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the æpyornis (Epyornis) of Madagascar, and its enormous eggs, capable of holding two gallons of water. These and the recently extinct moa (Moa), and notornis (Notornis Mantelli), of New Zealand, are sufficient to show the interest of the relics from alluvial strata, and the necessity of a better knowledge of their contents. The search after the early traces of Man will no doubt be ere long prolific in results to the naturalist, as well as to the anthropologist; and the knowledge of the animals and plants with which the pristine races of our kind were surrounded will be a subject of the greatest interest.

The above enumeration gives all the cases of bird-remains from every part of the world that are at present known; and as it is the full account of a whole class of animals, it shows very decisively the positive imperfections of the geological record as at present eliminated.

When Darwin first made the bold assertion that there were great gaps in the geological history, there was some disposition in scientific quarters to meet his assertion with scornful denial. Geologists had so prided themselves on what they had done, that they had never thought about what had been left undone; and it was soon found when reflection was turned to the subject that it was impossible for such

a statement to be gainsaid. Attention has now been forcibly drawn to the fossil remains of this particular class by the discovery of an extraordinary bird in the lithographic slates of Pappenheim. This creature, so beautifully preserved that even the impressions of the feathers in the stone are retained, was first made known to the world as a supposed "feathered reptile," and has been lately purchased for the British Museum, and admirably described by Professor Owen. (Fig. 14.) As accounts of this extraordinary fossil have appeared in almost every

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daily and weekly journal, we need do no more than briefly refer to its prominent points, and the history of its discovery. In 1861, M. Andreas Wagner communicated to

the Academy of Munich an account of the discovery of a fossil with divergent fans of feathers, of which he had been informed by M. Witte, the mayor of Pappenheim. Wagner, who was very ill at the time, in fact dying, never saw the specimen, but concluded, from the description he had received, that the remains must be those of a reptile, and named it the Griphosaurus. The familiar presence in the same beds of lithographic stone of flying reptiles, the Pterodactyles, aided Wagner's error, and a furore was created in the scientific world. After Wagner's death, the fossil was purchased from M. Häberlein, of Pappenheim, in whose collection it was, for our national collection,not under the idea, however, that it was a feathered reptile, for both Professor Owen and Mr. Waterhouse were satisfied of its ornithic nature.

Bird-remains, so perfect and so extraordinary, and from so ancient a stratum, were, however, a desideratum of the highest scientific importance, especially when the creature possessed the extraordinary character of a long vertebrate tail.

After Professor Owen's elaborate and accurate examination, no doubt can remain as to its bird-like nature-the presence of a furculum or "merrythought," and the "perching" form of the leg and foot, with many other less prominent features, are sufficient to establish this. But it will be desirable to notice some of those abnormal characteristics which render it so very remarkable in a zoological point of view, and which make it imperative to show distinctly that it does not possess reptilian characters. The powers of flight possessed by the Pterodactyles, the long vertebrate tail of one of them-the Rhamphorhynchus— found in the same strata with the Archeopteryx, and the general tendency of naturalists to seek for, and perhaps too readily to accept, any evidences, supposed or real, of a transmutation of species, have in the present case fostered the original idea of a "feathered reptile," and led to a wide-spread readiness to accept the, as yet, untenable doctrine of the transmutation of flying reptiles into birds.

Flight is not the peculiar property of birds alone, although they possess it in a degree of perfection unknown to any other animal, and although through it they are clothed in garments of such exquisite delicacy and beauty; so essentially is it the prominent idea of their whole structure, that we have not only universally come to regard it as their special attribute, but as universally to view the bird as the typical and bodily expression of the idea of flight. Still, the bat flies, and the flyingsquirrel (Pteromys) on outspread wing-sails shoots from bough to bough. Yet both are mammals; in the one the long fingers of the fore-arms spread out the side-skin into wings (Plate XVII., fig. 8); in the other it is but the same loose expanded skin that

forms the sail. But the structure of the bird's wing is altogether different. The humerus bends back from the scapula (Fig. 6), the ulna and radius form the remige of the wing to which the quillfeathers are attached; while the carpals and metacarpals of the second and third digits form the pinion, and the carpals and metacarpals of the fourth digit are anchylosed together and form a little undeveloped finger of bone at the joint of the wing between the remige and the pinion. In the wing of the Pterodactyle (Fig. 7) the little finger is made to do duty as the yard to spread the sail of leathern skin, while the rest of the fingers provided with strong hooked claws extend beyond the wing-joint as clutches for the monster to hang on by, as bats and vampires do, to points of rock or boughs of trees.

The wing of the Archæopteryx has one or two claws (Fig. 15), or rather hooks, but so have recent birds. The Parra jacana, the Palamedea, the "spur-winged goose," the Syrian blackbird, are all examples. These claws-and in the Archæopteryx there might be, Professor Owen thinks, possibly three-are particular developments of those digits which ordinarily in birds are modified and disposed to form the pinion of the wing, and are not to be necessarily considered as in any way equivalent to the wing-finger of the Pterodactyles. They may have been used as hooks, but that they were so is not certain; and in the spur-winged birds the spurs are generally pointed, and usable apparently only as weapons of offence or defence. (See the Chaja Screamer, Plate XVI., fig. 10.) The reason, it is said, that "possibly the Archaeopteryx had these two or three wing-hooks, is that these bones are displaced in the slab, and therefore may have been washed together. There is reason, however, to think that other osseous remains lying near to the hooks may be carpal bones.

