436 Mr. N. A. Vigors on the Anus glociUuis of Pallas. 



has subsequently been included among the Birds of Great 

 Britain by writers on British Ornitliology ; but no further ac- 

 count has reached us of tlie specimen alluded to by that dis- 

 tinguished naturalist, nor has it been ascertained whether it 

 was preserved after it was communicated to him. The speci- 

 mens of both male and female, from which I have taken the 

 above description, v, ere sent up from a decoy near Maldon in 

 Essex, to Leadenhall-market, in the winter of 1812-13. Here 

 they were observed by a respectable naturalist *, who imme- 

 diately })urchased them and set them up. From his collection 

 they have subsequently passed into mine. There can be little 

 doubt of the two birds being sexes of the same species. They 

 agree in all the essential particulars that serve to identify the 

 species of this family; their biU, legs, imd feet exactly accord- 

 ing in structure, and the colouring and markings of the specu- 

 lum on the wings, a distinguishing character among the Ana- 

 tide^, being precisely the same. We have moreover, in favour 

 of this conclusion, the negative evidence that the other sex of 

 neither of these birds has until now been ascertained ; and we 

 have the ]:)ositive evidence that both these specimens were 

 taken in the same decoy and at the same time. 



The Qiierquedula glocitans, or Bimaculatcd Duck, is readily 

 distinguished from every other species of the family by the two 

 ferruginous spots on the cheeks, in conjunction with the form 

 of its tail, in which the two middle feathers somewhat exceetl 

 the others in length. Tlie other European species of the 

 Auatidce, whose tails are elongated, are tlie Anas gladalis, 

 A. boschas, and the A. acuta of Linna'usf. From the foimer 

 of these it is at once distinguished by strong generic charac- 

 ters ; the A. glacialis %, from its lobated hallux, its legs being 

 thrown behind the equilibrium of the body, and its conse- 

 quently superior habits of swimming and diving, being placed 

 at that extreme end of the family which leads off to the true 

 oceanic birtis, or typical Natatorcs; while the Q. gloc/iaus be- 

 scarcely 111) self draw tliat coniliisiori ; the roiiml spots on the side of the 

 head in the former species being superseded by long narrow stripes in the 

 figure of the btter; while the tail is completely roiwided, the two middle 

 feathers not being longer than the rest. Mr. Pennant's own figure of this 

 bird is an excellent representation. J must here notice what apjjcars to be 

 a slight difference between oar two birds. In the British Zoology the 

 species is described as having twelve tail-feathers : in my specimens^ both 

 of male and female, there are sixteen. 



* Mr. George Weighton, of Fountain Place, City-road. 



t These are the Ilarelda glacialis, Anns liosctins, and D ■fila acuta of 

 Shaw's Zoology. 



:f 'i"hc Anas nigra, Linn, also has the tail somewhat acute; but, equally 

 with .1 I'ltcialis, stands at a remote extreme of the family I'rom (^.i^tmi/ans. 



longs 



