ANATOMICAL NOTES ON SOME GENERA OF PASSERINE

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262

Clark, AnatomicalNotes.

[a^u.

ANATOMICAL NOTES ON SOME GENERA OF PASSERINE BIRDS.

BY HUBERT LYMAN

CLARK.

There

are

many

generaofPasserinebirds, therelationships of whicharestill

more

orlessuncertain,largelyowingtoour lackof knowledge of their anatomy.

Thanks

to the kindness of Mr.

Outran! Bangs, and his interest in having our knowledge along these lines extended, some alcoholic material has already been placedin

my

hands and

more

ispromised,whichwillenable

me

to study the

anatomy

of someof thesegenera ofdoubtfulaffinity.

Through

thekindnessofDr. C.

W. Richmond

andtheauthorities ofthe United StatesNational

Museum,

to

whom

Ihere express

my

hearty thanks, representatives of the three following genera have beensentme, andIventure to present here theresults of

my

studies. Such studies can onlybe carried on withprofit, where large collections of skins and alcoholic birds are accessible for comparison,andI

am

thereforeindebtedtoMr.

Henshaw

and

Mr.

BangsforthefreedomwithwhichIhave beenpermittedtouse the collections inthe

Museum

ofComparativeZoology.

Saltator.

An

adultmale specimenof Saltator africcpsLesson,from Mexico, lacking wingand tailfeathers, but otherwise in good condition, preservedinalcohol,hasbeencarefullystudiedincomparison with PipiloandPiranga.

The

charactersofthebillandfeet ofSaltator aretoowell

known

toneedany

comment

from me,while thetongue showsno distinctivecharacter. Itisso similar tothat of Pipilo that the onlydifferenceisitsslightlygreaterfleshiness.

Picrylosis.

The

general pterylosis of Saltator is like that of most oscinine birds and reveals no really distinctive feature.

The

upper cervical tractislong andnarrow, only three feathers wide for most of its length, but the dorsal tract has the usual rhomboidalform. Otherspecimens

show

thatthewingispointed

by

the sixth primary, which isnearly equalled

by

the ^fifth and

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°i9i3^"J Clark, AnatomicalA'otes.

263

seventh; the fourthislonger than the eighthwhichisabout equalto thethird; thesecondislongerthan the ninthwhich

may

l)eeither longer or shorterthanthefirst. Thisarrangementofthe primaries

isquitedifferentfromthatshown byPiranga butisalmost exactly likethatfoundinPipilocri/throphthalmus.

The

tailis \-ery

much

graduatedandis

made

upof12soft, broadrectrices.

AUmcnfanj Canal.

No

notable characters are shown by the intestine orstomach,whicharenot distinguishablefrom thoseof Pipilo.

The

intestinemeasures about225

mm.

inlength,or rather lessthanthetotallengthofthebird,but oneandahalftimes the lengthofthebird,iftherectricesarenotincluded.

The

stomach contained seedsand thepit ofasmall, cherry-likefruit,as wellas

much

undetermined vegetable matter; no insectswere noted.

Palatine Region.

The

palatine processes are longandconspicu- ous as in the finches and tanagers generally. There is a well- developed "secondarypalatineprocess"on eachside

much

as in Habia, although not so long or conspicuous as in that genus.

They

are rather betterdevelopedthaninPiranga.

The

maxillo- palatines arenotpeculiar.

Sternum. There is no trace of an 'osseous bridge' from the anteriormarginofthesternum tothemanubrium,suchasoccurs in Piranga and Rhodinocichla.

Back

of the anterior margin whichisverticallyvery

much

thickened thereisabonyroofo\er the small space contained between the anterior margin and the sloping sides of the sternal floor. This bony roof is present in

many

finchesandtanagersbutshowsgreatdiversity initsextent and appearance. In Saltator, it isperforated bya conspicuous, circular, median foramen, posterior to which is a second

much

smaller opening. Therearenoopeningsin thisbonyroof in Pipilo butinHabia, there aretwoas inSaltator although theyarevery

much

smallerthaninthatspecies. In Piranga, thereare,in the male, two verylargeforaminaside

by

sideanda smaller opening

may

be seeninthe posteriorface of theanterior margin; ⁱⁿ the female,thelargeforaminaseemtobe wanting. Whetherthisbony roof and these foramina have anyspecial significance I

am

not prepared to say, but their appearance in Piranga (male\ Habia andSaltatorisstriking.

Conclasiona.

