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inodiiied as compared with the oi’dinary sterile t'oi-m (W h i t e 1904). And still more
recently, in April of this year, M. Gr a n d ' E ury has added yet another to his many
brilliant discoveries, by describing the most striking instance of a “seed-bearing Fern"
yet l)ronght to light (Gr a n d ' F u r y 1905). This last discovery comes width a certain
shock to the minds of consei'vative palaeobotanists, for the new seed-bearing species
is Pecoj i tei ' is Pl u c ke n e t i . and we have hitherto regarded the genus Pe copt e r i s
as the most secure sanctuary ot the true Ferns. It is, however, fair to mention
that tins species is not a typical Pecopt er i s , but has been placed in various genera,
as for e.\am])le, in Dic k s o n i i t e s by S t e r ,z e l , so toi' the present the genuine
Mai’attiaceoiis Pecopterids may I'emain imdisturhed in their established position.
The fertile fronds of Pecop t e r i s
Pl u ck en e t i are hut little modilied as com-
jiared with the ordinai'v vegetative foliage,
and different paids of the same frond may
l)e fertile or sterile; in the seed-bearing
region the lamina is merely somewhat reduced.
The seeds, which are present in
hundreds on tlie fronds, are inserted at
Fig. i().
Kig. 17.
I'ig. 16. I v á genos toma S in c l a i r i . I’ortioii of I)ranclied racliis I>eariiig a nuiiiber of
cnpulate seeds. Nat. size.
, . , A Two seeds on I)ranelies of tlie racIiis; in each tiie cuinile enclosing tlie actual
seed 18 clearl)® seen, x 5.
l ig. 16 and 17. I'roni Arl)er 1905, after drawings by Miss W o o d w a r d .
the ends of lateral veins of the pinnnles; they are of small size, about 5 mm in length,
and in the mature condition are distinctly winged, closely resembling the Cordaitean
seed Sama r o ps i s , referred to the genus Do r yco r d a i t e s . It is interesting to
remember that the seeds of Mr. W h i t e s Ane imi t e s are also winged. It thus
appears that from the form alone it is not always possible to distinguish between the
seeds of the Cycadofilices and those of the wellknown and typically Gymnospermoiis
family Cordaiteae. AVhen the first seeds of the Fern-like Spermophyta were discovered,
we were apt to assume that the radially symmetrical form of seed was
characteristic of this group, while the fiat bilateral seeds were still assigned to the
Cordaiteae. In the present state of our knowledge we can no longer rely on the
validity of this distinction, and only the direct evidence of continuity will suffice to
determine to which group a given seed belonged.
I have so far made use of the name Cycadofilices for the Fern-like Seedplants,
as this name lias been familiar to botanists since its introduction by Prof.
P o t o n ié in 1897 ( P o t o n ié 1897). The group Cycadofilices, however, ivas founded
on vegetative characters, and a name is needed to indicate those Cycadofilices which
■are known to have definitely entered the ranks of Spermophyta. Prof. O l iv e r and
I have therefore iirojiosed to etablish a class Pteridospermeae for the iilants in
(piestion ( O l i v e r and S c o t t 1904); this name has been adopted by some other palaeobotanists,
and I shall employ it in my further remarks.
At present we may safely include under the Pteridospermeae, the Lyginodendreae
(witli)the foliage, so far as we know, of Spheno] ) ter is) and the Medulloseae or Neurop-
terideae. There are furtlier the types rejiresented by Aneim i t e s f e r t i l i s and
Pe co p t e r i s Plu c k e n e t i , which appear to be quite distinct from the other two
families, though in the absence of any knowledge of their structure, we cannot assign
them a more definite systematic position.
Our acquaintance with the structure of the seed in Pteridospermeae is not
yet wide enough to enable us to give a strict definition of the group; as a provisional
description we may characterize tliem as plants with the habit and with certain of
the anatomical characters of Ferns, hearing on fronds only sliglitly differentiated from
the vegetative foliage, seeds of a Cycadean type of structure. The anatomical features
of those members of the group in which the structure is known appear amply
sufficient to establish a real affinity with the Fern-phylnm, while the seeds, as at
jiresent investigated, are highly organized, and have already left far behind the
charactei's of the cryptogainic megasporangia from which we must suppose them to
have been derived. AVe shall be in a much better position to estimate the nearness
of the relation between Pteridospermeae and true Ferns when we are better acquainted
with the male organs —, the microspoi-angia or ])ollen-sacs — of the former gi'oiip. As
yet the evidence on this important point has been extremely scanty. A paper,
however, just presented to the Royal Society of London by my friend Mr. K id s t o n ,
to which he kindly allows me to refer, appeal's to clear iqi the question as regards one
important member of the group (K id s t o n 1905). Mr. K id s t o n has discovered in organic
connection with the characteristic fronds of Sphe no p t e r i s I l o n i nghaus i ( = Lygi no d
e n d ro n Oldhamium) , fertile pinnae of the type of Cr o ssot h eca, Z e i l l e r . The
ultimate fertile iiinnules bear on their lower surfaces a group of elongated sporangia,
convergent when young, but separating more widely at maturity. Tliat these bodies are
really sporangia, a point which had been somewhat disinited, is clearly proved by
Mr. K i d s t o n , who has been able to isolate the spores contained in their cavities.
Thus the nature of the male fructification of Lyg i nodend r on is settled, though we
shall await with great interest further information as to the strnctni'e of the microsporangia,
and their possible relation to the petrified synangia jireviously described
by Miss B e n s o n under the name of Telangium, and provisionally attributed to
Lyg i nodend r on (B e n s o n 1904).