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but occasionally with only four angles; in some species the sides are acute, in others rounded: the articulating surfaces are for the most part richly chased with floreal or radiated striæ, and grooved.' The arms in some species are very long and greatly subdivided, becoming extremely attenuated, and the ossicula proportionably minute. The exquisite beauty of the plumose encrinites when expanded on slabs of limestone and petrified by pyrites, is exemplified in several examples in the Case under review.2

LIGN. 23. PENTACRINITES HIEMERI; PART OF A GROUP ON LIAS LIMESTONE, FROM BOHL, WIRTEMBURG.3

(Nat. size.)

PENTACRINITES HIEMERI.-Wall-Case G.-On the large slab of Lias limestone affixed to the wall in the centre of this Case, is an exquisite group of thirty Pentacrinites, exposed in relief on the surface of the stone, in as perfect a state as if just

1 66 Pictorial Atlas," Pl. XLVII. The Briarean Pentacrinite is fully illustrated and described in detail in Dr. Buckland's Bridgewater Essay, p. 484.

2 "Pictorial Atlas," Pl. LI. LII.

This species was named and figured by M. Konig in his "Icones Fossilium sectiles," Pl. III., fig. 29, in 1826.

dredged up from the bottom of the sea. The reduced sketch of a small portion will serve to convey an idea of the elegant forms of these petrified zoophytes of the Jurassic ocean; the contemporaries of the Ichthyosauri and other marine reptiles, of which we shall treat hereafter. The Pentacrinites on this slab are for the most part entire; the peduncle being affixed to the base, and the column extending upwards in gentle undulations, and supporting the receptacle, which has the arms gracefully outspread in various attitudes. The structure of the receptacle, and of the arms, and the extreme delicacy of the finer tentacula made up of countless minute ossicula, are admirably shown in this unique and most instructive specimen.

This Case also contains illustrative examples of the Actinocrinites (Nave Encrinite),' Cyathocrinites (Cup Encrinite),2 Eugeniacrinites (Clove Encrinite), and several other genera.

Pentremites. One peculiar type of Crinoidea requires a brief notice, as it was supposed to be without arms, and to form a connecting link between the lily-shaped zoophytes and the sea-urchins. The Pentremites has a receptacle supported by a short pedicle, and composed of polygonal plates, divided by five perforated grooves or furrows, which are of an elongated petalous form, and converge in a rosette on the summit. The marginal longitudinal rows of minute pores are not however for the passage of soft membranous feelers, as in the ambulacra of echinoderms, as was formerly conjectured, but are channels for the transit of vessels that supply an infinite number of delicate simple tentacula, composed of extremely minute calcareous ossicula, as in the other Crinoidea, but not subdivided as in the Pentacrinites and Encrinites. These tentacula are directed upwards towards the vertex of the receptacle, and are supposed to have been organs for seizing and conveying food to the mouth.3

These Crinoideans abound in the mountain limestone, especially in some districts of the United States, where certain strata are distinguished by the name of pentremital limestone.*

1 "Medals of Creation," p. 324.

2 Ibid. p. 326.

3 See Dr. Fred. Roemer on Jointed Tentacles found on the ambulacral spaces of Pentremites, "Geol. Journal,” vol. v. p. 8.

"Medals of Creation," p. 327.

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FOSSIL REMAINS OF BIRDS-MOA OF NEW ZEALAND-NATIVE TRADITIONSHISTORY OF THE DISCOVERY-GEOLOGY OF NEW ZEALAND-MOA-BED AT WAIKOUAITI-OSSIFEROUS DEPOSITS IN THE NORTH ISLAND-BONE CAVES -FLORA AND FAUNA OF NEW ZEALAND THE APTERYX-MOA, DINORNIS-CRANIUM-BONES OF EXTREMITIES OF DINORNIS-FOOT OF DINORNIS-PALA PTERYX-CRANIUM-FOSSIL EGGS OF DINORNIS-APTORNIS -FOSSIL BONES OF NOTORNIS-DISCOVERY OF A LIVING NOTORNIS-FOSSIL PARROT-APTERYX-ALBATROSS-PENGUIN-DOG-SEALS-BURNT HUMAN

BONES-RETROSPECTIVE SUMMARY.

FOSSIL REMAINS OF BIRDS. Before describing the specimens which form the immediate subject of the present section, I would offer a few general observations on the occurrence of the remains of Birds in a fossil state, as introductory to the interesting phenomena that will shortly engage our attention.

