ANATIDJl. 



longed to the Rev. L. B. Larking, of Ryarsh Vicarage, 

 near Maidstone, for whom it had been preserved by Mr. 

 Leadbeater. It was one of four, shot on the Medway, 

 near Snodland Church, where a flock of thirty, and seve- 

 ral smaller flocks, were seen. 



The circumstance of these flocks being seen, without any 

 observable difference in the specimens obtained, all of 

 which were distinct from our Mute Swan ; the fact, also, 

 that the cygnets, as far as observed, were of a pure white 

 colour, like the parent birds, and did not assume, at any 

 age, the grey colour borne for the greater part of the first 

 two years by the young of the other species of Swans ; 

 and an anatomical distinction in the form of the cranium, 

 to be hereafter noticed, which was described by Mr. 

 Pelerin, in the Magazine of Natural History, induced 

 me to consider this Swan entitled to rank as a distinct 

 species, and, in reference to the unchangeable colour of 

 the plumage, I proposed for it the name of Cygnus immu- 

 tabilis. 



I was favoured with a letter from the late Earl of 

 Derby, who had purchased a pair of Polish Swans in 

 London, and sent them to Knowsley. The female in this 

 instance also, unfortunately died. The male paired with 

 a Mute Swan, and a brood was produced. A Polish 

 Swan also paired with a Mute Swan on the waters 

 in the Phoenix Park devoted to the use of the Dublin 

 Zoological Society. I was told by an excellent natu- 

 ralist who had seen these birds, that he was satisfied of 

 the distinction between them on seeing them side by side. 



I have heard of one Polish Swan shot in Cambridgeshire, 

 and now preserved in the Wisbeach Museum ; and another 

 was shot in the winter of 1840-41. This species, however, 

 does not appear to have been distinguished elsewhere from 

 the Mute Swan, and I am therefore unable to name any 



