Observations on the Pterylosis of certain <I>Picido</I>

Correspondence. [April

CORRESPONDENCE.

\Correspondeiitsare requestedtowritebrieflyandtothepoint.

No

attentionwill bepaidtoanonymouscom7nunications.~\

ObservationsonthePterylosis ofCertainPicidae.

To THE Editors

of

The Auk

^:

—

Dear

Sirs:

— On

the25thoflastAugust,'Forestand Stream'verykindly publishedacontributionofmineentitled 'A Chapter onPterylography,' whichwasillustratedbylivefigures. That paper pretendedtobe nothing

more

thana good guide to those interested in pterylography,and

who

desiredto

know

somethingofoneof the best characters

we

find inbirdsto assistusintheir classification. It wasalso written with the hopethat those

who

hadtheopportunity might

more

carefullyexamine into this character

among

our

own

birds,and in time be enabled to

make some

useful contributionstothe subject.

In the 'Chapter' Irefer to,

my

chiefexamples were chosen from the Woodpeckers, andinthecourse of

my

demonstrationsof theapteriaand pterylcB,asfound

among

certainforms of thosebirds,a

number

ofinter- estingand importantfacts

came

to light. Since then, I have carefully examinedthepterj'losisinthegenusColaftes.,andcompareditwithaddi- tional specimens ofDryobates and Sphyrapicus.

Had

Ibeen ready to pluck certain tempting specimens fromthePacificcoast region,whichI

haveby

me

inalcohol,andforwhichI

am

undergreat obligationstoMr.

G. Frean

Morcom

ofChicago, and Mr.F. StephensofSan Diego,Cal., Imight have thrown perhapsstill

more

light

upon

thissubject,butthese specimensI

am

reservingfora future and

more

extended

memoir upon

thePici.

At

anyrateIwouldlike to reviewin thepresentconnection

some

of

my

observations

upon

the pterylosisof the

American

Picidre,and bring thefacts in question

more

directlytothe notice ofworkingornith- ologists.

Nitzschinhis classical

volume

on 'Pterylography' (English Trans.) confesses to have beenable to examine only afew species of

Wood-

peckers, so hisaccount of the pterylosisinthisgroupof birdsisnot as fullasitmightotherwisehavebeen. Hisinvestigationswere apparently confined to Picas luridus (a speciesofSumatran Woodpecker, first describedby him,andwhichlacked thesmall "innerhumeraltract"),P.

tridactylus, P. carolitttis, P. beuffalensis, P. auratw^, P. medius, P.

macei,P. martins, togetherwith Picumtius7ni?iutus,and

Yunx

torquilla.

Inhisdescriptionsof the pterylosisin Pici, thiseminentobservercalls attention to the submedian, longitudinal capital apterium, extending along the elevation caused by the underlying limbs of the prolonged hyoidean apparatus. This is

shown

at b, c,inFig. 2 of the present letter.

iSSS.] Correspondence.

213

Figurei.

—

Leftlateralview of aplucked specimenof Harris'sWoodpecker{D.v.

karrisii),ad.c?, lifesize,bythe author,fromthespecimen;d,upperpart of the'infe- riorspace" {Apt. mesogastrxl); k,theuropygialglandof theleftside;/,itsexternal papilla withopeningatitssummit,whichisalsotufted.

Nitzsch says ofit,that

"On

thehead the vertical space is especially remarkable, abanddestituteof contour-feathersextending fromthebase of the beak, over the foreheadtothe occiput,which I find in all

Wood-

peckers" (p. 96).

As

Ihavealready

shown

in

my

'Forestand Stream' article, and here reproduced inFig. 5,this feature is totallyabsentin

21 A. Correapoudence. [April

Splivrapicus v. niichalis^anditisawell-known factthat inthis

Wood-

pecker the limbs of thehj'oidarches are nearly or quite as short as

we

find

them

inordinarybirds.

Another apterium, also alluded to by Nitzsch,and occurring on the sidesof the head,^isthetemporalspace;thissmall, subcircular,nakedarea,

when

present,isfoundjustbehindtheeyeand above the aperture of the 'iar. Itwasnotobservedby

me

inthespecimen of Harris's

Woodpecker shown

inFig.i,butrecentand

more

extended observations lead

me

to believe thatitisaquite constant pterylographic characterinthis species.

On

the otherhand,Ihaveyetto finditpresentinSpkyrapicus,although

Idonot positivelydenythat there

may

beexceptions to this rulelike- wise. It is invariablypresent in Colafies, a picineform which alsohas the longitudinal capital apteriumwellmarked.

The

remainderof the headin Pici,sofarasthe writer hasexamined them,isalways foundtobe denselyfeathered(Fig4).

Among Woodpeckers

the spinaltract offersus

many

and importantva- riations (see Fig.2,^, h,j, and Fig.5). Nitzsch discovered so

many

differencesin thisparticularinthe speciesheexaminedthatitwillbeim- possibletoenumerate themhere. Figure2showsvery well the distribu- tionof the spinal feathertract inD.v. Iiarri>ii\andFig.5,theinteresting departuretherefromin Sphyrapicus,inwhichlatter species thearrange-

ment

is

much

the

same

as

we

findittobein

many

typicalpasserinebirds.

InPicas-oiridisan interruption takes placebetween the narrowmedian neck stripof the spinaltractand the 'saddlearea'(//),and in Colaptes thisfeatureis likewisefairlywell marked. Colaptesagain has the pos- teriormoietyof the spinaltract,justas

we

findittoexist inDryobnfes, as

shown

inFigure2,atJ.

As

farasI

know

all

Woodpeckers

haveastrongly tuftedoilgland(Fig.i, /).

