18 GEOLOGICAL MEMOIRS. 
stinctly stratified, lies the Bleiberg limestone, in which lead ores are 
found. This again contains the same bivalve shell with the grey 
limestone near Hallstatt. It was distinguished by Boué as an Iso- 
cardia, and occurs here in smaller but better-preserved specimens 
than at Hallstatt. 
Below the limestone with lead ore follows red sandstone, which is 
found both north of Bleiberg in the Drauthal and also on the south- 
west in the so-called Windische Graben. Still lower is greywacke 
and greywacke-slate with numerous petrifactions, among which 
M. Lipold very recently detected Trilobites. Count Keyserling and 
M. Barrande, who lately examined these fossils when in Vienna, 
discovered among them several forms peculiar to the coal formation. 
The series of strata therefore from below upwards appears in both 
localities to be this :— 
1. Greywacke and greywacke-slate. 
2. Red sandstone. 
3. Grey stratified limestone with Isocardia. 
4, Cephalopod strata. 
Since the above work appeared F. von Hauer has published* a 
description of some additional species of Cephalopods from the red 
marble of Aussee. To the three Orthoceratites formerly described he 
now adds three new species also associated with Ammonites. This 
younger generation of that ancient family presents no general charac- 
teristic distinction from the older species, except perhaps in the greater 
width of the chambers. In three species the siphon is central, m other 
three close onthe margin. The species described are, O. reticulatum, 
O. alveolare, Quenstedt, O. convergens, with marginal siphon, and 
O. dubium, with perfectly central siphon. The Nautilus mesodicus, 
Quenstedt, he now considers as probably a mere variety of the 
N. giganteus of D’Orbigny (Terrains Jurassiques, pl. 36). To this 
he now adds N. Sauperi, N. Breunneri, N. Barrandi. The latter 
belongs to the division (V. Imperfecti of Quenstedt) with perforated 
umbilicus, of which only one, NV. excavatus, Sowerby, has hitherto 
been found in the lias; the others, according to De Koninck, bemg 
all paleeozoic. The only new Goniatite is the G. Haidingeri. Of 
Ammonites ten species are noticed, 4. Gaytani, v. Klipstein, 4. Aus- 
seeanus, A. Johannis Austria, v. Klipstein, 4. Layeri, A. Simonyi, 
A. Jarbas, A. noduloso-costatus, v. Klipstem, A. striato-falcatus, 
A. Credneri, v. Klipstein, and 4. tornatus. 
This addition to the fauna of the formation does not tend more to 
decide its age than the species already known from the viemity of 
St. Cassian, Hallstatt, Bleiberg, &c. For whilst a series of Am- 
monites with uneven margin (ringsgezacten) and two of the Nautili 
(NV. Sauperi and N. Breunneri) have in general partly the aspect of 
jurassic, partly of cretaceous species, on the other hand the new 
Orthoceratites, the WN. Barrandi and G. Haidingeri, merease the 
* In Haidinger’s Naturwissenschaftliche Abhandlungen, Bd. i. (Wien, 1847), 
p. 257-277. Compare also Ib. p. 21-30, On the Cephalopods of the Shell-marble 
of Bleiberg. 
