748 REPORT— 1893. 



8. 0)1 some Vertebrate Remains not hitherto recorded from the Bhcetic Beds 

 of Britain. Bij Montague Browne, F.G.S., F.Z.S. 



Plesiosaurus rostratus, Owen.' 



In the autumn of 1890, when visiting Aust OlifF for a day, the writer found 

 some interesting vertebrate remains in the celebrated Rhtetic ' bone-bed ' there. 

 Amongst others was a large tooth which there was little difficulty in referring to 

 the so-called Termatosaurus albertii, a description of which, with figures, was pub- 

 lished by Plieninger - in 1844, and by Quenstedt^ in 1858. This type of tooth has 

 been queried subsequently, indeed, by Quenstedt himself,* as pertaining to a Plesio- 

 saurus, but the species has never been determined. Since 1890 the Rhsetics of 

 Aust Cliif, of Westbury-on-Serern, and of the Spinney Hills, Leicester, have 

 yielded to the Avriter teeth of the same character, and he has recognised similar 

 specimens, either unreferred or attributed to Termatosaunts alhertii, in the British, 

 Bath, Bristol, Cardiff, Gloucester, and Leicester Museums, the Museum of Prac- 

 tical Geology, Jermyn Street, and some from the Rhsetics of Stanton-on-the- Wolds, 

 Nottinghamshire, collected by Mr. E. AVilson, F.G.S. 



During a visit to the Geological Department at South Kensington the writer 

 succeeded in referring them, with some certainty, to Plesiosaurus rostratus, and 

 considered that, could some vertebrae of the same Plesiosaurian be found, this 

 would furnish corroborative evidence. On a second and third visit to Aust, there- 

 fore (in 1891-92) — both of several weeks' duration — no pains were spared in search- 

 ing for vertebrae, with the result that several specimens were procured ; and since 

 that time many have been acquired, by purchase and presentation, from the same 

 beds, and others have been recognised as Rhretic specimens in the British, Bristol, 

 and Gloucester Museums ; whilst subsequent visits to the British Museum, and an 

 examination of the whole of the vertebrae there definitely assigned to Plesiosaurus 

 rostratus, have resulted in the conviction that the Rhaetic Plesiosaurian vertebrae 

 are specifically identical. It is noteworthy also that one of the specimens in 

 the writer's possession — a cervical vertebra —might have been used for the figure 

 given by Owen ^ on tab. x. fig. 1, and the description tallies well, especially on 

 p. 23, where is stated the fact, patent on all the Rhaetic specimens possessed or seen 

 by the writer, that ' the fore surface of the centrum presents a slightly fibrous 

 character, not so smooth as in some other species, nor so irregular as in the Plesio- 

 saui-us rugosus, for example ; ' and again, on pp. 24, 25, ' The sides of the neural 

 spines of these vertebrte are roughened by irregular or granulate ridges, directed 

 toward their summit, which is bent backward.' Another agrees exactly with 

 No. 39849 British INIuseum specimen labelled Pretmosaurus rugosus, but which has 

 been shown " to be a vertebra of Plesiosaurus rostratus from the Lias of Lyme 

 Regis. 



The specific determination of this Plesiosaurus (hitherto recognised only as 

 Liassic) is a new record altogether for the Rhietic throughout the world, its verte- 

 brae having hitherto been referred geuerically only, and its teeth having been 

 recorded as Termatosaurus albertii, PlieningerJ and Plesiosawnis sp. non det. The 

 synonymy, therefore, will be as follows :— 



■ A Monograph of the Fossil Reptilia of the Liassic Formations, part iii. (Palaeon- 

 tographical Society, 1865), pp. 20-30, plates ix.-xiii. Note, however, that part of the 

 description between pp. 2G-30 refers to Plesiosaurus conybcarei [-ri] (Sollas), as does 

 the whole of the plate (skull), tab. siii. (see R. Lydekker, Catalogue of Fossil Rep- 

 tilia and Amphibia, British Museum, part ii. pp. 269, 270, and Woodward and Sher- 

 born). 



- Beitrage zur Paldontologie Wiirttemberg's (1884), p. 123, tab. xii. figs. 93, 94. 



^ Ber Jura (1858), p. 33, and atlas, tab. ii. figs. 4-8. 



* Handbuch der Petrefaktenkundc (1885) p. 212, tab. xvi. figs. 7-10. 

 ' See note above (pp. cit.). 



* Catalogue of Fossil Reptilia and Amphibia, British Museum, vol. ii. p. 273. 



