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must have been of very great duration; for the conditions were such as to make evolution a slow process. The habitat of these primeval life forms, the oceanic waters, was of the greatest uniformity, even probably in temperature, and possessed no condition likely to provoke rapid variation. There was abundant space and probably abundant food, particularly in view of the minuteness and slight nutritive demands of these early animals, and the struggle for existence could not have been active. Though there were millions devoured hourly, there were trillions provided for the feast, so that no great tendency towards the preservation of favorable variations would have existed.

Yet, though the influences which favor evolution were not very actively present, they could not have been quite absent. The innate tendency to vary which all living forms possess now must have existed then, and the advantage possessed by the more highly over the more lowly organized forms could not have been quite wanting. Consequently, development of varying life forms must have gone on at some rate, and animals must in time have appeared much higher in organization than the simple forms from which they emerged.

And the variations which took place were radical in character. Variation in the higher recent types of life does not penetrate deeply. After ages of change a vertebrate is a vertebrate still. Millions of years of change do not convert a cat into something radically distinct from a cat. But in the primitive period the changes were more profound. Variation went down to the foundation plan of those simple forms and converted them at once into something else. A degree of variation which now would modify the form of a fish's fin may then have converted a monad into a new type of animal. Thus primitive evolution, working on forms destitute of any definite organization, may readily have brought into existence a number of highly different types of life. As the microbe, for instance, may through long variation have given rise to the two organic kingdoms of animals and plants, so the amoeba or other low animal form may have varied into the subkingdoms of mollusca, echinodermata, cœlenterata, etc., or rather into simple swimming forms

each of which was the progenitor of one of these great branches of the tree of life.

We are here in a realm of the unknown, through which we are forced to make our way slowly and uncertainly by aid of the clues of embryology, microscopic life conditions, principles of variation and development, and the known conditions of pelagic life. We can only surmise that, as the result of a long era of evolution, the simple primary forms gave rise to a considerable variety of diverse animals, still comparatively minute in size and simple in organization, swimming by means of cilia, and typified to-day by the swimming embryos of invertebrate animals.

As yet-if our hypothesis is well founded-no life existed upon the bottom of the seas, and the swimming forms were destitute of any hard parts capable of fossilization. But why did not some of these forms very early make their way to the bottom and begin life under the new conditions of contact with solid substance? And yet why should they have sought the bottom? Their food supply lay on or near the surface, the bottom of the shallow waters may have been unsuitable through the deposition of soft sediment, and the bottom of the deeper waters very sparse in food. And, more important still, they were quite unadapted to life on the bottom, and needed a radical transformation before they could survive under such conditions. If we look at the remarkable change which the swimming embryo of a star-fish or sea-urchin, for example, goes through before any resemblance to the mature form appears, we may gain some idea of the long series of variations which the primitive ciliated swimmers must have passed through to convert them into crawling or stationary bottomdwelling forms. Great as was the period needed to produce these type forms of life, another extended period must have been necessary to convert them into well adapted habitants of the solid floor of the seas.

(To be Continued.)

BIRDS OF NEW GUINEA (FLY CATCHERS AND

OTHERS).

BY G. S. MEAD.

Among the many kinds of Flycatchers (Muscicapida) inhabiting the Papuan Islands, while there is dissimilarity in so large a number of species, yet there are not those striking differences amounting almost to contrasts which characterize birds of greater size. Many species have been unnoticed by travellers and other writers; many exist only in cabinets and collections, labelled and ticketed, or at most given a few lines of technical summarization in catalogues. With the rank and file of birds anything more than this is impossible. Sometimes a particularly attractive specimen of Malurus or Rhipidura or Pratincola calls attention to itself, or mere accident brings an individual to the notice of the explorer or student.

Thus Mr. Wallace notes pointedly "the abnormal red and black flycatcher," Peltops blainvillii, so named by Lesson and Garnot many years since. It is a sprightly, highly colored bird with the predominant hues strongly contrasted and still further accentuated by spots of white on the head and beneath the wings. In flight this active little flycatcher presents in turn these conspicuous markings with striking effect. The red tint is a bright crimson spread over the lower back and tail coverts. The main color is a steely-green black covering with greater or less intensity the seven inches of total length. The genus is represented by this species only.

