EUROPEAN CORRELATIVES. 899 



some cephalopoda ; Arcestes is abundant, and a species of Ha lorites ap- 

 pears. There is also the remarkable Rhabdoceras, a straight species of 

 the Triassic ceratitinse representing Bactrites among Devonian goniatitina^ 

 and Baculites among Jurassic and Cretaceous ammonitinse. There is 

 also one of the two primitive forms of belemnoids, Atractites, which is, 

 however, represented by two fragments, each exhibiting the phragmocone 

 and part of the guard. 



All of these specie-, from Monotis to the cephalopoda, are forms more 

 or less characteristic of the younger Trias, and if found in Europe would 

 unhesitatingly lie considered as belonging to the Noric series. After 

 having expressed this as a provisional opinion in public, I found that 

 Mojsisovics, who has done more than any one else to establish the sub- 

 divisions of the Trias on a sound basis, had already published the same 

 opinion in considering the fossils described by Gabb in the paleontology 

 of California.* 



Halobia Bed. — Above the Rhabdoceras limestone lie unfossiliferous 

 quartzites, but to the westward, near the top of the Carboniferous spur 

 (so called on account of the presence of fossiliferous rocks of that system), 

 we found a bed of slates containing Halobia occurring in banks as did 

 the Monotis below on the Triassic spur. 



These shells have the large anterior ear as in Halobia rugosa, a charac- 

 teristic species of the upper Noric and lower Karnic series in the Alps, 

 according to Mojsisovics, and there are some forms approximating to 

 Halobia superba of the Karnic. The incoming of Halobia after Daonella, 

 which occurs only in the upper part of the Mound* bed, suggests that we 

 have here a fragmentary but parallel history to that in the Alpine Trias 

 so thoroughly worked out by Mojsisovics. Thus, the Monotis and Rhab- 

 doceras beds will probably prove to be characteristic fragments of the 

 Noric series, while the Halobia slates and Hosselkus limestone of Diller 

 may prove to be passage beds from the Noric to the Karnic series. These 

 slates contain calcareous portions, and in a, small mass of this kind a 

 fragmenl of a species of Tropites occurred which was sufficiently well 

 preserved to show the very peculiar form and similar markings to those 

 of the well known lower Karnic species, Tropites subbidlatm. This was 

 accompanied by an Arcestes and fragments of Atractites identical with the 

 species occurring above in the Hosselkus limestone. It is possible thai 

 the calcareous slates and their fossils occurred immediately below the 

 Hosselkus limestone, hut of this there are at present no positive proofs. 

 Hosselkus Lhnest mc — -Tic Hosselkus limestone occurs above the Halobia 

 slates on Carboniferous spur, and contains the same forms oi Atractites 



i eber Pelecypoden Gatt. Daon tin u, Halobia: Abh. d. k. \t. geol. Beiehsivnst., 1'.. mi. 1874,8 \. 



