twice as long as those of the peacock. The stork also feeds on frogs and garbage, while the peacock lives chiefly on grain, and in a wild state on pepper.

The third egg (c), which is rather less taper at the small end than that of the stork, and at the same time whiter, produces the common goose; while the fourth egg (d) produces the common eagle of this country, distinguished when full grown by its white tail. No two birds could differ more than the goose and the eagle in their dispositions and mode of life, even from the very time they are hatched. The young gosling, the moment it is out of the egg, can run about and feed itself with the utmost ease and agility; while the young eaglet is blind and helpless, and must be fed for many days by its parents. The gosling will plunge fearlessly into the first water it sees, and will swim about as dextrously as its dam, but if an eaglet were put into a pond it would inevitably be drowned. The goose feeds on grass, while the eagle would starve rather than swallow a mouthful of it: Spallanzani could not even by any art compel an eagle to taste bread, though a goose would consider this the greatest dainty it could have. Yet the egg of the goose is very similar in all respects to the egg of the eagle, and their slight difference would not be readily detected except by a naturalist who had paid attention to the subject.

The fifth egg (e), which produces a crocodile, though nearly of the same size as the other four, differs from them all in a few particulars, which, however, seem of too small importance, so far as external aspect goes, to indicate the extraordinary difference of the reptile from the birds. "An egg of a crocodile of fourteen feet long," says Count Lacépede, "killed in Upper Egypt in the act of laying, is preserved in the Cabinet Royale at Paris. It is whitish and of an oval figure, covered

by a shell similar to that of a pullet's egg, not quite so hard, but the film or membrane lining the shell is thicker and stronger. The long diameter is two inches five lines, and the short diameter one inch eleven lines." There is within the egg a yolk and a white, as in the eggs of birds; and "if broken into a bowl,” Dr. Drummond, says no eye could perceive the

difference."

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The young crocodile, like the gosling, takes to the first water it can find ; but, instead of living like the fowl, on plain vegetable diet, it preys upon every living thing which it can master and devour. Though the crocodile's egg also, as we have just seen from Lacépede, is similar in size to that of the goose (some are said by M. Bory de St. Vincent to be twice as large) the crocodile hatched from it often grows five times the length of a man, with a body as thick as that of a horse, and consequently many times the size of any of the birds produced from the other four eggs.

Eggs of the Ring Dove, the Boonk, and the Duck Bill.

The singular differences in the products of the five eggs of similar size, shape, and colour, just described, are more than paralleled in the three others figured below.

Figures of Eggs two-thirds less than the size of life. the ring-dove; b, egg of the boonk (Ardea minuta); c, egg of the duck-bill (Ornithorhynchus paradoxus).

a, egg of

The ring-dove, cushat, or wood-pigeon, whose egg is figured at (a), is a well-known bird of elegant form, of a fine blue colour, and having a plaintive note of poetical celebrity; but the little bittern or boonk, whose egg (b) is so similar to the ring-dove's, has its neck, bill, and legs long, its colour chiefly a shining green and rusty buff, while its voice is harsh and hollow. The differences are no less remarkable in the young when just hatched—the nestling ringdoves being blind, helpless, and fed by a substance similar to milk, prepared in the crops of their parents, and ejected into their mouths; but the young boonks the moment they escape from the shell, can run about and pick up food the same as a brood of chickens.

The third egg (c) has been but recently discovered ; the duck-bill having long been supposed to produce its young alive in some such manner as the kangaroo ; and the celebrated German anatomist, J. F. Meckel, even fancied he had discovered, in 1824, the teats by which it gave suck; and M. Blainville claimed some similar notions entertained by him in 1808. M. Geoffroy St. Hilaire, however, on examining the alleged milk glands, decided against the notions of Meckel and Blainville, and his opinions have been confirmed by the discovery of the eggs.

Mr. Holmes, an English collector, who resided some time in New Holland, was one day hunting on the banks of the Hawksburgh river, when he observed a duck-bill run from a sand-bank into the water. On examining the place, he found a hollow in the sand about nine inches in diameter, containing four eggs, which he took to England. Two of these are now in the Manchester Museum, and the other two are or lately were in the possession of Mr. Leadbetter of London. Professor Grant describes the egg as being

equal in diameter at each end, and consequently differing in this from most birds' eggs. The shell, besides, is

thin, brittle, slightly transparent, and of a uniform dull white. Dr. Grant and Mr. Yarrel think it is more like a lizard's than a bird's egg, but that it is somewhat different from both. At all events the difference is slight in comparison with the extraordinary difference of the duck-bill, and the ring-dove, or the boonk, whose eggs it so nearly resembles, as may be seen in the figures.

Comparative figures of the animals produced from the three eggs. a, Ring-dove; b, Duck-bill; c, Boonk.

The Mother Animal does not form her Eggs knowingly. The inference which I would draw from the facts connected with the formation of eggs, and the subse

quent evolution of animals within them in the process of hatching is, that the mother animal which produces them exerts no ingenuity or skill thereupon, their growth and progress being wholly carried on without her knowledge, and even without her consent. As very extraordinary skill, however, is displayed in the formation of an egg, it must be referred to some intelligent cause, otherwise we should have not only one but a countless number of effects-one, namely, for every egg-produced without any adequate cause. beginner may like to see a few details of the mode in which eggs are formed before they are laid, as a proof of the position that the mother bird or reptile knows nothing of their existence, much less exerts any skill in forming them. I shall follow the account I have given of this in the "DOMESTIC HABITS OF BIRDS."

The

In birds, the egg may be observed in the egg-organ under the form of a small yellow globe or sphere, frequently smaller than mustard-seed, but gradually increasing in size till it drops from its slender fastening, and falls into the egg-tube. The egg-organ contains all the eggs which are to be laid for several years, each egg differing from the rest in size as well as in composition and colour. The largest of them, which are destined to be first laid, are yellowish, while the rest gradually decrease in size, and are less and less yellow. The increasing weight of the egg, by stretching the slender attaching pedicle, probably attenuates the bloodvessels that supply it with nourishment, so as to greatly weaken and ultimately break it.

Before dropping into the egg-tube, there is no white nor shell, both of which are formed there by the addition of the glutinous substance called the white, and of the calcareous or limy substance constituting the shell. From ill health or accidents, eggs are sometimes