilnm and extends

upward

perpendicularly to thefloor; it is

composed

offrom fourteen to

550 DESCRIPTIONS OF ANNELIDS.

eighteen spines, their points curving invariablyinward^(iig. 12).

The

innercircle of spinesarisesfrom the base of the long spines, nearthe bottomof the cup,

and

ai'eslightly curved towards the center (fig. 11).

The

collar- setae

have two

conicalpointsatthe

head

of the

main

shaft (13).

The

uncini of thethorax have from six to eightteeth; those of the

abdomen

aresmaller,withthe

same number

ofteeth(figs.14

and

15).

The

setse

and

uncini of this

and

the preceding speciesare so nearly alikethattheyfail tobe characteristic.

Very

thin

and

frailcalcareous tubes in livingsponges.

Lengthof large specimen, ^40'°'»; breadth, 2.5"*°'.

Gulf of Mexico, latitude 27° 04' N., longitude 83° ^{21' 15''} W., 26 fathoms; station 2409, ten specimens (975).

Hydroidesprotulicola, n. sp.

(Plate XX,^tijr.17. Platexxi,figs. 18-23.)

The

branchiae are small, having from ten to twelve filaments with long,

naked

ends; the pinnae arelarge.

The

operculahave about twenty six conical pointsformingthe edge.

Twelve

stout spines, with their points invariablybent outward from the center, form the inner

and

prominent armature (fig. 18). These spines

have

stout,decurved processes ontheir innerbases, correspond- ing to the spines forming the iniier circle in the preceding species (fig. 17).

As compared

with

H.

diantJms,the points at the

head

of the

main

shaft are a little Irmger

and

not quite so stout,

and

have prominent markings below

them

(fig. 19).

The

thoracic uncini, having from six to eight teeth, are

much

nar- rower than the abdominal, which havefive or sixteeth(figs.20

and

21).

Found

livingincoiledtubes fastenedtothe tubes of Protula diomedew.

Lengthof large specimens, 16™™; width, 2™™.

Off

Cape

Hatteras,latitude 35°42'N., longitude 74°54' 30" W., 43 fathoms; station 2307, 20 specimens (972).

Crucigeea, new

gen.

Serpulidse with the operculum infundibuliform

and

calcareo-carti-

,

laginous, bearing radii

more

or less branched, Avith rounded apices crenulating the periphery; inner surfaces beset with conical teeth.

Peduncle withfourdigital processes justbelowthe operculum, forming across.

Crucigera"Websteri,n.sp.

(Platexxi,figs.24,25. Platexxii,figs.26-30.

>

The

branchiae are

composed

of about eighteenfilaments.

The

operculum is bell-shaped, with a strong peduncle; four digital processes arise on the peduncle ^just belowthe cup

and

form across.

The

diskis

composed

ofa

number

^ofradii,branching soas to formfifty well rounded apices (ligs. 24

and

25).

The

radii, on their inner sur- faces,are

armed

with sliort, conical, horny teeth.

1886.]

PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 551 The

collar-setseare loug

aud

very stout (figs. 26

and

27).

The

thoracic uncini are like tlie abdominal, but

much

larger(figs.

29 and 30).

The

tubes, on^theirupper surfaces, have

two

or three veryirregular, thin ridges; theirunder ^surfaces,usually attached^forthe greater part of ^their"length to

dead

shells

and

stones, are,

when

^{free, round}

^and

smooth.

Length of large specimen, 16°"".

Gulf of Mexico, ^latitude 29° 16' 30" N., longitude 85° ^32'

W.,

26 fathoms; station 2369, eight specimens (974).

PoMATOSTEGUS

^Schmarda.

Pomatostegus^{stellatusSchmarda.}

(Platexsii,figs. 32-35. Plate^xxiii, figs.36,37.) TerciellastellataAbilclg., ScliriftenNatnrf.,Freunde,ix,p. 142.

SerpulastellataSavigny,Syst. des Ann.,p.^7.5.

Pomatostegus^stellatusSchmarda, Neuewirbellose Thiere,p. 32,1859. .

The

opercula

have

from

two

tofive disks,theupperones often

much worn aud

broken, those nearest the peduncle usually quite ^perfect.

The

^upper disks are readily detached, leaving the projectingstem of the one below

surmounted by

the usualcrown of radial points.

The

specimens show,ⁱⁿ

some

^{cases,apartialcleavageofthesoft headofthe} peduncle fromthe lowest disk^{(figs.32-34). It} would appear from^this that the disks were successively ^secreted,

and

that they

grow

out, keepingtheoperculum in good repair.

