KUNGL. SV. VET. AKADEMIENS HANDLINGAR. BAND 51l|. N:o 3. 37 
sufficient importance to prevent the specific identification. Not only is the manner 
of insertion of the pinnae identical, but also their falcate shape and pointed apices, 
their venation and the wide angle formed with the rachis. The only difference which 
can be perceived is that the pinnae are perhaps a trifle more distant in the Pata- 
gonian specimens. This character is very vague, however, and in some of the Pata- 
gonian fronds the pinnae are about as densely imbricate as in the Indian specimens. 
The English Ptilophyllum pectinoides differs from the latter by having pinnae which 
are yet more distant than those of the Patagonian form, and which are attached at 
a more acute angle to the rachis. Furthermore, the pinnae of the English form 
taper more gradually from the base to the apex. The Patagonian specimens undoub- 
tedly come much nearer to the Indian Ptilophyllum acutifolium in these respects. At 
least as far as the typical specimens are concerned, therefore, it appears certain that 
identification with the Indian species is the right course. Regarding the specimen in 
pl. 3, fig. 11, the question is more doubtful; but, as has been set forth above, it 
seems best to refer it to the same species, too. The small fragment with shorter 
and more obtuse pinnae (pl. 3, fig. 10) approaches Ptilophyllum cutchense MORR., but 
the great variation displayed also by the Indian specimens warns us against a specific 
separation on this character only, as long as none of the more complete specimens 
show any resemblance to the other species. 
Ptilophyllum was held by FEISTMANTEL to be exclusively an Indian genus. 
Since SEwARD has stated that there is no generic difference between the Indian and 
European fronds of this type, the distribution of the genus is a matter of minor 
importance. The Indian species, however, do not appear to have any wide range of 
distribution. Ptilophyllum acutifolium has its main distribution in the Rajmahal 
Group, considered by FEISTMANTEL to be of Liassic age. It occurs also in the higher 
divisions of the Gondwana Series, even in the Kach Group, but for the greater part 
it is here substituted by P. cutchense. The species has later been recorded by ZEILLER 
(1900) from Southern China. 
In Patagonia the species was found only in locality c at Rio Fösiles. Most of 
the specimens occur in the hard slate, only those figured in pl. 3, figs. 11 and 12, 
in a coarse greyish white sandstone. 
Baiera cf. australis M' Coy. 
IPISrARAfROSEN23= 30 9EPL. 05 UpSe L- 4,07, 02 
Boera australis M'Coy 1892, in: STIRLING 1892, pl. 1, fig. 2; and: 1900, p. 5; pl. 1, fig. 3. 
» » SEWARD, 19044, p. 177; figs. 36, 37. 
The Ginkgoales are represented in the San Martin flora by a comparatively 
large number of leaves, of which at least the majority belong to one species. 
Leaf with a more or less definite petiole which is at least 1 cm. in length. 
Lamina passing gradually into the petiole, broadly cuneate, with the edges forming 
an angle at the base of from 60” to about 180”, generally about 90”. Lamina deeply 