The

resemblanceofSaltatorto Pipilo in itsana-

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264

Clark, AnatomicalNotes. [A^n tomical featuresisstriking,while intwodetails (secondary pala- tineprocessand forameninosseous roofabovesternum)inwhich

itdiffersfromthatgenusitresembles Habia. Itlacksthe^'osseous bridge'ofthe sternal

manubrium

so

marked

in Pirangaand Rhodinocichla. It seems to

me

thereforethat

Ridgway

is right in placing Saltatorinthe Fringillidre.

Chlorophonia.

An

adultmaleofChlorophonia callophrys (Cabanis)from Costa Ricahasbeenat

my

disposal. Ithasbeen comparedchiefly Avith Piranga and Euphonia. Unfortunately alcoholic specimens of other Tanagridpehavenotbeenavailable,exceptingRhodinocichla.

The

charactersofthebilland tongue need no

comments

from

me

butthetarsishowacertaincharacterwhichdoesnotseemtohave been noted hitherto.

Tarsus. Examination of the alcoholic specimen revealed the interesting fact that the tarsi are distinctly booted.

The

three scales whichusually cover the frontofthe tarsusintanagers are fused togethersothat thereishardly atrace ofthelinesof division.

On

notingthisfact, Iexaminedalarge

number

ofskins ofChloro- phonia (5 species),Pyrrhuphonia, and Euphonia(10 species) and severalgeneraofmoretypicaltanagers,with theresult,whichwas surprisingtome,thatabootedtarsus,asperfect asthatofa thrush,

isby no

means

rare

among

thesetanagrinebirds. Ifinditoccurs in Pyrrhuphonia constantly inboth sexes and

may

wellbe con- sideredoneofthe genericcharacters. Itisalso fairlyconstantin Chlorophonia callophrys, longipcnnis, riridis, frontalis psiitacina, andoccipitalisbutislessfrequentintypical frontalisandinpretri.

In all thesecases adult males generallyhave the tarsus booted, butinthe females^asarule,andintheyoungthedivisionsbetween the scutes arestilltobeseen. InEuphoniaaffinis,bothsexes are, asarule,booted butinmostspecies ofthe genus, the scutesonthe frontofthe tarsus are quitedistinct. Bootedtarsiarealsofound, atleast inadultmalesofCalospiza,Poecilothraupis,Hemithraupis, Chlorospingus and Mitrospingus. ^>ry probably they \x\\\ be foundinother generaand theiroccurrence throughouttheTana- gridiedeserves detailed in^•estigation.

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^"ioi^?"'^] Clark,AnaiomicalNotes.

265

Picrylosis.

The

general pterylosis of Chloroplioiiia deserves

comment

because of the noticeable width of the tracts and the densityoftheir feathering. Thisisparticularly true oftheupper cervical tract.

The

dorsal tract ('saddle') is not as broadly rhombic as in most oscines but the outer angles are rounded.

The

posterior end of the'saddle'isalmost completely separated fromtheremainderofthedorsal tract,whichisatfirstnarrow and withfewfeathersbutbecomes broadandwell-featheredattheoil- gland.

The

sternal tracts areabruptly contractedwherethey pass intotheventrals. Thereare nine primariesandnine secondaries in the wing; the sixth, seventhand eighth primaries are nearly equal, theseventh atriflethe longestperhaps; theninth^isnext, withthefifth,fourth, third,secondandfirstinregular succession.

Therearetwelverectrices of approximately equal length,though the outerones are ofcourse (sincethe tail is nearly square-cut) really the longest.

Alimentary Canal.

The

stomach is small but quite distinct.

One

can distinguish a proventriculus about six

mm.

longand a gizzard ofaboutthe

same

length.

The

latterhasthin wallsbut the inner surfaceishard andcorrugated,so thereisnoreasonfor refusingtocallitagizzard. Forbesstates (P. Z.S.London,ISSO, p.145)thatinChlorophoniaviridisthereis"thesamenon-de\elop-

ment

ofa gizzard" asinEuphonia. Itiscurious that there should be a noticeabledifferenceonthispointwithin thelimitsofasingle genus, butcertainly in Chlorophonia callophrysthe gizzard is far better developedthaninEuphonia.

The

intestineinChlorophonia

isextraordinarilylong; inthespecimenbefore

me

itmeasures340

mm.

or

more

than2| times thetotallengthofthebird. Naturally inits arrangementwithin thebodycavity

we

findtwo morefolds than isusual

among

tanagers.

The

stomach contains seedsand indeterminable vegetablematter andremainsofat leastoneinsect.

Palatine Region.

The

bony ^palateis remarkable for the very short palatineprocesses.

They

areasshortandbluntorrounded asin

many

Mniotiltidse,sothat the palateisnotatalltanagrine in appearance. There is no secondary palatine process and the maxillo-palatinebonesshow nopeculiarities.

