68 CLARK,Pterylosis o/Swt/ls and Hummingbirds. [Jan.[Auk bird. There is no evidencethat griseusinterbreeds with marianet, and I think it shouldbe givefull specificrank. The breeding rangeof griseusextends along the South Carolinacoast as far no•Xhas the •nouthof the SanteeRiver. A glanceat the •nap of South Carolina, will showthat thcre are no salt m•rshcsof any ' extentfrom Georgetown to Southport, N. C., in whichthis wren could breed. THE FEATHER TRACTS OF SWIFTS AND HUMMINGBIRDS. BY HUBERT LYMAN CLARK. Plates II and III. SOMEyears ago I undertookto obtain•naterial for a studyof the arrange•nentof the feathertracts in the Swiftsand Hmmning- birds. Through the kindnessof the authoritiesof the United States National Museran, the alcoholic •naterial in that collection wasplaced at •ny disposal,and wascarefully exmnined. Later on, stonebeautiful hunnningbird•naterial frmn Arizona carne into•ny possession through the effortsof Mr. R. D. Lusk,and in 1897,Mr. C. B. Taylor of Kingston,Jmnaica, presented •ne with somevery valuable speci•nens of both swifts and hmmningbirds. In April,1901, a briefstate•nent appear.ed in 'The Auk' concern- ingthe conclusionsto which the study of this•naterial had led •ne, and a •noreextended reference to the•n appearedin 'Science'for January17, 1902. The preparationof theentire report, however, wascontinually postponed in the hopeof obtaining•nore speci- •nens,and in July,1905, through the kindness of Dr. Wit•nerStone, stonealcoholic hmmningbirds frown Brazil wereloaned •ne by the Academyof Natural Sciencesof Philadelphia. As thereis little Vol.1906 XXIII] j CJ,AI•Xr,Pterylosis o[Swi]ts and Hummingbirds. 69 probabilityat presentof securingin this countryfurther material of importance,I havedecided to delayno longerthe publication of this account of the work that has been done and the conclusions reached. It isan interesting fact that t•he pterylography of no group Of birds has received so much attention as has that of the swifts and hummingbirds.•The classicwork of Nitzseh('40) dealsquite fully with the matter,so far as his materialand methodsallowed. Shufeldt('88) has given a veryfull account6f thepteryloses of both swiftsand hummingbirds,making use howbver of Nitzsch'sfig- ures,which are, unfortunately, very inaccurate. Lucas ('92) has describedthept•rylosis of the hummingbirds in Ridgway's paper on that group,giving figures of the dorsaland ventralaspects of Florisuyamellivora. Thompson(:01) has describedin full, and figuredwell, the pterylosisof Patayona9iyas, comparedit with bothCaprimul.qus and Colloealia, and given a figureof thedorsal aspectof the latter. His conclfisionswere criti•ised by me'in 'Science'(January 17, 1902) and Shufeldtpublished a counter criticismin 'Thd Condor'(March-April, 1902), to whicha brief replywas made in the nextissue of the samejournal (May-June, 1902). Discussioncenters around the questionwhether the swifts andhummingbirds have essentially distinct and uniquepteryloses or not,and to thisquestibn we shall return when we have completed an examinationof the evidencein the case. The pterylography of the sw'iftswill be consideredfirst, a brief generaldescription of the cypselinepterylosis being followed by a ghortaccount of each'genusexmnined. The accountof thehummingbirds follows in the sameWay, after whichtim tw6 groupsare' compared, and final conclusions stated. In this connectionI Wishto thank Mr. Lusk, Mr. Taylor, 1Mr. Stone,and especially Mr. F. A. Lucas,for thehelp they have given me in securingthe neededmaterial, without which nothing could havebeen done, andto Mr. Stoneand Dr. J. A. Allerl,I amindebfed for assistance in nomenclature. 70 C•,At•K,Pterylosis o[Sw•[ts and Hummingbirds. L[-AukJan. CYPSEIA. The generalpterylosis of the swifts is verydistinctive and rE- xnarkablyuniform, so that the figuresof Choeturapelagica (Plate II) will answerwith slightchanges for any of the otherspecies. The tractsare all clearlydefined and well feathered,while the apteftaare uniformly naked. The foliehead isquite thickly feath- ered,but with largecreseent-shaped aptefta over the eyes,while the crownand occiputare rathersparsely leathered, in longitu- dinal rows. The throat is fully featheredbut there are a:pteria alongthe raxniof the lowerjaw. The uppercervical tract is very broad,and unitesalong the sidesof the neckwith the lowercervi- cal tract, so that there are no lateral cervicalaptefta. Between the shoulders,it bifurcatesto form the dorsaltract. On the ante- rior part of the neck,close to the head, is a large and very evident apteriron,ode of the mostcharacteristic features of the pterylosis. It is a verycurious fact that Shufeldt('88 and :02) positivelydenies the existenceof thisapterium in the swifts,while I,ucas ('92) states that "soxneof the swifts"possess