KUNGL. SV. VET. AKADEMIENS HANDLINGAR. BAND 51. N:o 3. 49 
botanical relations of the Upper Jurassic and the Lower Cretaceous. It must be 
mentioned, finally, that the genus Årithrotaxites, of which the new species A. Ungeri 
is described above, has been recorded at present only from the Upper Jurassic, but 
as only one certain cone-bearing specimen has hitherto been known, there is not suf- 
ficient evidence as to the range of the type. 
The Jurassic elements now discussed are in striking contrast to the evidence 
afforded both by the marine fossils and by the rest of the plants; but, all things 
considered, they are hardly of sufficient importance to overthrow the idea of a 
Lower Cretaceous age of the flora. 
It remains to consider the plants found at the other localities. At b were found 
only Podozamites? sp. and Gleichenites San-Martim n. sp. These are of no import- 
ance for the matter of correlation, but the latter appears to find its nearest allies in 
the supposed Urgonian flora of Greenland. TIt agrees thus far with the assumption 
that it represents about the same horizon as the flora at c, which is also probable 
from its occurrence in the lower part of division 6. 
The few plants found in the upper part of the Rio Fösiles valley, viz. Spheno- 
pteris (Onychiopsis?) psilotoides (= Onychiopsis Mantelli of most authors), S. cf. nakton- 
gensis and Dicotyledonous fragments(?), must, on stratigraphical grounds, be somewhat 
younger than the flora at ce — how much it is impossible to decide. A younger age 
may also seem to be indicated by the presence of the supposed dicotyledonous frag- 
ments, which, however, are not to be relied on. dSphenopteris naktongensis is only 
known from supposed Wealden rocks of Korea, but S. pstiulotoides is of greater im- 
portance. This species has been considered as a leading fossil of the Wealden. There 
applies to it, however, the same remark as has already been made in regard to the 
whole Wealden flora, viz. that it extends to much higher horizons than that of the 
European Wealden, sensu stricto. Not only is the species known from the Albian of 
Portugal, but it has even been recorded by ENGELHARDT (1891) from the Cenomanian 
of Niederschöna, though a confirmation in the shape of illustrations is yet wanting. 
Moreover, one of the specimens figured by VELENOVSKY (1888, pl. 1, fig. 7) from the 
Cenomanian of Bohemia may possibly be identical with this species. The range of the 
species thus extends to the Albian and possibly to the Cenomanian. TItis not neces- 
sary to suppose that the plants at this locality need be still younger in respect to 
the flora at c than is in accord with these facts: they may quite well be Albian or 
Cenomanian. The occurrence of the typical Wealden species Sphenopteris psilotoides 
on a horizon higher than that of the flora at c, which would be, according to the 
marine fossils, of Aptian age, has led Prof. SToOLLEY (1912, p. 6) to express some 
doubt as to the correctness of the statements concerning the occurrence of these 
fossils. Having regard to the facts that the Wealden flora extends all through 
the Lower Cretaceous, and that, moreover, the discord between the evidence of 
the fauna and the flora is not confined to this single case but is a difficulty experi- 
enced in other regions on this horizon, this explanation may be admitted to be un- 
necessary. 
EK. Sv. Vet. Akad. Handl. Band 51. N:o 3. 
3 