The

vomerisnotice- ablybroadandthick,with theanteriormarginnot deeply notched.

Sternum. Thereisnotrace ofthe osseous bridge norof forann'iia

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266

Clark, AnatomicalNotes. [apJu inthe bony roof ofthespace backof theanteriormargin ofthe sternum. Inall particulars,the sternumappears to betypically fringilline.

Conclusions.

The

details of anatomy.here given throw very littlelightontheaffinitiesofChlorophoniabutthereisnospecial relationship to the tanagersshown.

The

palatine structure and the peculiarities ofthealimentary canalbothtend to separateit

fromthat group.

EUPHONIA.

An

adult maleof Euphonia miniitafrom Costa Ricahas been availableforstudy and comparisons have been

made

chiefly with Chlorophonia.

The

bill and feet need no discussion here; the characterof the tarsal coveringin Euphoniahas been described above underChlorophonia.

Tongue.

The

tongue of Euphonia is strikingly different from thatofChlorophoniaoranyofthe tanagrinebirdsIhave examined

and

resembles thatofsomeoftheCoerebidse. Itisalmosttubular, thesides being rolled inward but not quite meeting.

The

tipis brushy.

Pterylosis.

The

general plan of the pterylosisis not peculiar.

The

dorsal saddle is

more

nearly rhombic than in Chlorophonia and the other tracts are not so broad nor so densely feathered asinthat genus.

The

arrangementofthe nine primariesisessen- tiallythe same,buttheeighthisslightlythe longestandtheninth

is a triflelonger thanthe sixth. There aretwelve nearly equal rectrices.

Alimentary Canal.

The

genus Euphonia has long been noted for the apparent absence of a stomach.

The

specimen at hand doesnotseemto differ essentiallyfromtheonefiguredby Forbes

(1. c).

The

intestineisverylong, about 180

mm.,

or twice the totallengthofthebird,andis

much

convoluted,as inChlorophonia.

Palatine Region.

The

palateof Euphoniahasbeen figuredby Parker (Trans. Zool. Soc. London, vol. 10, ^pi. 46,fig.3) and the specimen before

me

agrees well with that figure except for the apparent absence of maxillo-palatines. Parker indicates these bones ratherindefinitelyand I have foundnothing thatseems to

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°i9i3 J General Notes.

267 me

tocorrespond with them.

The

palatine processes areremark- ably long and pointed, a very characteristicfeatureof theskull andstrikingly differentfromthe conditionfoundinChlorophonia.

The vomer

is deeply divided anteriorly as Parker has shown andthusisquitedifferentfromthatofChlorophonia.

Sfenuou.

The

sternum shows noneofthe tanagrinepeculiarities of Pirangabutisalmost exactly similar to thatofChlorophonia.

Conclusions.

The

differences between Euphonia and Chloro- phoniainthetongueandpalate aresomarkedas to

make

onehesi- tatebeforeassertingthat thetwogenera are nearlyallied. Differ- encesinthealimentary canaland inthefeetalso,

may

notbeig- nored. In allofthese featuresEuphoniaapproachessomeofthe Coerebidffi-andthepossibility ofitsrelationship tosome

members

ofthatfamilyshould not beignored. Itishoweverpossiblethat Euphonia minutaisnot representativeofthegenusandthatsome otherspecies

may

show moretanagrineaffinities.

GENERAL NOTES.

HolboeH'sGrebeinConcord, Mass.

— On

December 15,1912, Bate- man'sPondfrozeoverwath blackice,butathaw andrainresultedonthe 17thincovering theicewithnearlyaninchofwater. Duringthemoon- lightnight that followed aHolboell'sGrebe (Cobjmbusholbaelli) attempted to light inthepond andIbelievesettlingontheiceandwasunable again totake wing.

On

the following morning,ithavingturned cold during the night,the birdwas foundwithitsbreast feathers frozenintheice. The wristsofitswings were badlylaceratedbybeating against theiceto free itself, butinother respects the birdwasuninjured. Aftermuchpiteous squawking,itsfeatherswerecutfromtheiceandthe bird Uberated. Its wings,however,wereinjured sobadlj'thatitwaskilledandisnow^pre- servedin thisMuseum.

—

R.

Heber

Howe,Jr., ThorcauMuseum,Concord, Mass.

AdditionafNoteson'the Harlequin

Duck

in

Wyoming,—

In 'Tlie Auk'forVtuiuary, 1913, pp. 106-107,Irecordedtwo malespecimensofthe Harlequin Duck whichI sawat Teton Lodge (Moran ^Post^Office), ⁱⁿ Jackson Hole last September, and which were supposed to have been