The

coUar-setJB are long and slender, slightly constricted,

and

then enlargedjust below thehead of the

main

shaft (fig. 35).

The

thoracic setfe arelimbate; the uncini are large

and have

twelve or thirteen teeth (fig. 36).

The

^{abdominal uncini are the}

same

ⁱⁿ shape, but have ^{only nineorten teeth (fig. 37).}

The

branchite^{are spiral,}of little

more

than one^turn.

They

retain their color in alcohol, varying from a dark^blue, with ^onlya traceof white, to a blue with white bands.

One

specimen has white^branchiae with only verynarrow

bands

of blue.

Length

^oflarge specimens, 45™"; width, ^{4'°'^.}

Ten

specimens⁽⁹⁶⁹

and

998).

Jamaica

and

Curasao^; shallow water.

Spirobranchus

Blainville.

Spiiobranchus ^{giganteus (Pall.)Morch.}

(Platexxiii,figs.38-42. Plate xxiv, ^figs.43-47.) Serpulagigantea Pallas,Misc.Zool.,p. 139,pi. 10, figs.2-10.

SerpulagiganteaSavigny, Syst.des Ann., p.^74.

SerpulagiganteaGrube, Fam. dor Auu., p. 90.

Cymospira giganteaBlainville, Diet, desSci.Nat., Art. Vers.

Cymospira^giganteaSchmarda, Nenewir'.jelloseThiere,p. 31.

CymospiragiganteaQnatrefages,Hist.Nat. des Ann.,tomo^ii, p.543.

SpiroiranchuagiganteusMorch, Rev.Crit. Serp.,p. 56,pi.ii, figs.18-20.

552 DESCRIPTIONS OF

ANNELIDS.

There are eight specimensof thisspeciesin the collect iou, fourfrom

St.

Thomas and

four from Cura9ao.

The

St.

Thomas

specimens are

somewhat

darker

and

smallerthanthosefromCura9ao.

The

operculum of a small specimen from St.

Thomas

is nearly circular (fig. 38).

A

slightly largerspecimen shows aridgerunning back from the horns to the center of the^disk, as isthe case with specimens of the

same

size

from Cura9ao.

Figs.41

and

42

show

an operculumofa largespecimenfromCura9ao, in which the ridge runs

back

to the posterior edge of the disk

and

is elevated, having fourshorthorus projectingat the end.

The

branchiae of the large specimens areeight-spiral; those of the small,five-spiral.

The

collar-setai are of

two

varieties (figs. 43

and

44).

The

points of setse represented

by

fig.43 wereinvariably broken.

The

figure shows the point restored

by

i>roducing theoutlines to an intersection

beyond

the break.

The

thoracic uucini^(fig.45)

have

fromsixteen to eighteen teeth; the abdominal (fig. 46), from ten to thirteen.

The

collarsofallthe specimensare of a deepblue^; the branchiae are rose-red, variegated withflesh-color.

As

is well

known,

this species lives in tubesformedin coral.

The mouths

of the tubes are

made smooth by

a secretion of carbonate of lime of alight-purple tinge.

A

^single curved spine of the

same

sub- stanceprojectsover the entrance of thetube^(fig. 40). Thisisundoubt- edly secreted

by

the

worm.

The

largest specimen is about TS'""'in length

and 9™™

in breadth

;

the smallestabout 40™™ inlength,

and 5™™

inbreadth.

Colors

and

sizes taken from specimensin strongalcohol.

Coralreefs; shallow water (961-964).

Spirobranchusincrassatus(Kroyer)Morch.

(Platexxiii. fig.48. Plate xxiv,fig.49.) CymospiraincraasataKroyer, Mus. Reg.

Cyviospira incrassataQuatrefages,Hist. Nat. tiesAnu.,t. ii,p. 545.

Spirobranchusincrassatus Miirch, Rev.Grit.Serp., p. 59, pi. xi, ligs.21-23.

A

^{single specimen of this species}

was

placedin the collection

by

a

member

ofthe

Mexican

GeographicalCommission. Itagreesquitewell with Month's description

and

figures, except that the unpaired horn arisesfrom the operculum ^(fig. 49) at the

same

angle as the large pair,

and

allare

much

nearer thecenter.

The

trueoutlineof the opercuhim

is

shown

in fig.4S.

The

branchiaeare eight-spiral.

Itis probable thatalarge seriesof specimens would

show

this to be a variety ofS. (jiganteus^or even aform due to age.

