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UPPER BAJOCIAN
BALTIC REGION AND POLAND
The Pomeranian drift yields a full suite of Strenoceras, Garantiana,
Spiroceras, Parkinsonia and Bigotites (Stoll, 1934), indicating an extension
to the western Baltic of the full sequence in the Hanover-Brunswick
area. (Palaeogeographical treatment in Brinkmann, 1924.)
LOWER AND MIDDLE BAJOCIAN
Two small indeterminable Stephanoceratids are known from drift
at Rostock and near Berlin (Brinkmann, 1924, p. 486), but now that Bentz
has established that some Stephanoceratids range up into the Subfurcatum
Zone in NW. Germany, these cannot be regarded as proof of the extension
of the Middle Bajocian sea. The only other zone represented among the
erratics is the basal Opalinum Zone with Hudlestonia affinis (Seebach)
in an ironshot oolite. This rock is found only west of the Oder. A
Leioceras of about Opalinum Zone date has been figured from the drift
of Jutland (Skeat & Madsen, 1898, pi. i, fig. 8). Under Denmark
the 313 m. of deltaic series presumably represents largely Bajocian
sedimentation.
TOARCIAN
In the west, in Jutland, Schleswig-Holstein and Mecklenburg, glacial
drift has yielded Dactylioceras, Peronoceras (Skeat & Madsen, 1898,
pi. i, fig. 7) and Hildoceras, in addition to later zonal forms some of which
are found farther east. In the Danish borings, however, no Toarcian
ammonites appeared. In Pomerania only Upper Toarcian is found, and
of that only the zones of Harpoceras elegans and Grammoceras striatulum
are represented (Frebold, 1928, p. 122).
PLIENSBACHIAN
The Spinatum Zone is the latest Jurassic zone preserved in situ on the
isle of Bornholm. Fragments of Pleuroceras have been figured from there
(Hohne, 1933, pi. xiv) and both Pleuroceras spp. and the contemporary
Pseudoamaltheus are widespread in the drift of Denmark, Mecklenburg
and Pomerania (Frebold, 1928, p. 120). The latter has been misidentified
as Amaltheus margaritatus. A. margaritatus and Pleuroceras spinatum
and also Lower Pliensbachian ammonites were recognised in the Gassum
boring in Denmark by Frebold (in Gregersen & Sorgenfrei, 1951).
The Lower Pliensbachian was a time of marine transgression. Ammonites
of the Jamesoni and Ibex Zones occur in situ in Bornholm and
Scania, as shown by Phricodoceras bornholmiense (Hohne) and various
Acanthopleuroceras (valdani-maugenesti group) of the Ibex Zone, and
Tragophylloceras numismale (Quenst.) figured from Bornholm (Hohne,
1933, pis. xii-xiv). Ammonites of the Ibex Zone "and in addition Androgynoceras
capricornus of the Davoei Zone are widespread in the drifts of
Pomerania and Mecklenburg; and Polymorphites polymorphus (Quenst.)
of the Jamesoni Zone occurs in Denmark. In Scania the Lower
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