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 178 THE CONDOR Vol. XVI dent that the former number is that which more frequently occurs, although many European, and some American writers, who probably never saw the nest of this bird, allege the contrary. The eggs average three inches and three- quarters in length, by two inches and a quarter in their greatest breadth, and thus are considerably elongated, being particularly narrowed from the bulge to the smaller end, which is rather pointed. They are of a dull greenish-ochry tint, rather indistinctly marked with spots of dark umber, which are more num- erous toward the larger extremity" (vol. v, p. 168). This description would be excellent were it not for the fact that he has the usual number to the clutch wrong, the average size wrong, and the form, color and markings all wrong; otherwise it is pretty good. Coues says for this bird: "Eggs usually 2, 3.50x2.25, elongated and pointed, dull greenish-drab, with dark brown and blackish spots" (loc. cit., pp. 1049- 1050). This description might apply to some few eggs of Gavia immer, but by no means to them all. It is a dangerous practice to publish blanket descrip- tions of birds' eggs, as it is with respect to much else constituting biological materal. Reed says of the eggs of the Loon: "The two eggs which they lay are a very dark greenish brown in color, with black spots. Size 3.50x2.25" (p. 7). How about no. 11 of figure 52 of the present article ? The same author says of the eggs'of Gavia adamsi that it lays two eggs "size 3.60x2.25," and that in the case of this species "their nesting habits and eggs are precisely like the preceding (G. immer), except that the latter average a little larger," in all of which he is very probably correct. Of G. pacifica he also says "they lay two eggs of a greenish brown or greenish gray hue with black spots. Size 3.10xl.90" (loc. cit., pp. 9 and 10). The eggs here shown in fig. 53 are from Mr. Court's collection and came to me accompanied by the following data: No. 14, Gavia arct.ica. Collector (?); Fornea, Lapland, 14 June, 1909. Set 2. Set mark 20. This egg measures 3.18x2.00. No. 15. Gavia stellata, Oefusa, Iceland, 12 June, 1910 (35.49.2). I find the specimen to measure 2.80xl.80, which is Somewhat above the average size for this species. No. 16. Gavia stellata, Oefusa, Iceland, 2 June, 1910 (38.34.2), a speci- men which I find to measure 2.80xL80. All three of these are of a deep green- ish olive ground, deepest in no. 14, lightest in no. 15, with blackish brown spots distributed as shown in figures. There is no disposition for these spots to es- pecially congregate at the larger end in the case of any of these eggs, this being but slightly evident in nos. 15 and 16, but not at all so in the case of no. 14. Coues does not refer to either the color or the markings of the eggs of Gavia stellata; he simply says: "Eggs 2-3, 3.00xl.75." As to the ground color, I may say that there is a great similarity with respect to it among all species of loons of the genus Gavia. Variations in size and form, as found in the case of loons' eggs, is well shown for the Red-throated Loon (G. stellata) in fig. 54 (nos. 17-19). These in- teresting examples are also from Mr. Court's collection and bear the following data: No. 17, Oefusa, Iceland, 12 June, 1910 (38.92. 2), an unusual form of egg, which I find to measure 3.02xl.74. No. 18 was collected by A. W. Johnson on the 20th of May, 1874, at Or- fiord, North Iceland. There were two in the clutch, and I find it to measure 3.00xl.81.