FAUNA. OF THE GOSAU FORMATION. 



703 



of ravines ; in the " Nene Welt 99 (south of Yienna, west of Wiener 

 Neustadt) a number of coal-mines give the opportunity of following 

 the succession of beds, although they are highly disturbed here ; and 

 I believe that the succession is not very different in the two valleys, 

 notwithstanding their distance apart. 



The base of the Gosau beds is formed by a calcareous breccia of 

 variable thickness, evidently the consolidated debris of the surround- 

 ing mountains. 



Then follows a series of freshwater beds, sandstones, marls and a 

 few seams of coal, accompanied by freshwater Mollusca such as Mela- 

 nopsis, Dejanira, Boysia, Tanalia, Cyclas, and Unio, and the remains 

 of a highly heterogeneous flora, comprising a true Palm, together 

 with Pecopteris Zippi, Microzamia, Cunninghan cites, and leaves of a 

 dicotyledonous tree resembling Magnolia, &c, evidently the ming- 

 ling of the younger dicotyledonous type with a number of survi- 

 ving older types. It is this horizon which has yielded the reptilian 

 bones. 



Deposits of a brackish character, with Cerithium, OmpTialia, and 

 Actceonella, begin to appear above the freshwater beds, sometimes 

 apparently intercalated with them and accompanied by gravel 

 beds and conglomerate, sometimes also by the first true marine 

 strata, usually characterized by Hippurites organisans and Nerincea 

 bicincta. 



The next group is formed by a loose marly limestone or a cal- 

 careous marl crammed with reef-building corals and with masses of 

 Hippurites cornu-vaccinum, Hipp, sulcatus, Gaprina Aguilloni, 

 Sphcerulites organisans, and a good number of highly ornamented 

 Gasteropoda. This is the true French Turonian zone of Hippurites 

 cornu-vaccinum. 



This zone is succeeded by a series of loose grey and marly sand- 

 stones, likewise very fossiliferous. The reef-building corals and 

 Rudistse have disappeared or are very rare, corals being represented 

 by a few species of Gyclolites, by Diploclienium lunatum and especially 

 by Trochosmilia complanata. Here the first Ammonites appear. 

 Natica bulbiformis, Cardium productum, Protocardia Hillana, 

 Trigonia limbata, and Janira quadricostata are some of the most 

 characteristic fossils. 



In some places rose-coloured limestone beds with Orbitoides and 

 the remains of a small Decapod are seen, which seem to succeed 

 directly to this zone, which I have sometimes named the zone of 

 Trochosmilia complanata. 



The last and highest member of the Gosau beds is a series of 

 sandy loose sandstone beds, containing no fossil except great 

 numbers of Inoceramus Grispii. 



I cannot, therefore, say positively that the age of the reptiles 

 which you have had the kindness to study is quite exactly that of 

 your Cambridge phosphate-beds ; but it is certain that they are older 

 than the true Turonian deposits, and especially older than the zone 

 of Hippurites cornu-vaccinum. 



