Page:Hardwicke's Science-Gossip - Volume 1.pdf/247

They may be mounted dry in cells, and are very pretty, though a mounted slide cannot compare with the sight I have described.

The binocular microscope will show both these objects to peculiar advantage.

The greatest care is needed to prevent damage to the specimens when collecting. A clean pill-box, with plenty of the native bark, is the best means to arrive at this end. The bark will keep them alive for some time, and the smallest specimens will not be so likely to escape by the interstices of the box as they would if the box were empty.

Can you inform me whore to find a full and accurate account of the metamorphoses of the Ephemera vulgata, or common Green Drake-fly, so well known to anglers? I have consulted several works, and not yet met with a satisfactory description of it. In one by Mrs. E. Cox, entitled "Our Common Insects," it is stated that the life of the Common May-fly (Ephemera vulgata) does not extend in its perfect state beyond five or six hours, being generally hatched about six o'clock in the evening, and dying before twelve at night. Now this is certainly not true with respect to the Green Drake-fly of the Irish lakes. I have seen it emerging from the water at all times of the day, and it lives for several days. The Green Drake-fly changes its skin, wings, legs, tails, and all, certainly once, and I believe two or three times during its short life, becoming at each change of a darker hue than before. As it comes to the surface of the water, it is of a beautiful yellow-green colour, and its wings in this state are not in the least injured by the water, as I have frequently seen it totally overwhelmed by the waves on a lake, and appear again sailing along as merrily as before. After changing its skin, however, the texture of the wing is much more gauzy, and cannot resist the water. On reaching the shore of the lake where it was born, it hides among the stones or bushes on the shore, and not until it has changed its coat does it become the active inhabitant of the air, whose graceful evolutions are so beautiful. Accompanied by swarms of its fellows, it then certainly enjoys life, now soaring aloft, anon dropping suddenly down, while often two or three together will come tumbling to the ground entangled by the long hairs of the tail. Presently some bird will make a dash through the crowd, and carry off a miserable captive, while the rest, heedless of danger, carry on their sport as before.—H. G. E.

Picket's work on the Ephemeridæ gives the most complete account of the metamorphoses of E. vulgata, together with figures of larva, &c. See also Westwood's "Introduction to the Modern Classification of Insects." The story of the single-day existence of insects of the family, as applied to the bulk of this species, is a pretty little romance, but by no means true, as some of them will live for at least a week. Nevertheless, in one or two instances their existence in the perfect state is certainly limited to a few hours. You are in error in supposing that E. vulgata, or any species of the family, changes its skin two or three times after they assume the winged form. When they first emerge, the whole creature is covered with a membrane, and, in this state, is termed a pseudimago. It then throws off this membrane, and is in every respect perfect, not moulting a second time. Some individuals (generally females) never even perform this operation at all.—R. McL.

It is my opinion that the eggs of birds are not necessarily lighted from being laid later. I remember myself and two school-fellows wished to see how many eggs a bird would lay. The example we took was the Robin Redbreast (Sylvia rubecula, Lath.). We found the nest with two eggs, in a wall in the muster-yard, Peterborough. We abstracted one, and for fourteen days successively did we take one egg out of the nest. The bird altogether laid sixteen eggs, all of which we preserved, and I remember we remarked that the last were equally as fully coloured as the first. The Robin's egg is often found quite white. W. D. S. does not mention whether the last egg in his nest was white, and I gather from his communication that it was only found lighter than the earliest laid ones. But what I want to show is that sometimes those earliest laid are the lightest. On referring to my egg-collecting book, I find that on May 2nd, 1861, I found a nest built in a large box hedge, in Little Gidding churchyard, Hunts, containing one pure white egg. I did not know what bird it was; but on May 9th I took the nest, containing five eggs. Three were white, and the other two were smaller, and of a faint blue, spotted like a linnet's. A sight of the bird showed me they were the eggs of the Mealy Redpole. Here, then, is a case of the lightest egg being laid first. I do not know for certain whether the other two white ones were laid next in order; they were slightly larger than the two ordinary coloured ones. Of these five, one of the albino specimens fell to the share of my bird's-nesting companion, while of the other two, one is in my own collection, and the other is in the collection of Mr. S. L. Mozley. Another instance of a white egg being laid first, came under my notice at Peterborough, when a school-fellow found a solitary white egg in a nest, and gave it to me, saying it was a linnet's. I remember the circumstance well, as that same day I received a linnet's egg no bigger than a pea.R. B. Sharpe.