KUNGL. SV. VET. AKADEMIENS HANDLINGAR. BAND 51. N:0 3. 31 
than in the form referred by SEWARD (1894, pl. 6, fig. 1) to the same species under 
the name Ruffordia Goepperti var. latifolia. 
It remains to consider another specimen of which the attribution to this species 
is uncertain, though it is no doubt best described here. The pinnules of this speci- 
men, which is shown in pl. 2, fig. 8, are broad, ovate—cuneate, and are split up 
into more or less confluent cuneate lobes. Each lobe contains a few veins, and is 
dentate at the apex, with one vein passing to each tooth. The rachis is flexuous 
and winged with decurrent pinnules, the lamina appears to have been thin and filmy. — 
This form is apparently very different from the typical ones described above. The 
difference, however, lies only in the lesser degree of dissection of the frond: if the 
pinnules were split up deeper, so that the veins now seen came to run each through 
one narrow segment, the frond would become very like the typical specimens of the 
species. Among the specimens described by other authors, one from the English 
Wealden figured by SEWARD (1894; pl. 5, fig. 3 B) may especially be mentioned, 
though even that specimen is considerably more dissected. Another specimen to 
which there is a yet more striking resemblance, is one recently figured by BERRY 
(1911, pl. 24, fig. 7) as Achrostichopteris longipennis FONT. from the Potomac of 
Virginia. The shape and the venation of the ultimate segments, and also their apical 
dentation, agree closely with the corresponding characters in our frond. Other speci- 
mens referred by BERRY (l. c.) and FONTAINE (1889) to Åchrostichopteris longipennis 
are rather different; and it is not certain that the specimen mentioned should be 
ineluded in the same species. There is also some difference between the frond figured 
by BERRY and our specimen, the pinnules of the former being dissected in a more 
palmate manner. 
Sphenopteris (Ruffordia?) Goepperti has a wide distribution in Wealden rocks 
in the Northern Hemisphere, having been recorded both from Europe, from North 
America and Eastern Asia. It is found also in Middle Jurassic rocks in England 
and possibly in North America. In the Southern Hemisphere it occurs in the Middle 
Jurassic flora of Graham Land. 
All the specimens are from locality c at Rio Fösiles. 
Sphenopteris cf. naktongensis YABE. 
PIE ANT: 
Cf. Sphenopteris naktongensis YABE 1905, p. 38; pl. 4, figs. 10, 11. 
To the little known species Sphenopteris naktongensis have been doubtfully 
referred a couple of specimens which do not afford a sufficient material to permit of 
a definite determination. 
The largest fragment is the one shown in pl. 4, fig. 9. It consists of a rather 
stout rachis and portions of some pinnae which appear to have an opposite arrange- 
ment. The pinnae are more or less deeply dissected into pinnules which have a 
cuneate base; and some of which seem to be somewhat irregularly lobed. The vena- 
