Bd. III: 14) 
THE MESOZOIC FLORA. 
63 
Only at the very point of insertion the edge bends sharply inwards. As a con- 
sequence of this, and of the great development of the distal basal lobe, the veins 
radiate from somewhere rather near the point in which the proximal edge of the 
pinna joins the rachis. 
In addition to the specimens described, which are here regarded as typical, 
there are a number of others of the kind shown in pi. 7, figs. 8, 9 and ii. These 
are much smaller and narrower, and have shorter and broader pinnae with the basal 
auriculate lobe much less developed. The pinnae are more crowded, and form a 
narrower angle with the rachis. The venation is about the same in both cases. The 
most important character of the more typical specimens, viz. the straight course of 
the proximal pinna-edge in its lower part, is present in some of these smaller speci- 
mens. too; in others it is more or less modified, the edge being convex also in its 
lower part. There are forms of transition between both types of fronds, however, 
and since it is probable that the small specimens such as those in figs. 8, 9 and 1 1 
represent young fronds or apical portions of larger ones, it seems permissible to re- 
fer them to the same species of which the large specimens in pi. 7, figs, i — 4, and 
in text-fig. 15 are regarded as types. 
This species comes nearest to a group of forms, ranging from the Rhætic to 
the Oolite, of which the nomenclature is in a very confused state, a number of 
names such as O. Bechci, 0 . Bucklandi, O. obtusus, 0 . brevifolius etc. being em- 
ployed differently by different authors. Of all figured specimens brought into this 
group, some of those referred by ScHENK (1867) to Ot opter is (Otorsai/iites) Buck- 
landi come nearest to our species. This is especially the case with the specimens 
in Schenk’s pi. 34, figs. 3, 4 and 6. These show a great resemblance to the Ant- 
arctic fronds both in regard to the habit and the shape of the pinnæ. The fronds 
of the present species are, perhaps, to judge from the specimen in text-fig. 15. a 
little longer and more linear, but otherwise the habit is very much the same. It 
appears, however, as if the Antarctic fronds differed through more developed anterior 
basal lobes and through the upper more linear part of the lamina being better 
marked off from the latter. The chief difference, however, is that the lower part 
of the proximal edge of the pinnæ is straighter in the Antarctic species and not 
rounded off to form a lobe. If the difference in age is added the best course will 
no doubt be to keep both forms separated specifically. Of all other forms referred 
to the same group or species as Schenk’s Otopteris Bucklandi, ^ there are none 
It is not intended to discuss here the confused nomenclature of this group of fronds, the suli ect 
having been fully treated by Seward (.1900, p. 218: 1904, p. 39) and recently by Zeiller (1912, p. 6), 
It seems to be evident that the species should not be named 0 . Bucklandi. Schenk and most other 
authors identify the Franconian form, which was first described by Fn. Br.vun (1843, P- pl- t 3 - 
13, 14) as Zamites brevifolius, with O. obtusus (Lindl. & Hutt.) (1834, pl. 128). The latter name 
should therefore be employed, if the form cannot be shown to be identical with either of Brongniart's 
