On Remains of Ichthyosaurus and Plesiosaurus in Australia, 355 



towards the north, Iceland and Greenland possessed not only- 

 pines and birches, poplars, willows, oaks, and alders, but also 

 Sequoia and Salisburice, elms, hornbeams, figs, Magnolia, Lirio- 

 dendra and vines, the analogues of which cannot now be found 

 nearer than at least 12° more towards the south : these organisms 

 required, in order to fructify and propagate, a mean temperature 

 which M. Heer estimates at not less than 9°-5 C. ( = 49°F.). 

 Even beyond the Polar circle, at Spitzbergen, about 79° N. lat., 

 the Tertiary vegetation, according to the same author, still in- 

 cluded hazels, hornbeams, and planes ; and this vegetation was 

 probably continued to the Pole itself. 



Such was Europe in the Miocene age; only at the end of this 

 period, in consequence of phenomena of which we are ignorant, 

 or perhaps by the action of several combined causes, the tem- 

 perature tended to diminish : this decrease, when once well 

 marked, continued until the glacial times, when the cold, 

 exceeding that of the present period, drove from our soil the 

 greater part of the plants which previously ornamented it, and 

 which, but for this circumstance, would have remained upon it, 

 at least in part, and would have still subsisted there — our climate, 

 in consequence of a fresh change, having subsequently been 

 tempered. 



L. — On the Occurence of Ichthyosaurus and Plesiosaurus in 

 Australia. By Frederick M'Coy, Professor of Natural 

 Science in the University of Melbourne, and Director of the 

 National Museum of Victoria. 



To the Editors of the Annals of Natural History. 

 Gentlemen, 



Referring to my paper in your Journal for November 1865, 

 on the discovery of Cretaceous fossils in Central Australia, I have 

 now the great pleasure of announcing the important fact that 

 additional specimens have been received from Messrs. Carson and 

 Sutherland, from the same locality, on the head of the Flinders 

 River, enabling me to demonstrate the existence of Enaliosaurian 

 reptiles in continental Australia during the period of Mesozoic 

 deposits, which most geologists suppose not to occur in Aus- 

 tralia. The remains are of the two well-marked genera IchthyO' 

 saurus and Plesiosaurus. Of the former there are numerous 

 vertebrse, deeply biconcave with conical articular surfaces, the 

 centrum 4 inches wide, 3 inches deep, and 1^ inch long. The 

 species I name Ichthyosaurus australis (M*Coy) . 



One of the species of Plesiosaurus has a slight resemblance 

 to the New Zealand species noticed by Professor Owen, but is 