The

species

was

describedoriginally from thePacific Ocean.

The

longcollar-setoeare the

same

ⁱⁿ size

and

shape as those figured from *S'. giganteus. It

was

impossibleto com^jarethe small collar-setaj.

183G._]

PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 563 The

thoracicuuciui have fromeighteen to twentyteeth; theabdom-

inal, eleven to thirteen.

The

capillary setae from the

abdomen

are a

little

more

enlarged atthe end.

Length, OO""™; breadth, 0'"'", in alcoholic specimens.

No

color re-

mains.

Collected at

Vera

Cruz. Teste SeiiorJ. G. Aguilera(999).

SpirobranchusdendropomaMorcli.

(Plate xxiv, figs. 57, 58. Platexxv, figs.50-56.) Spirobranchusdendropoma Morcb, Rev. Crit.Serp., j*.60, 1863.

Cijmospira litigeraQuatrefages,Hist.Nat. desAnn.,tomeii,p.545, 1865.

Many

specimensofthisspecieswerecollected atSt.Thomas,Jamaica,

and

Curagao. They-agree quite well with Morch's description except that the horns, five or six in number, aresituated nearer the center than hedescribesthem.

The

branchiae^differ from the

two

precedingspecies of the genusin having but oneturn ona circular ratherthan on aspiral base,

and

in the structureofthe branchialfilaments, which haveacirrus atthebase ofthe free portion (fig. 50).

While

inthese respectsitdiffersfromtheleadingspeciesof the genus, the structure of the opercula

and

the form ofthesetoe

and

unciui

show

itto be closely related toit.

The

operculavaryin shape,

and

rangein colorfrom darkblue to white.

The

horns of

some

of the largerspeci-

mens

^(fig. 53) are short

and

stumpy, while others are long

and

have

numerous

branches(figs.51

and

52). Specimenswithlargehornshave, asarule,

more

slender peduncles.

The

digitalprocesses onthe inner marginofthe wings ofthe peduncles are often wellmarked.

No

unbroken specimensofthecollar-setjewerefound.

The

markings onthehead of themain shaft are

more

distinct than those on similar setae ofS. giganteus^(fig. 54.)

The

uncini of the thorax are similar to those of the

abdomen

but larger,

and

average one or

two

teeth more, the former having from twelve to fifteen,

and

thelatterfromten to thirteen, accordingto their position in the

row

(figs.55

and

56).

The

abdominal ^setae arescarcely distinguishablefrom those oftheprecedingspecies (fig.57).

The

specimens

when

firstcollectedwere placedin strongalcohol,

and

stillretain

some

color,asisoftenthe caseunderthese circumstances.

The

branchiaevary from a light toa dark blue

banded

with white.

The

lamellaeof the thorax are in most casesa dark violet-blue.

The

thorax

and

anteriorpart of the

abdomen

are dark.

Length

oflargespecimens, 40"""; breadth, ^2.5™™.

In tubes5 coralreefs; shallow water (967, 968,

and

977).

PEOCEEDINGS OF UNITED STATES NATIONAL MUSEUM.

[1686

EXPLANATION OF PLATE

^XX.

ProtuladiomedeceBenedict,ep.nov.

Fig. ^1. Thoracicuncinus,enlarged650 diameters.

Fig.2. Abdominaluncinus, enlarged 650 diameters.

Fig.3. Longthoracicsetae,enlarged 433 diameters.

Fig.^4. Anteriorabdominalsetae,enlarged 433 diameters.

Fig.5. Posteriorabdominalsetae,enlarged 433 diameters.

Fig.6. Tube,naturalsize.

Protula americanaMcintosh.

Fig.^7. Anterior uncinus,afterMcintosh,enlarged 700 diameters.

Protula alba Benedict,^sp.nov.

Fig.8. Abdominaluncinus,enlarged 650 diameters.

Fig.9. Anteriorabdominalsette,enlarged 433 diameters.

Sydroides dianthua ^Verrill.

Fig.10.Spineofoperculum,showingconicalprocessat base,enlarged43diameters.

HydroidesspongicolaBenedict,sp.nov.

Fig. 11. Spine ofoperculum,enlarged 43 diameters.

Fig. 12. Operculum,enlarged.

SydroidesprotulicolaBenedict, sp.nov.

Fig.17. Largespine ofoperculum,showing protuberance oninnerbase,enlarged 43 diameters.

ProceedingsNat.Miis.,Vol.IX,18SG.

—

Benedict

7

PLATE XX.

PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM.