The same notable expedition to South Eastern New Guinea that secured the two beautiful prizes Cnemophilus macgregorii and Amblyornis musgravianus, discovered also a new species of flycatcher, viz., Rhipidura auricularis. It is described as having the "upper surface smoky gray; head brownish black; tail the same above and below; bill dark brown; legs black." The head is marked by black and white stripes, found upon the wings as well. Upon the chin, throat and breast similar

lines of unequal width are plainly drawn. The under parts are in general buff varied with black and gray. Dots and bars of white appear on the wings and tail. Its total length

is about six inches.

Rhipidura leucothorax, the Whitebreasted Fantailed Flycatcher, is much more widely distributed, being met with in different parts of New Guinea. The descriptive name here describes very imperfectly, for the breast is by no means entirely white as might be inferred; black is almost as prominent, alternating with the white which shows in spaces, though lower down it crowds the black into narrow bands or crescents. The general color of the bird above is brown, becoming dark upon the head, still darker over the bill. The wings are black, finished off with white spots. This is the appearance too of the tail feathers as well as of the under side of the wings. There are also white streaks and lines about the sides of the head and throat. Bill black above. Length 8 inches.

The family of Wood Songsters (Pacilodryas) are all small birds rarely exceeding 6.5 inches in total length. The coloration is in general black and white, the former greatly predominating. Poecilodryas albinotata at first sight looks in color not unlike those fine drongos, the Edolias. In this instance, however, leaving the disparity of size out of account, the gray is not nearly so uniform, a dull black and a deep black appearing on the wings, tail and throat including the side face. A patch of white meets the black on the sides of the neck. White again is seen on the abdomen and under tail coverts, becoming discolored along the flanks and sides of the body.

Pacilodryas papuana comes from the same region of the Arfak Mountains as the foregoing species. It is considerably smaller in size measuring only 4-5 inches inches in length, but of brighter color. This is a yellow, somewhat dull an becoming light brown on the wings and tail. Head and neck are darker than the body. A crescent of orange runs from the bill over the eye.

It is not un

Poecilodryas leucops shares the same habitat. like the preceding in coloration of the body but that of the head, nape and throat is entirely different. In this case it is

a dark gray, to gray on the neck with darker feathers over the eye. White marks the upper throat and chin and appears as a prominent spot in front of the eye. Total length nearly five inches.

From the Arfak Mountains also comes Pacilodryas bimaculata and from the same general region Pacilodryas hypoleuca and P. brachyura and P. cinerea. The first is conspicuously black and white, the former color preponderating very largely of course, while the white shows as bands and bars or stripes. It is most apparent on the lower parts where it may be reckoned as the ground color.

P. hypoleuca, the Whitebellied, is a rather larger bird, reaching the length of 6 inches. The general color is dusky above, relieved by white patches on the head. The same color covers the under parts set off by black on breast and throat. The last named-P. brachyura, the Shorttailed-is marked similarly with the tones rather deeper and clearer. Length 5.5 inches.

Monachella mulleriana or saxicolina, a Chatlike Flycatcher, is a lively little bird found as well in the south of New Guinea along the Fly River, as in the north among the Arfak Mountains. It is of grayish plumage above becoming nearly white on the rump and tail coverts; tail feathers and wings are dark brown. The head is also dark brown with a line of white over the eye. A spot of black lies near the bill. Below the colors are nearly those of the upper parts, that is, the body is a soft white, the wings brown. Bill and feet black. The sexes are alike in markings and size, the length being about six inches. They are both assiduous in the pursuit of insects, generally along streams on level spaces.

Monarcha or Muscipeta melanopsis, the Carinated Gray Flycatcher, has a ring of short black feathers about the large full eye, a discriminating characteristic, imparting with the strong prominent bill a singular appearance to this Australian bird. The entire throat and part of the face are also black, crowded upon by the soft slate color which becomes deeper over the rest of the body. The long tail above is dusky; below, as well as under the wings and on the abdomen, the color is a

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