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Show 590 PROF, GIGLIOLI A N D C O U N T T. SALVADORI O N [Dec. 6, Coscoroba davidi, Stejn. Pr. U. S. National Mus. v. p. 180, (1882). Two specimens from Possiette Bay, shot between the 12th and 25th of October, 1879. a. 31 Immature specimen of a greyish-white colour ; it has the following dimensions :-Wing 0*520 m.; tail 0*160 m, ; bill (culmen) 0-070 m.; bill (from gape) 0080 m. ; tarsus 0*100 m. b. 2 ? Whiter than the male, and therefore older, but shows also the greyish tinge of youth. Dimensions :-Wing 0*500 m.; tail 0*155 m.; bill (culmen) 0068 m. ; bill (from gape) 0*077 m.; tarsus 0*090 m. These specimens are evidently young birds, as is shown by the greyish tinge in both ; in each of them the lores are covered with very small feathers, those of the forehead descend on the culmen of the down to the two curved angles which run along the sides of the culmen ; again, in both the bill is mostly of a yellowish colour, and only the tip for less than one third of the total length is black; also the nares appear to open in a small black area. On comparing our two specimens with an adult example of C. bewicki, one of us noted a very great similarity. The size and dimensions of the wing and feet are nearly the same ; the greatest difference appears in the bill, which is smaller (narrower and shorter), but thi difference looksgreater than it really is on account of the feathers which cover the lores and the base of the bill; should these feathers eventually disappear, supposing (as one of us does) that they may be a juvenile character, then the difference in the size of the bill between our two Corean specimens and the adult C. bewicki with which they have been compared might be accounted for by age. The difference in the distance between the tip of the bill and the external corner of the eye is hardly half a centimetre, being 0-112 m. in the adult C. bewicki, and 0*107 m. in the female from Possiette Bay. The dried feet in both our specimens seem to have a greenish colour with some traces of reddish brown. It appears no easy matter to recognize in the two birds before us specimens of David's Swan, a species as yet so very incompletely described, from the unique specimen, a mutilated one, said to be still in the Museum formed years ago in the Lazzarist Mission- House at Peking by the worthy Pere David, unless moths and dust have destroyed it. It is strange how deficient both the descriptions of Swinhoe and David of that type specimen are ! It is said to be smaller than C. bewicki, with the neck a third shorter, bill vermilion red with the dei trum (alone ?) black, and feet orange-yellow. Now no clear traces of any such characters can be seen on our two specimens from Possiette Bay. Swinhoe added that C. davidi was akin to C. coscoroba from South America, with which our two Swans have no likeness at all, being much more like C. bewicki (even adult), from which species they mainly differ in having the lores covered with small feathers and the bill much less black. However, as Pere David, who saw our two specimens shortly after their arrival in Florence (April 1880), recognized them at once as belonging to C. |