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six months, afterwards using the pouch only for shelter, and occasionally feeding.

In the Philosophical Transactions for 1837, the memoir on the brain of the Marsupialia was published, recording the absence of the corpus callosum. This was followed by the articles "Monotremata" and "Marsupialia" in the 'Cyclopædia of Anatomy and Physiology,' showing, among other characteristics, a similar cerebral structure in the Ornithorhynchus and Echidna. Two papers in the Zoological Transactions, "On the Osteology" and "On the Classification of the Marsupialia," completed the grounds for forming a primary group or subclass of the Marsupial and Monotrematous Mammals, for which the names Implacentalia or Lyencephala were proposed.

Pursuing his researches into the correlations of the cerebral with other systems of organs in the mammalia, Professor Owen was led to associate the Cuvierian orders or tribes, Edentata, Rodentia, Insectivora, and Cheiroptera, into a second "subclass" called Lissencephala, from the smooth unconvoluted character of the cerebrum. The Cetacea, Pachydermata, Ruminantia, Carnivora, Quadrumana form a third subclass-Gyrencephala, or with convoluted brains. The superior development of the human cerebrum, zoologically marked by its extension over and beyond the cerebellum with concomitant structures in the posterior lobe, called in human anatomy "hippocampus minor," etc., afforded the characters of a fourth equivalent group in the classification on the brain-system, which is called "Archencephala." Cuvier, pointing to the "feet" as fitted for erect stature, and "hands" for perfect manipulation, affirmed them to be peculiar to man, and founded thereon the order Bimana. But modified homologues or rudiments of the thumb, great-toe, hinder lobe of the cerebrum, etc., occur in certain species of the lower group approximating the higher one; to the objection to his cerebral classification, that some of the highest Gyrencephala possessed what might be called rudiments of a "hippocampus," etc., Professor Owen replied by contrasting those parts as they existed in the gorilla, chimpanzee, etc., and in the human subject. It was as absurd to suppose that he denied the existence of the parts which Tiedemann, Vrolik, and Kuhl had pointed out, as that Cuvier denied the existence of the homologue of the great toe in the orang. The graduation of structures in the chain of living beings affords similar grounds of

attack against all systems of classification, which, nevertheless, are indispensable to the comprehension of the science of animals. and plants.

In 1847 Professor Owen published the facts and reasons for a re-distribution of the Pachydermata and Ruminantia of Cuvier into the Ungulata with hoofs in equal number (Artiodactyla), and into those with hoofs in unequal number (Perissodactyla). The Artiodactyles were subdivided into ruminants and non-ruminants, numerous extinct species being shown to have filled up the intervals that now exist; while in like manner the Horse tribe, the Solipedes of Cuvier, were shown to be more closely allied to the tapir and rhinoceros by other intermediate Perissodactyles of geological ages than would appear by the examination of living species only.

In regard to the Quadrumanous family, which makes the nearest approach to man, but little was known, and that imperfectly, at the close of Cuvier's labours. The orang-utan was placed at the head of the order, and both this and the chimpanzee were known to the great naturalist only in their immature condition. The osteological and dental characters of the adults of both forms were made known by Owen in a series of memoirs in the Zoological Transactions for 1835 and 1836, proving that the chief characters supposed to approximate these animals to man are transitory, and peculiar to the young state of the animal with deciduous teeth. The chimpanzee is placed above the orang; both are characterized in the adult state by a sexual distinction in the teeth. A smaller species of Bornean orang (Pithecus Morio) is defined: the larger one (Pithecus Wurmbii) had been supposed, from its huge canines and low facial angle, to be a baboon.

In 1847 Professor Owen's opinion was sought by an American missionary at the Gaboon, as to the skull of a large baboon-like quadrumane, of which Dr. Savage transmitted a drawing: in this was recognized a new species allied to the chimpanzee. It was described by Dr. Savage under the name of the "Gorilla," which name Professor Owen adopted, though aware of the improbability of its being the ape so called by Hanno. In a series of elaborate memoirs in the Zoological Transactions and Proceedings, from 1848 to 1862, the osteology, dentition, with the external and other characters of the gorilla, are described by Owen, and compared with the chimpanzee, Papuan, and Negro. Our anatomist con

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cludes, in opposition to Professors Isidore Geoffroy St. Hilaire and Wyman, that the gorilla ranks above the chimpanzee. The rich collection brought to London by M. du Chaillu illustrated the characters of the female and young of the gorilla; and through Professor Owen's consistent support and advocacy of M. du Chaillu, the striking and instructive specimens of this rarest and most interesting of brute-beasts have been secured for the British Museum, where they are now displayed.

With regard to the class of Birds, we may refer to Owen's monograph on the anatomy of the Toucan in Mr. Gould's work on the Ramphastidæ, to the paper on the anatomy of the Hornbill (Buceros) in the Zoological Transactions, vol. i., and to the two elaborate monographs on the anatomy of the Apteryx in the same Transactions. The incidental notices of the organization of the larger struthious birds in the comparative part of these papers, and above all the accessions to the same wingless order which we owe to the discoverer of the Dinornis and Palapteryx, supplied the grounds for separating from the Grallæ, or order Échassiers of Cuvier, the species that therein form the family "Brevipennes." Other modifications of the Cuvierian system, and an inquiry into the grounds for a binary division of the class, according to the condition of the newly-hatched young, e.g. into Aves altrices and Aves præcoces, will be found in the elaborate article Aves, communicated to the Cyclopædia of Anatomy and Physiology, in 1836.