^[1881

EXPLANATION OF PLATE XXL

HydroidesspongicolaBenedict,sp.nov.

Fig.13. Collarsetae,enlarged 325 diameters.

Fig.14. Abdominaluncinus,enlarged 650 diameters.

Fig.15. Thoracic uncinus, enlarged 650 diameters.

Fig.16. Spatulatesetfeofabdomen, enlarged 325 diameters.

HydroidesprotulicolaBenedict, sp.nov.

Fig.18. Operculum, enlarged.

Fig.19. Collarsetae,enlarged 210 diameters.

Fig.20. Thoracic unciuus, enlarged 650 diameters.

Fig.21. Abdominaluncinus, enlarged 650diameters.

Fig.22. Spatulatesetfe,enlarged 325 diameters.

Fig.23. Outline ofcollar, enlarged 37 diameters.

Crucifera Wtbsteri,Benedictsp.nov.

Fig.24. Diskofoperculum,enlarged.

Fia.25. Radii, enlarged.

ProceeflinjrsKat. Mus.,Vol. IX, 1886.—I'.emilict.

PLATE

XXI.

PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM.

[1886

/

EXPLANATION OF PLATE XXn.

Crucifera WeisieriBenedict,sp.nov.

Fig.26. Collarsetae,frontview,enlarged 210 diameters.

Fig.27. Collarsetss, sideview,enlarged210 diameters.

Fig.28. Spatulatesetaj,enlarged 325 diameters.

Fig.29. Thoracicuucinus,enlarged 650 diameters.

Fig.30. Abdominaluucinus,enlarged650diameters.

PomatostegusstellatusSchmarda.

Fig.32. Operculum andpeduncle, enlarged.

Fig.33. Stellateendsof opercula, enlarged.

Fig.34. Lowerdisk ofoperculum,enlarged.

Fig.35. Collarsetas,enlarged 210 diameters.

Pro<eedin}:8 Xat.Mus..Vol.IX. 1886.—Benedict.

PLATE

XXII.

PROCEEDING OP DOTTED STATES

NATIOIJAL

MUSEUM.

[1886.

EXPLANATION OF PLATE XXUL

Pomato8tegii8'8teUatu8Schmarda.

Fig.36. Thoracicuncinus,enlarged 650 diameters.

Fig.37. Abdominaluucinus, enlarged 650 diameters.

Spirohranchus giganteus(Pall.)Morch.

Fig.38. Trueoutline ofdiskofoperculum,smallspecimen, enlarged 5 diameters.

Fig.39. Trueoutlineof disk ofoperculum, large specimen,enlarged5 diameters.

Fig.40. Mouthof tube,enlarged 3 diameters.

Fig.41. Operculum,frontview, enlarged.

Fig.42. Operculum,sideview, enlarged.

Spirobranchusincrassatua(Kroyer)Morch.

Fig.48. Trueoutlineofoperculum,enlarged5diameters.

Proceediugs Nat.^Mils.,Vol.IX,1886.

—

Benedict.

PLATE

XXIII.

PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM.

[1886.

EXPLANATION OP PLATE

XXIV.

SpiroirancJiusgiganteus (Pall.)Morch.

Fig.4:^. Straightcollarsetae,enlarged210 diameters.

Fig.44. Bentcollarsetae,enlarged 210 diameters.

Fig.45. Thoracic uncinus, enlarged 650 diameters.

Fig.46. Abdominaluncinus, enlarged 650 diameters.

Fig.47. Abdominals&tai,enlarged 325 diameters.

Spirobranchusincrassatiis(Kroyer)Morch.

Fig.49. Operculum,enlarged.

Spirobranchusdendropoma Morch.

Fig.57. Abdominalsetae,enlarged 325diameters Fig.58. Thoracicsetae,enlarged325 diameters.

Proceedings Nat. Mus.,Vol.IX, 1886.—Benedict.

PLATE XXIV.

PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM.

^LIH-O.

EXPLANATION OF PLATE

XXV.

Spirobranchus denilropomaMorch.

Fig.50. Portionofbrancliial iilamcnt, eularged.

Fig.51. Operculum,frontview, eularged.

Fig.5'2. Operculum,sideview, eularged.

Fig.53. Operculumof a large specimen, enlarged.

Fig.54. Collarsetue,enlarged(>50diameters.

Fig.55. Thoracic uncinua, eularged 050 diameters.

Fig.5(>. Abdominaluuciuus,eulixrgedG50 diameters.

Pri.ceediugs Nat.Mas.,Vol.IX,1886

—

lii-iieilict.

PLATE XXV.