Page:The Zoologist, 4th series, vol 3 (1899).djvu/162

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THE ZOOLOGIST.

eggs laid by these birds, i.e. that they are conspicuous among birds for their tender affection for their mates, and that the eggs always hatch out male and female in the same nest." Why should this affection to their mates, or the fact that the two eggs usually hatch out male and female, cause them to lay only two eggs? As a matter of fact, I have frequently known the two eggs of Domestic Pigeons hatch out two males. In discussing Plovers, Mr. Davies makes the statement that in species in which the young are hatched fully formed and able to run, the egg is abnormally large for the size of the bird. Is this so? Roughly speaking, the Pigeon and Partridge are about the same size. The young Pigeon comes into the world blind and perfectly helpless, while the young Partridge is hatched well-formed and able to run; yet the Pigeon's egg is if anything rather larger than that of the Partridge. Again, the young of the Guillemot, which lays as big an egg in proportion to itself as almost any other bird, are hatched in a helpless condition. In Section VIII. I find:—"Owing to the cover afforded by the stems, the young (of Crakes and Rails) need not be so large when hatched as the young of the Plover, consequently the eggs are much smaller, and the hen can incubate a greater number." Why need they not be so large? I should think it would be of more advantage to a young Plover, hatched out in the open, to be small, than it would be to a young Water-Rail, which among the reeds and rushes would not be so easily seen. And then, is a newly-hatched Rail much smaller in proportion to the adult than a young Plover? Lastly, in Section IX., Mr. Davies writes of gamebirds:—"I should not be surprised to learn that they were originally less prolific before they were persecuted under the name of sport." It is well known that game-birds are not only not "persecuted" during the breeding season, but that they are perhaps better preserved than any other bird. Are not the large clutches produced by Pheasants and Partridges rather due to the almost semi-domesticated life they lead, and to the artificial feeding, where they are very strictly preserved. This would account for the least-preserved species, i.e. the Ptarmigan, laying the smallest clutch. But this is only a suggestion. As an example of a local variation in fecundity, I may quote the Yellowhammer, which hardly ever lays more than three eggs in Fifeshire. I hear that clutches of three are not uncommon in Gloucestershire also. Seebohm gives four to five as the usual clutch of this bird.—Bernard Riviere (St. Andrews, N.B.).

Some interesting Variations in the Plumage of certain Birds.—Chaffinch (Fringilla cœlebs).—Plumage white, with the exception of rather more than half the tail-feathers, upper tail-coverts, one primary and one or two secondaries in one wing; also a few feathers scattered over the head, neck, and wing-coverts, which are normal. Besides this there is a faint tint of canary-yellow on the back and secondaries, and the rump is de-