PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 195 

 Cygmis umcini Hume. 

 Kuobless Swan. 



DiAGN. — Culmen tcithout knob ; legs in the adults slate-colored ; young 

 gray or brownish gray. 



Syn. — ? 1804. — Anas dirccca Hermann, Observ. Zool. I, p. 139. 



1862. — Cynus immutabiUs v. Pelzeln, Sclir. Zool. Bot. Ver. Wien, xii, p. 785 



(nee Yarr. 1838). 

 1871. — Cijgnns unwlni A. 0. Hume, Ibis 1871, p. 413. 

 1871.— Ciigmis olor Salvin, Ibis 1871, p. 413 (uec Pall., nee Gm.). 

 1872. — Cygnus iirwini Gibbel, Tlies. Oru. I, p. 857. 



Note 1 to the synonymy. — Dkesser cites Hermann's Anas dircwa as 

 belonging to immutabiUs Yarr. with a query. Because the descri])tioa 

 of the said author contains the phrase "corpore ciwereo" I regard tliis 

 reference unadvisable. The resembLance of the title Cygnus polonicus^ 

 cited by Hermann, and the English name, "Polish Swau," is of no 

 consequence for the reason that such a title is not to be found in 

 Gesner, in spite of the quotation.* It belongs rather to the species 

 here in question, but the phrase ^'rostro rubro''^ makes me hesitate, 

 because I am not satisfied whether the young of this species has a red 

 bill or not. From the description of Hume it seems that it should not 

 be the case. Hermann does not speak about the knob, it is true, but 

 if it had been completely absent he should not have failed to mention 

 it. I have therefore introduced it into the above synonymy with some 

 doubt. 



Note 2. — The museum at Vienna received in the year 1857 three adult 

 swans which Mr. Zelebor had captured in the month of March the 

 foregoing year, and which had been deposited in the imperial menagerie 

 at Schonbrunn, near Vienna, where they died in the beginning of the 

 said year. Misled by the statement that white and gray cygnets had 

 been found in the same brood, Mr. A. v. Pelzeln, in a short article 

 (1. c), identified the specimens with the C. immutahiUs Yarr. 



Mr. A. V. Pelzeln has had the great courtesy to send one of the 

 specimens a great distance for my inspection, and I am thus enabled to 

 make up my own ojiinion. 



As fiir as I can judge the specimens in question are distinct from both 

 the gibbus and the immutabiUs. From both these species they are sep- 

 arated by the complete absence of even the slightest trace of a tubercle 

 or knob, by their inferior size, and by the different form of the bill. 

 From the former, with which they agree in having the plumage of the 

 young brownish, they are further distinguishable by the legs and webs, 

 which are "slate-colored, changing into olive," and from the latter by 

 having a brownish and not white plumage of the young. 



'' Hermann quotes: Gesner, Edit. Francof. 1604, p. 273 B: but on p. 373 B (on p. 273 

 lie treats of Ciconia) lie only says: "1h Polonia cygni sunt divcrsi generis; sunt enim alij 

 feri, 2)ari magnitudine, alij domcstici, quoi'um vox suavis est, ij- tuba refert." 



