Mr. K. 13. Sliar])e on the American Eider DucJc. 51 



■\* Pleurotoma Bertrundi^ l*ayr. Ranges from Soutli France 

 to the Moroa. 



hrciijatiij Phil. 'J'his i.-^ the typical tbrni, -vvhich is 



not found living north of the Channel Islands. It is a 

 rare fossil. 

 — '*'(/«) Mont, (moderately common). 



-, var. semicostata, Jeffr. Ilah. Channel Islands. 



*. 



(urricuhij Mont. 



Ci/pnra europaOy ^lont. 

 Utriculufi triincatulu.s, Brilg. 



obtusus, Mont. 



* Lajonkairiana, Bast. 



* Bulla hi/datis, L. (fragments only). 



* Conovulus hidentatus^ Mont. 



Rhizopoda. 



Cornuspira foliaceuSj Phil. 

 Biloculitia, sp. 



ECHINODERMATA. 



Echinocyamus pusiUus. 

 Spatangus j)urpureus. 



VI. — On the American Eider Duck. By R. B. Sharpe, 

 F.L.S. &c., Librarian to the Zoological Societ}' of London. 



Some time ago I received a hint from Mr.D.G. Elliot, so well 

 known for his great work on the Birds of North America, 

 that the Eider Duck of Europe was not identical with the 

 Eider of America, although both species had, from the time 

 of Linnffius, been united under the name of Somaferia 7nollis- 

 sima. Mr. J. H. Gurney also wrote to me independently on 

 the same subject; and having had occasion to examine the 

 matter when writing the history of the Eider Duck for the 

 * Birds of Europe,' I find that the surmise of both Mr. Elliot 

 and Mr. Gurney is correct, and that the American Somateria 

 is not the same as the European species. To begin with, 

 the American Eider Duck is a very much finer bird than its 

 European congener, and both male and female have the 

 sickle-shaped inner secondaries more fully developed. The 

 chief difference, however, lies in the bill, the form of which in 

 each species is illustrated by the accompanying woodcuts. 



From these it will be seen that in Somateria Dresseri, as I 

 propose to name the American bird, the bare ridges running 

 up from the nostril to the eye are very much broader, and 

 also difier in being distinctly rugose. Again, the sea-green 



4* 



