276 COSMOS. 



manifested in vertebrated animals. The most ancient of 

 these, as we have already seen, are fishes; next in the order 

 of succession of formation, passing from the lower to the 

 upper, come reptiles and mammalia. The first reptile (a 

 Saurian, the Monitor of Cuvier), which excited the attention 

 of Leibnitz,* is found in cuperiferous schist of the Zechstein 

 of Thuringia; the Palceosaurus and Thecodontosaurus of Bris- 

 tol are, according to Murchison, of the same age. The 

 Saurians are found in large numbers in the muschelkalk.f in 

 the keupcr, and in the oolitic formations, where they are 

 the most numerous. At the period of these formations 

 there existed Plesiosauri, having long swan-like necks con- 

 sisting of thirty vertebrae ; Megalosauri, monsters resembling 

 the crocodile, forty-five feet in length, and having feet 

 whose bones were like those of terrestrial mammalia, eight 

 species of large-eyed Ichthyosauri, the Geosaurus or Lacerta 

 gigantea of Sommering, and finally, seven remarkable species 

 of Pterodactyles,^ or Saurians furnished with membranous 

 wings. In the chalk the number of the crocodilial Saurians 

 diminishes, although this epoch is characterised by the so- 

 called Crocodile of Maestricht, (the Mososaurus of Conybeare), 

 and the colossal, probably graminivorous Iguanodoii. Cuvier 

 has found animals belonging to the existing families of the 

 crocodile in the tertiary formation, and Scheuchzer's antedi- 

 luvian man (homo diluvii testis), a large salamander allied 

 to the Axolotl, which I brought with me from the large 



* A Protosaurus, according to Hermann von Meyer. The rib of a 

 Saurian asserted to have been found in the mountain limestone (car- 

 bonate of lime) of Northumberland (Herm. von Meyer, Palceologica^ 

 s. 299), is regarded by Lyell (Geology, 1832, vol. i. p. 148) as very 

 doubtful. The discoverer himself referred it to the alluvial strata which 

 cover the mountain limestone. 



*t* F. von Alberti, Monographic des Bunten Sandsteins, Muschelkalks 

 und Keupers, 1834, s. 119 und 314. 



J See Hermann von Meyer's ingenious considerations regarding the 

 organization of the flying Saurians, in his Palaeologica, s. 228-252. In 

 the fossil specimen of the Pterodactylus crassirostris, which, as well as the 

 longer known P. longirostris (Ornithocephalus of Sommering), was 

 found at Solenhofen, in the lithographic slate of the upper Jura forma- 

 tion, Professor Goldfuss has even discovered traces of the membranous 

 wing, " with the impressions of curling tufts of hair, in some places a 

 full inch in length." 