Perhaps none of Professor Owen's researches on fossil remains have excited more general interest than those to which we are indebted for a knowledge of the gigantic struthious birds of New Zealand, the first paper on which, entitled "Notice of the Fragment of a Femur of a Gigantic Bird of New Zealand," read November, 1839, was published in the first part of the third volume of the Zoological Transactions. In this paper the author concludes "that there existed, and perhaps still exists,* in those distant islands, a race of struthious birds of more colossal stature than the ostrich or any other known species;" and so confident was Professor Owen of the soundness of his inductions, that he boldly added, "so far as my skill in interpreting an osseous fragment may be credited, I am willing to risk the reputation for it on this statement." Ample confirmation came to hand in 1843, and has continued to arrive.

*We trust Mr. Frank Buckland's zeal may be rewarded by the ample fulfilment of this prediction.

Six or seven successive monographs have been devoted to the restoration of species of Dinornis, Palapteryx, Notornis, Aptornis, and other extinct birds of New Zealand. The Museum of the College of Surgeons is enriched by a restoration of the Dinornis giganteus; that of the British Museum by the reconstituted skeleton of Dinornis elephantopus, perhaps the most remarkable of all these feathered giants.

In palæontology Owen's labours have not been less important than in anatomy and zoology. In 1842 he communicated his first Report on British Fossil Mammalia, and his second and concluding Report on the same class of extinct animals; both at the instance, and with the aid of grants, of the British Association for the Advancement of Science. The matter of these Reports was incorporated with kindred researches, and beautifully illustrated in the History of British Fossil Mammalia and Birds,' 8vo, 1846. The Coryphodon there indicated by a small fragment brought up from a deep well sunk in the London clay, at Camberwell, has now been almost wholly restored by fossils from the older eocene of France; but this fragment included an entire tooth. Cuvier required a molar tooth, or a characteristic bone with the articular surface complete, as the basis of his restorations, which at the time appeared so marvellous. When the fragmentary fossil relics brought from Buenos Ayres by Darwin in Admiral FitzRoy's Expedition in 1837, were confided to Professor Owen, not having in many instances the requisite Cuvierian essentials, he brought the microscope to bear upon the portions of teeth, and by the characteristic modifications of the internal structure of seemingly valueless fragments, obtained the knowledge which his great predecessor could only predict from a perfect specimen. In the attempt to reconstruct these fragmentary South American fossils, in some cases Mr. Owen had not even fragments of teeth to build upon, nor a bone with the articular extremities. He then resorted to the grooves channelled in the bone by blood-vessels, or the perforations by nerves, and other previously neglected or unthought-of means, which were attended with paramount success. In this way he recognized the affinity to the llama of the long-necked, perissodactyle fossil Macrauchenia from a few neck-bones found petrified on the cliffs of the barren shores of Patagonia; and made out almost entirely from a study of the nerve-canals in a single fragment of a skull, the extinct Glossotherium. Unsuspected affinities of

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Rodentia to Ungulata were brought out in the restoration of the Toxodon; but perhaps the most important principle laid down in the volume on the Fossil Mammalia of the Voyage of the Beagle,' 4to, 1838, was the conformity of the types of extinct with those of the existing mammalia characterizing the South American continent.

About the same time an analogous collection of fossil remains were submitted to Owen by Colonel Sir Thomas Mitchell, from bone-caves and freshwater deposits of Australia; these were described in an Appendix to Sir Thomas's Three Expeditions to New South Wales.' In it the genus Diprotodon was founded on a single fragment of an incisor-tooth. To this gigantic marsupial Owen shortly after added the Nototherium, Thylacoleo, Phascolomys gigas, etc. He sums up the whole of his discoveries in this field, and their general bearings in his "Report on the Extinct Mammals of Australia, and on the Geographical Distribution of Pliocene and Post-pliocene Mammals in general," communicated to the British Association in 1844.

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It would be too long to cite even the titles of the numerous papers, reports, and works in which the results of Owen's researches into the mammalian and reptilian classes of fossils are recorded. We may allude to the close observation and reasoning by which the mammalian characters of the oolitic Amphitheria and Phascolotheria, and of the supposed Neocomian Basilosaurus, were established in the sixth volume of the Transactions of the Geological Society,' 2nd series; to the elimination of the parts of the Glyptodon from those of the Megatherium, with which they had been confounded; to the reconstruction of Glyptodon and Mylodon now the ornaments of the Muscum of the College of Surgeons; and to the illustrations of the adaptation of the skeleton of Mylodon and Megatherium to the task of uprooting trees, fully developed by Owen in his 'Memoir on the Mylodon,' 4to, 1842, and the grandly illustrated work on the Megatherium, finally completed and issued in 1862, 4to.

The results of a general survey of all accessible specimens of British fossil reptilia appeared in two Reports, communicated to, and published by, the British Association; the first in their volume for 1839, the second in that for 1812. The matter of these Reports, and of subsequent discoveries, has been methodized into a systematic History of British Fossil Reptiles,' of which six parts

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