34 T. G. HALLE, MESOZOIC DEPOSITS AND FLORAS OF PATAGONIA AND TIERRA DEL FUEGO. 
explicitly stated to be derived from the Jurassic rocks of Solnhofen, one might be 
tempted to regard it as a leaf of a dicotyledon. The venation of the specimen is 
most indistinct; but, in as far as it admits of forming any opinion, it would seem 
to be quite different from that of the present specimens, indeed, more suggestive of 
a dicotyledon. There can hardly be any auestion, under such circumstances, of re- 
ferring the Patagonian form to this very problematic genus. 
Another genus which may be considered in this connection is Stormbergia 
(SEWARD 1911a) from the Stormberg Group of South Africa. The pinnules of this 
plant have rounded bases, short petioles and a venation of the Cladophlebis-type. 
The habit of the bipinnate frond, with its short pinnules, is very peculiar, and the 
venation differs from that of our specimens in consisting of only few and distant 
secondary veins in each pinnule. 
In the absence of any other form-genus to which the present specimens could 
be referred, I had considered the possibility of describing them under the name of 
Stormbergia, using this genus in a wide sense, for fern-leaves having stalked pinnules 
with rounded bases. Professor ZEILLER, who has kindly examined drawings of the 
specimens, has pointed out, however, that, considering the peculiar characters of the 
only species known of Stormbergia, it would be better to employ the name Asplenites, 
as a provisional designation. 'The reasons for choosing this name would be the fact 
that among recent ferns a similar shape of the pinnules is found chiefly in the genus 
Asplenium, and that it would be possible, in this manner, to evade the undesirable 
creation of a new generic name. In adopting this course, it must be stated that 
the present form belongs to quite another type than those for which GOEPPERT (1841 
—1846, p. 111) created his genus Asplenites, which is no longer used in its original 
sense, and that the name is employed here quite provisionally in want of a better one. 
The species was found only in locality c, at Rio Fösiles. 
Ptilophyllum acutifolium MOoRrRis. 
IPlSnos 12 
Ptilophyllum acutifolium Morris 1837, p. 327; explanation of pl. 21, figs. 1 a, 2, 3. 
il 
Palaeozamia > OrDHAM & Morris 1863. p. 29; pl. 20; pl. 21, fig. 2. 
Ptilophyllwm » FFEISTMANTEL 1876, p445 pl 5yfg: 4 LS87T7) pr II spsR2NpPir ne 
1877 a, Pp: 655 pl. 40. — 1877 b, Pp. 16; pl2, — L84NCe, Pa JE pl DERA ös BETS NOREDAR oc DLEELON 
fos: 13, 1—95 pl ne fpLYSSNieSsA 2 ease RS 
One of the most characteristic members of the Rio Fösiles flora is a cycado- 
phyte which must be brought to the genus Ptilophyllum, that genus being taken in 
the restricted sense of FEISTMANTEL (1876, p. 5) and ZEILLER (1903, p. 171). The 
Patagonian form can with confidence be identified with Pitilophyllum acutifolium 
MORRIS. 
The species is one of the commonest fossils in locality c, and the preservation 
is fairly good. The specimens display a great variation in habit, but it is probable 
that they all belong to the same species. | 
