506 MR. p. L. SCLATER ON THE [June ] 5, 



2. Cygnus immutabilis, Yarr. Polish Swan. 

 Cyynus immutabilis, Yarr. Brit. B. iii. p. 131. 

 Hab. Northern Europe. 



In one of our registers it is said that an examjjle of this species was 

 in the Gardens in 1830, but it is not included in the general list of 

 1831. 



Mr. Yarrell speaks of a pair of this species (or subspecies of C. 

 oZor) as living at Knowsley, where the male paired with a female Mute 

 Swan and produced hybrids, and two were sold at the Knowsley 

 sale in 1851. 



In 1871 we obtained a living pair of this Swan, which were sub- 

 sequently deposited with Mr. J. H. Gurney, F.Z.S., for the purpose 

 of breeding. See Mr. Gurney's note on this subject, P. Z. S. 1876, 

 p. 46G. 



Mr. Gurney has kindly furnished rae with the subjoined addi- 

 tional particulars : — 



" I fear I cannot give you much information respecting the 

 breeding of the Polish Swans or the colour of their cygnets beyond 

 what is contained in my note in the P. Z. S. for 1877, p. 579. 



" They have reared a brood during each subsequent year; but as I 

 have been from home more or less every spring I have kept no 

 detailed notes about them since 1877- The number they have 

 hatched annually has varied from 4 to 6, so that they are not a very 

 prolific pair as compared with some common Swans. This year 

 they hatched four, of which one was killed by rats. All the cygnets 

 have resembled in colour those described in my former note." 



3. Cygnus musicxjs, Bechst. Hooper Swan. 

 Cygnus ferus, Gould, B. G. Brit. v. t. 9. 



Hab. Palsearctic Region. 



The Hooper bred in the Society's Gardens in 1839 (June 16), 

 1841 (May 27), and in 1842 (May 20), but has not done so of late 

 years. It cannot be considered by any means a free breeder in con- 

 finement. 



4. Cygnus americanxjs, Sharpless. American Swan. 

 Cyynus americanus, Baird, B. N. A. p. 758. 



Hah. North America. 



I have never heard of this Swan having been brought alive to 

 Europe, nor am I aware that it has been exhibited in any of the 

 American gardens. 



5. Cygnus buccinator. Rich. Trumpeter Swau. 

 Cygnus buccinator, Baird, B. N. A, p. 578. 



Hab. Western North America. 



Our first examples of this Swan were received in 1866 (see 

 P. Z. S. 1866, p. 203). The first pair bred in 1870 (June 6th) (see 

 P. Z. S. 1870, p. 664). Young ones were also bred every subsequent 

 year up to 1876, but our stock is now unfortunately reduced to a 

 single bird. 



