The Mesosauria of South Africa / by H.G. Seeley.

  • Harry Govier Seeley
Date:
1892
Catalogue details

Licence: Public Domain Mark

Credit: The Mesosauria of South Africa / by H.G. Seeley. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

    4/28 (page 586)
    580 The Mesosatjria of South Africa. By H, G. Seeley, Esq., E.R.S., F.L.S., F.G.S., Professor of Geography and Lecturer in Geology in King’s College, London. [Plate XVIII.] §1- §2. §3- §4. §5. §6. Contents. Introduction The Kimberley specimens of Mesosaurus pleurogaster. The Mesosaurus tenuidens (Gervais) from Albania ... The Mesosaurus in the Albany Museum The Relations of Mesosaurus with Stereosternum Classification of the Mesosauria Page . 586 . 587 . 591 . 597 , 598 . 604 § 1. Introduction. Prof. Gervais in 1865 described under the name Mesosaurus tenui- dens the remains of a small reptile from Griqualand, South Africa, which had been brought to France more than thirty years before. It is preserved in a slab which shows the skull and anterior portion of the skeleton. As with other vertebrate remains from South Africa, its exact geological age is unknown. The author states' that the animal was a little larger than the Ocellatcd Lizard, and has many affinities ; resembling in some characters terrestrial types of reptiles, while in other characters it approaches Simosaurians and Plesiosaurians. Its cervical vertebrae have some resemblance to those of Crocodiles. The lower jaw recalls in a general way Croco- diles and Plesiosaurs. The dorsal vertebrae are rather elongated and comparable to those of Homoeosaurians and of Teleosaurs. The ribs are stronger than in any known reptile except Pachypleura, and are arranged as in that genus. They have much the same rela- tion to the ribs of other reptiles that the ribs of Sirenians have to those of other mammals. The sternal ribs, identified by Cope, were regarded as annelid tracks. The scapular arch is compared to those of Crocodiles and Plesiosaurs ; but the scapula and coracoid are anchylosed. The humerus is that of a Plesiosaur or Simosaur, with an eut-epicondylar perforation, like that seen in Varanus and certain mammals. The forearm and hand are of less aquatic type than in Plesiosaurs, and approach the terrestrial type; but the ulna, unlike that of terrestrial reptiles, has no olecranon. The animal is compared to Lariosaurus, Machrimosaurus, and Pacliypleura, but is distinguished from them by the form of the head, the teeth (which are exceptionally long), and the number of cervical vertebrae, which were stated to be seven, with two which are intermediate in cha- racter between the cervical and dorsal. * Gervaie, ‘Zoologie et Pal^ontologie G6n6rales,' 1867-69, p. 223, pi. xlii.