Mr. A. Newton on the Harlequin Duck. 163 



trachea I believe no representation has hitherto been given, 

 though it has been described by Professor MacGillivray, first in 

 the work of Mr. Audubon (Orn. Biogr. v. 617), from which 

 the account is quoted by Mr. Yarrell (Brit. B. iii. 266), and 

 afterwards in the Professor's own book (Hist. Brit. B. v. 170). 

 As this description seems to be quite as detailed and accurate as 

 any I could furnish, and, when taken in connexion with the accom- 

 panying engraving, to afford a sufficiently good idea of its form 

 in this species, I need say no more on that head, beyond remark- 

 ing that, as will be seen from the figure, the bony tympanum of 

 the male is uninterrupted by any of those membranous openings 

 found in all the other Diving Ducks — except the Eiders* — with 

 which I am acquainted, and that in particular it bears no resem- 

 blance whatever to the same part in either the Golden-eye {A. 

 clangula, L.) or the Long-tailed Duck [A. glacialis, L.), the 

 typical representatives of the sections Clangula and Harelda, in 

 one or the other of which the Harlequin Duck is usually placed 

 by most of those ornithologists who subdivide the great and 

 natural group of Diving Ducks, and near which two species I 

 think all other writers agree in placing it. The specimens of 

 the trachea now figured were prepared by me from fine freshly- 

 killed examples of this beautiful species obtained last year by 

 Mr. John Wolley and myself from a merchant at Reykjavik, the 

 capital of Iceland, and, excepting one in the Museum at Haslar 

 Hospital, no others, to my knowledge, exist in this country. In 

 these examples, when fresh, the small lobe on each side of the 

 base of the upper mandible, which seems to have escaped the 

 notice of many, if not of most, ornithologists, though it has 

 been duly remarked by some, was very apparent ; and I am not 

 aware that this external character exists in any other of the 

 species with which the Harlequin Duck has been usually asso- 

 ciated. Indeed, in many dried skins which I have examined, this 

 peculiarity is very easily overlooked, as, unless care be taken to 

 prevent its doing so, it usually shrinks into insignificance as the 

 skin dries, whereas while the bird is fresh it is of a prominent 

 size, although smaller in the female than in the male. 



* In the Scoters, it will be recollected, there is nothing that can properly 

 be called a tympanum. 