it, and Thompson(:01) xnakes no referenceto it in his descriptionof Collocalia,though his figure showsan entireabsence of featherson the anteriordorsal part of the neck. A carefulreSxamination of xny material,figures and notes,leaves no doubt whateverof the existenceof this apterium in everyspecies of swift examined. I can only accountfor Shu- fehlt'sstatements by supposingthat they are basedon his exaxni- nationof Choeturapelagica and A•ronautesmelanoleucus: in Choe- turathis apteriron is notvery large, while in A•ronautesit is smaller than in any other swift. It is not inexplicabletherefore that it wasoverlooked in thesecases, but it is hard to seehow it couldhave beenoverlooked in Cypseloides,which he alsoexamined.--The dorsal tract is divided from the shoulders to the middle of the sacrmn,by anotherlong but narrowapterium, il•to two narrow bandsof nearlyuniform width, but it endsin a singlenarrow band at the baseof the oil gland. The anteriorportion of the spaee betweenthe dorsal and humeral tracts is sometimesseparated from the rest so as to form a s•nallbut quite distinctapterium on eachside of the uppercervical tract. This is wellshown in Cha•- Vol.1000 XXIIF[ / C•mK,Pterylosis o[Swi[ts and Hummingbirds. 71 tufa. The fernoraltracts thoughdiffuse, are very evident,and are usuallylong, so that they extendbackward almost or quite to the tail-coverts,while anteriorly they reachdownward and for- ward, often to the sternalsand along the sidesto the posterior end of the humerals. The latter tracts are narrow or of moderate width, passingover the humeruseither at its head or near the middle,and are clearly connected with the featheringon the pata- gia of thewings and evenwith the uppercervical tract. The large oil glandis almostsurrounded by a smalltract, chiefly made up of the upper tail-coverts. The lowercervical tract is forkedquite far forwardon the neck, and each half passesinto a broad sternaltract which continues without interruption,though becoming narrower, to the belly, whereit endsrather abruptly. In manyswifts just at the point wherethese pteryl•e leave the neckand passon to the breast,an anteriorlydivergent fork of the ventral apteriumnearly severs them; thisis mostevident in Chazturaand Hemiprocne. In some of the large swifts (Hemiprocne,Cypseloides) scattered feathers in the regionof the furculumtend to unite the anterior endsof the 2 sternaltracts. There is nothingelse peculiar or specially noteworthyin the ventralpterylosis, but the sternalsare connected anteriorlyover the shoulderswith the humeraltracts and posteri- orly, occasionally,with the fernorals. The characteristicand importantfeatures of this pterylosis maybe summarizedas follows: the presenceof supraocularapteria, an uppercervical apterium, and a long and conspicuousspinal apterium,the absenceof lateral cervicalapteria, the large and diffusefernoral tracts, and the continuityand markeddevelop- ment of the lower cervical,sternal and ventral tracts. In addition to thesefeatures, the followingpoints are noteworthy. Aftershafts are presenton the contourfrethers and are oftenvery large. True downfeathers are wantingand filoplumesare not notablyabun- dant, thoughusually evident on the neckand the posteriorpart of the back. The oil glandnever bears a terminaltuft of feathers. There are always10 rectricesand 10 primaries. The alula con- sists of 2 or 3 feathers and in some cases there is also a distinct claw. The secondariesare usually8 or 9 in number,and the wing quineubital,but in Cypseloides,Hemiprocne and Mactop- 72 Pteryl•siso/Swi/ts and Hummingbird,•. ,, LFAukJan. teryxthere are 10 or 11sedondaries &nd fhe wing 'is aquihcubita!. Exceptin Macro?teryxand C•llocalia, the skin'on the hand is verydark, and thi• darkeningextends in somecases'not only along the forearmbut nearlyto the shoulder. The aboveaccount of the cypselinepterylosi• is basedupon the examinationof 15 •wifts,representing 10 spediesand 8 g6nera. Nitzsch('40) studiedH•miprocne collaris Tdmm., H. acuta(C•/ps. acutusPr. Max v. Nen Wied.) and Cypselusapus; Shufeldt('88), Chcetura]•elagica, A•ronautes melano'leucus, and Cypseloidesniger; and Thompson(:01), Collocaliaepodiopyga; but sofar aSI know, thepterylosis has not been examined in anyOthers of'the Cypseli. The generawill now be consideredin detail. ' MaCropteryx. It is especiallynoteworthy that the pterylosisof' this interesting genusdoes 'not differ in any essentialpoint from that of Chetura. The nuchalapterinto is .presentbut is quite small,as the upper cervical tract is comparativelylong and narrow. The fernoral tractsare notablystrong posteriorly. The legsare featheredabout to the tarsal joint. The skin on the hand is not dark. The 10 rectrices,10 primaries,1l secondaries,and3 aiulafeathers are not peculiar,'but the