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rikanske Arter ere naaede, men for ingen af de her nævnte 

 Fugles Vedkommende har der, skønt de alle ere i Ungedragt, 

 været nogen Vanskelighed med Artsbestemmelsen; der findes 

 mellem dem ingen amerikansk Pibeand. 



De Vanskeligheder, der vise sig, naar det gælder at skelne 

 mellem Krikandens evropæiske og amerikanske Forms unge 

 Fugle, Hunner og Hanner i Sommerdragt, findes næmlig ikke 

 for de tilsvarende Køns og Alderstrins Vedkommende hos ame- 

 rikanske og evropæiske Pibeænder, idet Axillarfjerenes Farve og 

 Tegning hos disse afgive et godt Skelnemærke. Dette har for 

 saa vidt længe været kendt, som Salvadori i »Catalogue of Birds«, 

 Vol. XX VH, S. 235 i Beskrivelsen af Mareca aniericana siger 

 »axillaries white« , men om de paagældende Fjer hos Mareca 

 penelops siges ganske vist intet; derimod findes følgende tydelige 

 Udtalelse om dette Forhold hos Seebohm i »History of British 

 Birds«, Vol. HI, S. 544: A further characteristic of the American 

 species, apparen^Iy showing its affinity with the teal, is that at 

 all ages and in both sexes the axillaries are pure white, with 

 only very slight indications of mottling near the tips«. Paa den 

 anden Side skriver J. G. Millais i sin »Nat. Hist. of the British 

 Surface-feeding Ducks« S. 57: »In first plumage the two birds 

 so closely resemble one another, that it is impossible to give 

 any specific characteristics«. For nylig har Spørgsmaalet været 

 berørt i »Auk«, Vol. XXVIH, April 1911, S. 192 af J. G. PhiUips: 

 »Ten years of observation on the migration of Anatidae at Wen- 

 ham Lake, Massachusetts«, hvorfra nedenstaaende hidsættes: 

 »While looking at the axillary feathers of various birds in the 

 Museum of Comparative Zoology, Mr. Outram Bangs recently 

 pointed out to me a new way of distinguishing at a glance, re- 

 gardless of sex or plumage, between M. aniericana and M. penelope 



The characters referred to above are as follows; 



M. aniericana, axillaries practically pure white, except for a very 

 fine dusky pattern at extreme tips or a slight duskj^ line along 

 the main shaft in some cases. M. penelope, axillaries markedly 

 dusky and finely patterned, especially on the inner webs. The 

 outer webs may be almost entirely white, giving an appearance 

 of white axillaries, until the feathers are spread apart. 



This distinction has thus far been found to hold good through 

 the entire series of Widgeon skins in the coUection of Mr. Wil- 

 liam Brewster and the Museum of Gomparative Zoology, com- 



5* 