FIG. 15.

The form of the foot in the Archeopteryx is also decidedly that of a bird (Fig. 11). Its specialities may perhaps be best seen by a comparison with that of the Falcon (Fig. 13), or some other strong-footed, retractile-clawed, raptorial bird, between which class and the Perchers, the Archaeopteryx will probably take zoological rank. In the Geologist for January last I pointed out the particular organs indicated by a cast of the brain-cavity of the skull, which has been remarkably preserved in the stone; and I would here draw attention to another portion of this wonderful fossil, which has hitherto received no published notice.

While the Archaeopteryx slab presents us with the bones of the wing, the furculum, the ribs, the ischium, the numerous vertebræ of an extraordinary and long tail, into which the feathers were set in pairs,-while the imprints of these feathers

are, as well as those of both wings, most delicately preserved, Professor Owen, in his wonderful description before the Royal Society, made no mention of the head; and that portion was believed to be absent from the block. I had, on the first occasion of seeing the reverse of the Archæopteryx block, noticed a ring of spar, which I considered as representing a part of the skull. A friend, to whom I showed it, differing in opinion, I did not press the point. Moreover, the block itself was under examination by Professor Owen at the time; and common courtesy demanded that I should not use any facilities afforded to me by the officers of the national collection in anticipation of the labours of so able and so competent an anatomist.

Some time after the reading of Professor Owen's paper, when Mr. John Evans,-struck with the resemblance of the concretion that had been formed within the ring of spar above noticed, to the two lobes of the brain, — made a cast of the braincavity of a crow's skull, my attention was re-directed to the subject, and I made a careful comparison of a bird's brain with the Archeopteryx concretion, and pointing out the actual parts of the brain shown in it, demonstrated (I suppose to the satisfaction of paleontologists, as no one has disputed my conclusions) that this cast represented the fossil brain of that creature. This evidence was confirmatory of the previous conclusions of Professor Owen, as to the ornithic nature of the fossil; for the characteristics of reptilian brains are so distinct from those of birds, that no tyro in anatomy could mistake the differences. If, therefore, "the feathered reptile" theory had any basis in fact, the Archeopteryx brain should have presented a pterodactylian, or reptilian organization, and not have agreed in every typical feature with the brain of a common bird.

Since the discovery of the brain my attention has been drawn to some very indistinct portions of crystalline substance on the surface of the slab, representing bone; for all the bones of the Archæopteryx are changed into calcareous spar, in which four or five little sparry points are to be seen. Mr. Evans, we are told, first detected these points, and assumes they are, or may be, teeth. From this he has inferred that the portion in question might be the jaws of the Archæopteryx. Mr. Davies, of the Paleontological Department of the British Museum, differed from this view, and pointed out to me specimens of fish of the same geological age as the Archæopteryx, with which he thought they agreed in form; regarding the bones with which they were associated as the maxillaries, &c., of a fish's head. As I was not, for zoological and anatomical reasons, disposed to believe that a bird's beak could be armed with teeth, I was inclined to accept Mr. Davies's explanation.

The "fish-head" theory did not, however, rest easily on my

mind. I could not conceive why a fish's head should be mixed with the Archeopteryx's bones, instead of its own. The principle of taking another man's hat when you have lost yours did not apply. The fossil, like Conrad Gesner's "dragon," or the Japanese monster in the Field window in the Strand, was not made up of the head of one thing, the body of another, and the tail of a third. It was not a compound of the body and legs of a bird, with the tail of a Ramphorhynchus and the head of a fish, but was a veritable fossil undoubted from end to end and top to bottom. How a fish's head could get there, without any other trace of its body, fins, bones, or tail, was puzzling-not even a scale; and the lepidoid fishes-to which order, if any, this head, if it were one, must be referred-had thick, hard scales, which would not easily decay, and which could not, if there were any in the stone, be overlooked. Nothing but the head! seemed so strange that I was induced to make a careful comparison of the supposed fish-head with the inverted beak of bird, to which a close inspection had led me to think it bore a resemblance.

Selecting purposely the skull of a raptorial bird, by the kindness of Mr. Geo. Gray, the opportunity of comparing it with the skull of the Aquila Bonelli has been afforded me; and, as I believe, with the probability of a useful result. I speak diffidently, because these particular bone-remains, so obscure as to have passed under the keen and scrutinizing eyes of the Superintendent of the British Museum without detection of their nature, are not data upon which one could be at all disposed to speak reliantly. Still, however, having come to the conviction that these shattered and altered remains (PlateXVII., figs. 1, 2) may be the veritable beak of the Archaeopteryx, it is but right to make known the ground for that opinion.

Suppose, then, that the beak with the nasal bones, which are thin at the part joining on to the cranium, had rotted off, and had fallen, or been washed backward on to the mud, where they rested in an inverted and upturned position, ultimately by the pressure of the stony matter above becoming flattened and distorted. In this position the under surface of the fore part of the head would be seen; and supposing the lower mandible to be absent, we should have this enigmatical part of the fossil displaying the edge of the pre-maxillary and the indented impression of the upper side of the bill, a pterygoid plate on each side, and the two palatals either anchylosed together, or pressed up flattened in the inner space. But seemingly the lower mandible remains, with its rami pressed down over the pterygoid plates, to the shape of which it nearly conforms; so indistinct, however, is this portion, that it will be very difficult to assure oneself what it is.

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