28 T. G. HALLE, MESOZOIC DEPOSITS AND FLORAS OF PATAGONIA AND TIERRA DEL FUEGO. 
The type-specimens of Cladophlebis Browniana DUNKE. are not very like the 
Patagonian fragments; but the name C. Browniana has been used here in accordance 
with SEWARD, who has included in this species both Pecopteris polymorpha DUNK. 
(= P. Dunkeri SCHIMP.) and P. Ungeri DUNK. Owing to the great variation of 
this kind of frond, the separation of DUNKEF'S three species certainly often meets 
with difficulty, and several specimens referred to Cladophlebis Browniana closely 
resemble both DUNKERS and SCHENK'S specimens of Pecopteris Dunkeri and also the 
Patagonian fragments. This is especially the case with some fragments figured by 
YOKOYAMA (1894; pl. 27, figs. 2—4, 5 c and d) from the »Wealden» (Ryöseki Series) 
of Japan. One of his specimens (fig. 3 a), though larger than the Patagonian frag- 
ments, shows the same kind of venation as the latter. BERRY (1911, p. 257), who 
keeps Cladophlebis Ungeri and C. Brownmiana separated, remarks in this connexion on 
the danger of unwarranted identification of similar forms. Though agreeing entirely 
with his opinion as a general principle, I have preferred, in the present case, to follow 
SEWARD in making use of the name C. Browniana for the Patagonian specimens. 
These are, as already stated, of the type of Pecopteris polymorpha DUNK.; and the 
facts that this form occupies an intermediate position between C. Browniana and C. 
Ungeri and that all these three forms often occur together in other parts of the 
world may be regarded as reasons for the broader classification. 
There are in the collection some fragments (one of which is shown in pl. 4, 
figs. 6, 7) which possibly represent pinnae of the typical Cladophlebis Browniana DUNKE. 
with entire pinnules. These pinna-fragments are small, only 2 cm. broad, at most, 
with the pinnules rather densely set. The pinnules are narrow and linear, rather 
abruptly tapered at the apex, which is only slightly acute; the edges are entire or 
a little dentate towards the apex. The insertion is by means of the whole of the 
base. The venation consists of a fairly strong midrib, persisting to the apex, and 
oblique secondary veins which, as a rule, bifurcate only once. — These fragments 
undeniably show some resemblance to typical specimens of C. Browniana, but the 
difference is too great to be in accord with an unreserved identification. The pin- 
nules of the Patagonian specimens are longer and more pointed, and not directed so 
much forward; moreover, the venation appears to be denser. 
Cladophlebis Browniana (DUNE.) SEW., taken in a wide sense as including also 
Pecopteris Dunkeri SCHIMP. (= P. polymorpha DUNK.), is distributed almost all over 
the world, in rocks ranging from the Wealden (sens. str.) to the Albian. Itisinter- 
esting to note, in relation to the present locality, that the species has recently been 
recorded by ZEILLER (1910) from the Wealden of Peru, where it occurs in a fertile 
state, having large biseriate sporangia of the type of the Schizaeaceae. 
The specimens here described under the name of Cladophlebis Browniana are 
all from locality c at Rio Fösiles. 