Relics of birds are of extreme rarity in the mineral kingdom; throughout the immense series of paleozoic and secondary formations, the accumulated deposits of innumerable ages, no unquestionable indications of the existence of this class of highly organized beings have been brought to light.

Triassic Epoch.-In the Triassic or New Red argillaceous sandstones of the Valley of the Connecticut River, the remarkable foot-tracks described in a previous chapter, and of which there are illustrative examples in Room I. (ante, p. 13), seem to render it highly probable that birds of great size, and referable to numerous species and genera, existed during the period when the Triassic strata of the

United States were deposited; but, unfortunately, notwithstanding the preponderance of the evidence in favour of the ornithic origin of these mysterious imprints on the rocks, the only certain proofs-remains of the skeleton—are still wanting: no bones of animals of a higher class than fishes and reptiles having been discovered.

Oolitic and Wealden Epochs. — In the vast fluviatile formation, the Wealden of the South-East of England, which abounds in the remains of terrestrial plants and reptiles, numerous fragments of bones of such tenuity as to show that they belonged to animals capable of flight, have from time to time been collected, since my discovery and announcement, in 1822, of the occurrence of supposed bones of birds in the strata of Tilgate Forest. Some of the bones in my collection were regarded, by Baron Cuvier, and subsequently by other eminent anatomists, as unquestionably those of birds; one specimen especially was conceived to be decisive of the question, for Professor Owen supposed it to be the tarso-metatarsal of a wader, with the oval cicatrix for the attachment of the hind toe; but this fossil ultimately proved to be the distal end of a humerus.

Later observations have shown that it is probable all the presumed ornithic remains from the Wealden belong to Pterodactyles, as well as those from the oolitic strata of Stonesfield. The microscopic examination of some of the thin cylindrical bones from each of these formations, by Mr. Quekett and Mr. Bowerbank, has, however, revealed a structure which these gentlemen regard as exclusively ornithic.

Cretaceous Epoch.—In the Chalk formation many osseous remains of animals capable of flight, as indicated by the articulations, and the extreme tenuity of the walls of the bones, have been obtained from Burham quarries, near Maidstone. Some of these specimens have been figured and described by Professor Owen as those of a bird allied to the Albatross, under the name of Cimoliornis Diomedeus;1 but the occurrence in the same strata of the skull, jaws with teeth, and other unquestionable bones of gigantic Pterodactyles, and the absence, in the fossils, of osteological characters exclusively

1" British Fossils, Mammals, and Birds,” p. 545; and Dixon's “ Fossils of Sussex," p. 403.

ornithic, support the conclusion that these also must be ascribed to flying reptiles.

The enormous size of the bones, however, indicating an expanse of ten or twelve feet from the extremity of one wing across to that of the other, and suggesting the idea of a flying reptile equal in magnitude to the fabled Roc of Arabian story, threw doubts on the pterodactylian nature of these remains; but Mr. Bowerbank has lately obtained from the same quarry portions of an upper jaw with teeth, so large, that the head of the creature to which it belonged could not have been less than sixteen or seventeen inches in length;1 a size proportionate to that of the bones of the extremities above alluded to.

But although no certain vestiges of birds have yet been discovered in the Wealden or Cretaceous formations, I think there are good reasons for supposing that such remains will sooner or later be brought to light: for independently of the ornithic structure detected by the microscope, I had from the Wealden a portion of an ulna, on which there was a row of distinct eminences, as in birds, for the attachment of the large wing-feathers; this specimen was in the collection purchased by the Trustees of the British Museum.

Tertiary Epoch. In the most ancient tertiary strata, bones of several genera of birds occur; in the Sub-Himalayan deposits they are associated with relics of the extinct proboscidean mammalia of India : in those of the Paris Basin, with remains of Palæotheria, &c. From the miocene and pliocene lacustrine deposits of Auvergne, bones, and even egg-shells, of several kinds of aquatic birds have been obtained.

The ossiferous caverns which abound in the bones and teeth of numerous carnivora, often contain the remains of existing genera of birds. In the Cave of Kirkdale, Dr. Buckland discovered bones of species of raven, pigeon, duck, lark, snipe, &c.2

The fossil bones of birds, however, even in the most recent deposits, were of such rare occurrence, as to be ranked by the

1 Described by Mr. Bowerbank under the name of Pterodactylus giganteus. Proceedings of the Zoological Society.

2 See "Reliquiæ Diluvianæ," p. 34; "Medals of Creation," Art. "ORNITHOLITES," p. 795.

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