KUNGL. SV. VET. AKADEMIENS HANDLINGAR. BAND 5Å. N:o 7. 7 
to this very species, as the other representatives of the genus have always been re- 
garded as being only bipinnate, which they apparently are. As for the species in 
question, there are two opinions, one being that the frond is tripinnate, and the 
other that it is only bipinnate. 'The former opinion was first pronounced by GÖP- 
PERT (1845 a, p. 144), and was later on taken up and cleared up by NATHORST 
(1878, p. 30), while the latter, which some years ago was adopted by GOTHAN (1909, 
No. 109), derives its origin from SCHENK (1867, p. 53). What GÖPPERT and NATHORST 
regarded as pinnules are, according to those authors, only fortuitous lobes formed 
by a "”nachträgliches Einreisen der Spreite", which was supported by the dentation 
of the margin. GOTHAN considers further that those scores followed the course of 
the lateral veins. 
Now we can take it for a fact that the pinnules stand very close and are 
never entirely free, and that only the very biggest specimens are characterized by 
a tripinnate segmentation (pl. 1, figs. 2, 5; pl. 2, fig. 9), while the great majority 
takes up an intermediate position between bi- and tripinnate. It is accordingly 
evident, and it appears also from their drawings, that ScHENK and GOTHAN have 
only had to do with fronds not yet fully developed. GOTHAN's opinion, however, is 
for two reasons somewhat strange, the first being that the veins would not run out 
into the teeth but exactly between them, and the second that the cuticle in this so 
xerophilous plant would be extremely thin above the veins. 
As for the venation, neither GÖPPERT nor NATHORST could come to a definite 
conclusion, though each thought he had discerned a midrib in each pinnule. Accord- 
ing to ScHENK and GOTHAN, however, it is alethopteridic with a more or less distinct 
midrib and with generally indistinct secondary veins, which according to the former 
are dichotomical, and according to the latter always simple. That which GOoTHAN 
says of the "Einreisen der Spreite” along the veins, however, proves that what he 
has understood to be veins are not such. 
Nor have I myself been able to discern any trace of venation in unmacerated 
fronds, but an examination of macerated ones may show that it is alethopteridic. 
In most specimens it is possible to distinguish a certain differentiation in the 
shape of the epidermal cells on the lower side, these being somewhat oblong in 
narrow strips in the middle of the pinnules indicating the course of midribs. 
The distribution of the stomata, however, will show the nature of the venation 
more exactly. As already mentioned, there is no difference between the upper 
and the lower epidermis save the stomata on one side, probably the upper one, not 
being equally distributed over the whole surface but more numerous in compara- 
tively narrow strips. In a large pinnule, i. e. a pinnule which will soon undergo a 
further segmentation, those strips occur rg above the future rachis, partly above 
the middle of each future pinnule (pl. 2, fig. 1). That the bands in question lie 
above and mark the veins, is fully evident fisa their occurrence. Whether the second- 
ary veins in their turn already send out lateral veins, cannot be decided, but, of 
course, they will do so sooner or later. 
There is another species, Lepidopteris stuttgardiensis (JAEG.) SCHIMP., in which 
