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FOSSIL REPTILIA OF THE 



distinct from the smaller kind from the Kimmeridge Clay, and propose to call it 

 Bothriospondylus robustus. 



It is matter of regret that, as yet, no teeth have been recovered from the Swindon 

 locality of the Kimmeridge Clay which are not referable to saurian genera previously 

 known and distinct from Bothriospondylus. But in the course of my work on ' Odonto- 

 graphy ' I received from an esteemed correspondent and ardent collector of fossils, Mr. 

 Channing Pearce, of Bradford, Wilts, a tooth from the Forest-marble near that town, 

 which I figured in the same plate 1 with that of Hylceosaurus? discerning in it an extreme 

 modification of the same type of Dinosaurian dentition. I reproduce the figures from the 

 ' Odontography ' in PI. IX of the present Monograph. 



The generic name of the Forest-marble Saurian so indicated was suggested by the 

 heart-shaped form of the crown of the fossil tooth (PI. IX, fig. 2). The crown, being 1 

 inch in length, 8 lines in breadth, and 5 lines in thickness, might well have come 

 from the jaw of a Dinosaur with dorso-lumbar vertebras of the size of that here referred to 

 Bothriospondylus robustus. The crown suddenly expands above the neck of the tooth, 

 thins to an edge along the fore and hind border (ib., fig. 3), and contracts to a point or apex, 

 which is sub-obtuse, being somewhat worn in the specimen figured. The enamel has 

 a peculiar character (of which a magnified view is given in PI. IX, fig. 5), being raised 

 into thin wavy longitudinal ridges with widish intervals where it was sculptured by 

 minute rugse. 3 The fang or root is cylindrical, coated with smooth cement ; the base of 

 this was preserved in the subject of fig. 4, PI. IX. I have not received any specimen of this 

 kind of tooth, nor any vertebra of the type of that figured in PI. VI, save from the Forest- 

 marble near Bradford ; but Professor Phillips has given a woodcut of a mutilated crown 

 of a similar sized tooth, 4 the best preserved margin of which swells out as in Cardiodon, 

 which was discovered associated in the ' Great Oolite ' with bones which will be subse- 

 quently shown to have the characters of Cetiosaurus. 



I feel the insufficiency of the present grounds for referring these teeth to any 

 otherwise defined species or genus of Dinosaur. But, if such heart-shaped teeth, with 

 other characters of Cardiodon, and especially if in situ in the jaw, or in portions of jaw, 

 should be discovered associated with vertebrae of the Bothriospondyloid type, it may then 

 be a question for the taxonomist whether Bothriospondylus should subside as a synonym 

 of Cardiodon ; unless, indeed, modifications of other parts of the skeleton than are now 

 known of Bothriospondylus robustus should be deemed to support a distinct generic name 

 {Marmarospondylus, e.y.). Meanwhile it seems to me more convenient to retain the verte- 

 bral designation of the genus, as I have next to show that such osseous generic characters 

 were manifested by still larger species from other members of the Mesozoic series. 



1 'Odontography,' PI. 75a, figs. 7, a, b, c, d. 2 lb., figs. G, a, b. 



5 ' Odontography,' p. 291. 



* 'Geology of Oxford,' 8vo, 1871, Diagram LXXXV, p. 253, "Tooth of Ceteosaurus:' 



