ON SOME ME SO ZOIC FOSSILS. 3 
a frond bearing strap-shaped pinnules which, set at right angles 
to the rachis, are decurrent, separate, alternate, attached to the 
rachis by the whole base, and have veins parallel to each other and 
to the margins of the pinnules ; furthermore by its appearance among 
Mesozoic fossils. 
Spec. Char. — Pinnules long, four times as long as broad, 
apices mucronate by truncation in an upwardly curved direction, 
pointed ; bases slightly contracted ; veins 10 to 12 in number ; 
rachis narrow, not striated, the part in sight not attenuated. 
The veining is preserved on the bases of several of the lower 
pinnules, but in a condition which renders it somewhat difficult to 
ascertain their number precisely. I cannot, however, count more 
than twelve. 
It is generally understood that the Pterophylla became extinct 
in the Jurassic period. The only hint to the contrary that I can 
find in literature available to me is the P. ernestina, Stieht, and the 
right to a place in the genus claimed for this plant is, according to 
Schimper, dubious. The rock on which the pinna is displayed is 
in all respects identical with the matrix of the fossils accompanying 
it. If the foliage and the stem belong to the same species, as 
indeed seems more than probable, this Cretaceous Pterophyllum 
fails to show that the genus was even then represented by a 
decadent species. 
The righteous protest uttered by Professor Porbes, in his 
Presidential Address to the Geological Society in 1854, against 
" rolling in the catalogue of new types morsels " of plants 
should be borne in mind whenever the temptation to do so is felt. 
But in the present instance the identity of the genus is so 
obvious, the specific novelty rendered so probable by the extreme 
rarity, if not absolute want, of previous discovery of Pterophyllum 
in the Cretaceous flora, that I feel justified in proposing for the 
plant a distinctive name. 
NOTOCHELONE COSTATA, Owen. 
PI. iii, tig 1 ; PI. iv. 
Thirty years have nearly elapsed since Sir Richard (then Mr.) 
Owen described, under the name JVotochelys # costata, part of the 
carapace and plastron of an extinct Australian Chelonian. Since 
the date of that description, 1882, nothing more, so far as I am 
* Subsequently changed to Notochclone by Mr. Lyddeker. 
