304 L. F. Spath—Ammonites from Spitsbergen. 
One slab from the “* Nodule bed”’ of the Trident, Sassendal, full 
of Posidonomya mimer, and containing, in addition to Arctoceras, 
a fragment of one of the species of the gen. nov. (Danubites %), also 
includes a portion of what Dr. A. Smith Woodward considers to be 
Belonorhynchus wimani A. Smith Woodward. The writer, at first, 
thought that these plentiful Danubites ? might be what Wiman ? 
calls the commonest Ceratite of the “ fish-bed”’. Other fish-remains 
in the British Museum (Acrolepis), and some Ccelacanthid remains 
associated with Arctoceras and Posidonomya mamer, also are 
preserved in the black limestone that must have come from nodules 
in the Posidonomya shales. But only a few isolated specimens of 
Danubites * are found associated with Arctoceras and Posidonomya, 
whereas the nodules in which these Danubites ? occur in clusters 
are crowded with a very convex Pseudomonotis. This also 
characterises the matrix of Anasibirites and Keyserlingites, but it 
does not seem to be found in the slabs with Posidonomya mimer, 
where a less convex and smoother form (still of the P. boreas type) 
rarely occurs. 
Professor Wiman ° recorded his Labyrinthodont remains from the 
lower part of the Posidonomya shales of Mt. Marmier, and thought 
that the “fish-bed’’, not quite at the base of the Trias, might 
not represent the exact horizon from which Mojsisovics’ Arctoceras 
fauna was obtained.4 From the evidence of the specimens labelled 
“Lower Nodule Bed’’, and from Professor Gregory’s section I, 
it would appear as though both the typical Arctoceras fauna, recorded 
by Mojsisovics, corresponding with the “ Posidonomya nodules ”’ 
aforementioned, and the Anasibirites— Keyserlingites — Prionites— 
Gomodiscus assemblage, recorded here from the “ Pseudomonotis 
nodules’, occurred at about the base of the ‘* Posidonomya 
shales”. The fish-bed of Professor Wiman ® also may be near 
this horizon, C,. 
Whether the whole of the 600 feet of “ Posidonomya shales” 
above this horizon belong to the Lower Trias is doubtful. The 
“Lower Saurian horizon’ of Professor Wiman, 300 feet above the 
fish-bed, may coincide with the bed from which ? Gyronites aplanatus 
and ? Danubites strong: have been recorded, those species being 
known to occur in the “‘ Meekoceras’’ beds of Idaho and California. 
Hyatt & Smith © record Anasibirites from the same beds, so that 
1 “Notes on some Fish-remains from the Lower Trias of Spitsbergen ”’ : 
Bull. Geol. Inst. Univ. Upsala, vol. xi, 1912. 
2 “ Tehthyosaurier a. d. Trias Spitzbergens ’’ : Bull. Geol. Inst. Univ. Upsala, 
vol. x, 1910-11, Nos. 19 and 20, p. 127. ; 
3 Loc. cit., 1910, p. 34. 
4) Loe. eit.; 191 15\p. 127. 
Peliby ap l2G: 
§ Loc. cit., 1905, p. 49. In 1914 (The Middle Triassic Marine Invertebr. 
Faunas of North America, p. 4: Correlation Table) Professor Perrin-Smith 
put the Spitsbergen Posidonomya “‘ Limestones’’ as equivalent to the Meekoceras 
Beds of the Himalayas and the Proptychites Beds of the Ussuri, that is to say, 
