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INSTRUCTIONS FOR PREPARING BIRDS' EGGS.

BY WILLIAM WOOD, M.D.

I Wish to say a few words for the benefit of those engaged in collecting oological specimens.

Twenty years ago, all eggs were blown with two holes—one at each end, and until within ten years most eggs have been emptied with two holes as above, or at the side. Very many of the eggs which I now receive in my exchanges are similarly prepared. At the present time no experienced collector ever makes but one hole to remove the contents of the egg, using a blowpipe in some form to accomplish this object. The following rules should invariably be followed.

1st. Prepare your eggs neat and clean. There is no excuse for having a dirty set of eggs where water, soap, and a tooth brush can be found. Some eggs will not bear washing, as the shell is so calcareous that the characteristic markings will wash away. There are, however, but few of this class, and I believe this peculiarity is confined to the water-birds. You can see it in any of the species (Smithsonian Catalogue) from G1.3 to 628 inclusive, and also in the eggs of the Grebes and Flamingo, and some others. Having once seen it you will never mistake it for anything else.

2d. Make but one hole, and that a small one in the middle of the egg—cover this hole, when the contents are removed and the specimen is dry, with gold-beater skin or the paper number indicating the bird. Use an egg drill or a pointed wire of four or six sides to make the opening.

3d. If the blowpipe does not readily remove the contents of the egg, inject water and shake the specimen thoroughly, then blow again, and repeat the operation until every particle of the egg is removed.

4th. If the embryo is too far advanced to remove through a moderate sized hole, blow out what you can of the liquid part and fill the egg with water, wipe it dry and put it away in a covered box in some warm place, and every 24 or 48 hours shake it well and remove what you can, and then refill with water. Repeat this operation several times, and after a few days the contents will become sufficiently decomposed to take away.

5th. After removing the contents of any egg cleanse the shell thoroughly. Fill it witli clean water and shake vigorously, blow out the contents and repeat the operation until the specimen is perfectly clean. This is particularly desirable in white eggs, as black spots will show through the shell after a time if the least particle of the egg or blood stains remains inside.

6th. Save all your eggs in sets—-that is, keep all the eggs each bird lays by themselves. This is the only way to form a correct knowledge of the eggs of any species, as a single egg, particularly of the blotched ones, frequently gives a very erroneous idea of the general markings—a very unsatisfactory representative of a set. For instance, in my collection are four eggs of the Buteo lineatus, found in the same nest, two of which are pure white and two blotched. It is not very uncommon to find great variations in markings in the same species and in the same nest.

7th. Keep a memorandum of the place and date of collecting each set of eggs.

8th. Use some kind of a blowpipe in preparing your eggs for the cabinet. The common blowpipe, with the addition of a fine pointed tip, will answer; yet it is a severe tax on the lungs and brain if you have many eggs to blow. I have many a time been dizzy and almost blind from overtaxing my lungs in this operation. 'Within a few years Mr. E. W. Ellsworth, of East "Windsor Hill, Conn., has invented a blowpipe which is operated by the thumb and finger, which works very perfectly and expeditiously. 1 would not be without it on any account. After using it for a time, and then letting it remain unused until the leather packing becomes dry, the instrument does not work satisfactorily to those unaccustomed to it. The remedy is simple. Take off the blowpipe and work the instrument submerged in a bowl of warm soap suds, when the leather packing becomes pliable and works as well as new. I have used the same instrument six years, and it works to-day as well as when new by following the above directions. The printed directions which accompany each instrument are intended to be a sufficient guide in case repairs are needed, and the maker can be referred to for any further information required.

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RELATIONSHIP OF THE AMERICAN WHITE-
FRONTED OWL.

BY ROBERT RIDGWAY.

I Wish to call the attention of .ornithologists to a paper recently published in the London "Ibis" (vol. ii, January, 1872), upon the relationship of the North American White-fronted Owl, known as "Nyctale albifrons Shaw," or "N. Kirtlandii Hoy." The author of the paper in question, Mr. D. G. Elliot, refers that bird to the N. Tengmalmi Gmcl., of Europe, with which species he also considers our N~. Richardsoni Bonap., to be identical. That both these opinions are erroneous, I purpose showing in the following remarks:

The little owl above mentioned, is a bird identical in all the details of form and size with the AT. Acadica Gmel., an exclusively North American form, which is scarcely more than half the size of the y. Tengmalmi, and cannot, b3- any means, be referred to the latter species. The birds which Mr. Elliot supposes to be identical with "Ar. albifrons" are merely the young of N. Tengmalmi, in a plumage analogous to that of the small North American species, but resembling the latter no further. Mr. Elliot is by no means the first to notice this plumage, for it has been long known to European ornithologists, and its relations correctly understood (see Naumann "Die Vbgel Deutschlauds," i, p. 500, pi. 48, figs. 2 and 3—where both the adult and young plumages are illustrated). Neither do I claim to be th« first to refer the " J\r. albifrons" to the AT. Acadica, as being its young stage, for Strickland in " Ornithological Synonymes" (i, 1855, p. 177) places the two together.

Being aware of the differences between the adult and young plumages of the N. Tengmalmi, and seeing a direct analogy in the characters of the Ar. Acadica and "N. albifrons" I suspected a similar relation between these two small North American forms; and in the course of my investigations of the North American Strigida? in the collection of the Smithsonian Institution I found other reasons for considering them old and young of one species. These reasons I present as follows :—■

1st. All specimens examined, of N. albifrons (including Hoy's

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type of N. Kirtlandii) are young birds, as is unmistakably apparent from the texture of the plumage.

2nd. All specimens examined of the N. Acadica, arc adults; I have seen no description of the young.

3rd. The geographical distribution, the size and proportions, the pattern of coloration (except that of the head and body, which in all owls is more or less different in the young and adult stages) and the shades of color on the general upper plumage, are the same in both. The white "scalloping" on the outer web of the alula, the number of white spots on the primaries and the precise number and position of the white bars on the tail, are features common to the two.

4th. The most extreme example of " albifrons" has the facial circle uniform brown, like the neck, has no spots on the forehead, and the face is entirely uniform dark brown; but —

5th. Three out of the four specimens in the collection have the facial circle composed of white and brown streaks {adult feathers) precisely as in Acadica, and the forehead similarly streaked {with adult feathers). Two of these have new feathers appearing upon the sides of the breast (beneath the brown patch), as well as upon the face; these new feathers are, in the most minute respects, like common (adult) dress of A. Acadica.

The above facts point conclusively to the identify of the Nyctale "albifrons" and N. Acadica. This species is easily distinguishable from the A. Tengmalmi which belongs to both continents, though the North American and European specimens are distinguishable, and, therefore, should be recognized as geographical races.

I give below a brief synopsis of the two species, and the principal list of synonymes belonging t§each : —

DIFFEUESTIAL CHARACTERS OF NYCTALE. Tengmalmi and AcaHica. Common Characters.—Tarsus longer than middle toe; tail slightly rounded, or nearly square: Ave outer primaries eniarginated on inner webs, their ends broad and bowed; 3d quill longest. Upper parts generally chocolate-brown, more or less spotted with white, the tail having distant transverse narrow bars of the same. Adult: Facial circle and forehead variegated with white; eyebrows and face grayish white; lower parts white with longitudinal spots, or stripes, of chocolate brown. Young: Facial circle and forehead plain blackish brown; eyebrows pure unvariegated, white; face plain dusky; lower parts without markings; the breast plain chocolate brown; the abdomen, etc., plain ochraceous.

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