12 
T. G. HALLE. 
(Schwecl. Südpolar-Exp. 
Genus Cladophlebis Brongniart. 
Cladophlebis denticulata (Brgn.). 
PI. 2, figs. 7 — g; text-fig. 3. 
Pecopteris denticulata, Brongniart 1828 a, p. 57. 
Pecopteris denticulata, Brongniart 1834, p. 301; pl. 98, figs, i, 2. 
Cladophlebis denticulata, Nathorst 1876, p. 19. 
Cladophlebis, Nathorst fig. in: O. Nordenskjold, J. G. Andersson etc., 1904, p. 253. 
To this species belong a number of fine fronds, which only occasionally, how- 
ever, show the finer details. 
The fronds have been very large and stout. On the counterpart of the specimen 
shown in fig. 8, the breadth of one of the fronds is seen to have exceeded 30 cm. 
On the same large slab there are also impressions of two other fronds, all three 
parallel to each other and at equal distances, as if they had been borne by a common 
rachis or stem. This, however, would be outside the slab. The rachis of the frond 
in fig. 8 measures up to 6 mm. in breadth on the counterpart. The pinnae are 
alternate, long and slightly curved and of typical shape. The pinnules are attached 
by the whole of the base, slightly falcate, and pointed at the apex. The margin 
appears mostly to be entire; but this is probably largely due to its being slightly 
recurved. In some places, where the margin is more distinct, it is seen to be finely 
but distinctly dentate, at least in the upper parts of the pinnules. The dentation is 
not well shown in the figures given in pl. 2; only in 
fig. 9 can there be seen a faint indication thereof. Text- 
fig. 3 shows a fragment of a typical pinna with clearly 
dentate pinnules. 
The venation is of the usual Cladophlebis-type, 
but it is not very well seen in any of the specimens. 
Only the lowermost lateral veins in each pinnule divide 
Fig. 3. Cladophlebis denticulata (Brgn). "10^^ than once, and even these only occasionally. 
Portion of a pinna, “/i- The Antarctic specimens should certainly be in- 
cluded in Cladophlebis denticulata (Brgn.) whatever 
limits be assigned to that species. The specimens with clearly dentate pinnules 
show indeed an almost perfect resemblance to BrONGNIART’s type-specimens, the 
dentation being only somewhat finer and denser. 
It is generally agreed that C. denticulata is not a species in a systematic sense. 
Its distribution is therefore a matter of little importance. The type of frond is a 
very common one in the Middle and Upper Jurassic, and also some forms from the 
Wealden and even from the Lower Cretaceous are considered to be closely related 
(Seward, 1900). It is very widely distributed geographically; but I am inclined to 