Faintly

marked

asaruleinallVici,the fetnoral iracfinColafies agvees in being but feebly traceable by the presence, on eitherside,ofafew

downy

feathers,andatthemost not

more

than

some

threeor fourcontour ones. Like Dryobates, however,Colaptes possessesoneitherleg,a well- defined 'crural tract,' occupyinga position similarto theone

we

findit in inthe majority of

Woodpeckers

(Fig.2,z"). Nitzsch, as I have else- wherestated,foundthe 'inner humeraltract' (Fig.2./)^absentonlyin the

Sumatran

species,which hedescribed as Pictisluridus;this charac- teristicandsharply definedthoughsmall feather areaispresentinallspe- ciesof Colaptes, asitisineveryAmerican

Woodpecker

that the writer haseversubmittedtoa pterylographicexamination.

On

the outer side ofthissmallerhumeraltract

we

alsofind,ineveryspeciesofWoodpecker, the larger 'humeral tract' proper, which,as ^is usual, passes obliquely across the region of either shoulder, as

shown

in Figure2ate,andin Figure5,whereit islikewisewellmarked. If

we

carefullyexamine,

we

shall findverysparselyappearingfeathers,forthemostpart

downy

ones, showing themselveshereandthereonthe apteria

among

the dorsal areas.

No

special descriptionisneededhereforthe 'alar tracts' in these birds, and

we

can next turn tothe ventral aspects of thespecimensunder con- sideration. Here

we

findthe feather areasverywell defined,

more

espe-

Figure2.— Dorsalaspect of thesame specimenshowninFigurei;b,capitalapte- rium;c,themedian(atthe point indicated) elevation of theskin caused bytheepi- branc'hialsofthehyoidean^apparatusbeneathit;g, spinal^tract;

/

^{innerhumeraltract}

;

h,lowerdilation ofspinaltract(the saddle);/,lower part of spinaltract(rumptract)

;

i,cruraltract;0,femoraltract(veryfaintlyseeninaWoodpecker);^,alartract.

Figure

3—

Anterior or ventral aspect of thesamespecimen, withitshead turned totheleft; a,capital tract; «,the ventral tract,and w,itsexternal branch. From nature,bythe author.

2l6

Corres^poiidence. ^[April

Figure4.

—

^{Ventralviewofa}plucked specimen of theRed-napedWoodpecker (Sphyrapkusv.nuchalis),showingitspterylosis. Fromnature,lifesize,bythe author.

ciallythe 'ventraltract'anditspeculiar externalbranch(Fig.3,m. and«).

Itwillbeseen that in Dryobatesthe

main

ventraltractisvery broad nearthe

summit

of the shoulder,andcontinuestobe sountil

we

arrive at the bifurcationwithitsexternalbranch;«,whichlattercurvesouttowards

Correspondence.

21

Figure^{5.— Dorsal}aspect of thesame specimenof SphyrapicusshowninFig.4, signedto illustrateitspterylosis. Drawnbythe author;lifesize.

21

8

Correspondence. [April

thesideasa sliarp-pointedand

handsome

hook(see also Fig. i),termi- natingina freeextremity. Figure₄showsthisarrangementtobe quite difterent inSfhyrapicus, wheretheform of the external branch is nar- rower,andtiiebifurcationhigherup towardstheneckof thebird. Ittoo, however,terininatesina free-pointedextremityatthe side.

The abdom-

inalpartof the

main

ventraltractis

much

strongerinSfhyraficus than

itisin Harris's Woodpecker,in whichlatterspeciesit usuallydwindles to a single row ofcontour-feathers beforearrivingat the vent. Both species have theapertui-e of the ventcompletely surrounded byasingle rowofsmall contour-feathers,while in Dryobatestheve are posteriorto thisregion amid-coccygealpteryla,withan obliquelateral one on each sideofit(Fig. 3). TheseIhavedesignated as the 'postventraltracts.'

Colaptes has,bothinarrangement andform, itsventralandpostventral tractsalmostidenticallythesameas

we

find

them

inthegenusDryobates.

Nitzsch, alluding to the rectrices and remiges in the Woodpeckers, says ''twelvetail-feathers,but thetwoouterones smalland bentin be- tween the two precedingones,"and "the wings bearfromnineteento twenty-oneremiges, butalwaysten on the pinion,ofwhich the first is rather short, thesecondislikewiseshorterthan the following ones, but the thirdissometimesequal to the fourth andfifth,and with

them

the longest,andsometimes exceeded bythe fourth,fifthandsixth,whichare thenof equal length."

Personsinterestedinthestudy ofthissubject

may

wellconsult besides Nitzsch's 'Pterylography' certain important papersinthe early issues of the'Proceedings' of the Zoological Society of

London.

Faithfully yours.

Fort Wingaie,

New

Mexico,

21StFeb.18S8.

R.

W. Shufeldt.

Polydactylism in Birds.

To THE Editors

of

the Auk

^:

—

Sirs:

— My

^{attentionhas been directedto a shortarticle in'The}

^Auk'

(Vol.IV,No.4,pp. 331-333, Oct. 18S7),on'Ornithological Curiosities.

—

A Hawk

with ninetoes,anda Bobolink with spurson its wings.' Ido not professtobeanornithologist,though

much

interested inthesubject, and somethingofanobserver of birdlife; Ipreparethisnote asa teratol- ogist. I

am much

pleased with the report of thecasesof the supernu- merary developmentby Mr.

Henry

K. Coale,and hopehisexamplewill be followedbyothersfrom

numerous

observersalloverthe land.

In

my

soinewhatextensive researchesforthepurposeof collecting and classifyingthebibliographyandreferences relatingto the'The Material of Teratology,'I have been surprised atthe infrequencyas well as the meagrenessof reports,andthe almost absence ofeven incidental inen- tion ofcasf^sofsupernumerary and duplex developmentinbirds. Suchas