OF THE FOSSEL PLANTS OF THE COAL-MEASUBES. 
255 
structure. M. Brongniart has figured four species from St. Etienne in which the 
internal organization is preserved. The author says of this genus : — “ Sa structure 
montre line graine orthope, la chalaze correspondant a l’echancrure basilaire, et le 
micropyle a la pointe opposee; le nucelle a un sommet conique sans apparence de 
cavite pollinique. Mais ces graines presentent, dans leur testa, deux structures tres- 
difierentes, et qui pourraient engager a y distinguer deux genres. Le C. sclerotesta 
ofire un testa entierement dur et nettement limite a l’exterieur. Le C. drupctceus pre- 
sente, au contraire, un tissu tres-dense pres de sa surface interne, qui passe insensible- 
ment a un tissu a grandes cellules plus transparentes, formant une zone probablement 
charnue comme celle des graines de Gingko, et presentant meme des espaces plus trans- 
parents assez regulierement disposes ; correspondant sans doute a des cavites gommeuses 
aux oleagineuses.” 
I have found fine examples of this genus in the Oldham nodules, to which Mr. 
Butterworth has added the fine species to which I have appended his name as a 
memorial of the services he has rendered to Palaeontological Botany, by his diligence in 
collecting and making valuable sections of the Oldham plants. 
Fig. 116 represents a specimen which exhibits much of the external contour of the 
seed on the side figured, whilst on the opposite surface of the specimen I have obtained 
the somewhat oblique, longitudinal section represented in fig. 117. Occupying the 
central part of the former figure, we see a triangular nucleus with rounded angles. A 
prominent, obtuse, longitudinal ridge separates most of the surface of this nucleus into 
two triangular areas, which slope away from the ridge in each direction towards a thick, 
rounded, and very prominent margin, n', n', which surrounds the two sides and the apex 
of this nucleus. At the chalazal extremity the central longitudinal ridge dichotomizes, 
and is prolonged in each direction to the two obtuse latero-posterior angles, n", n", of the 
nucleus, thus defining a third or posterior area, i, which, though triangular, like the two 
lateral ones, is so much shorter as almost to constitute a truncate chalazal base of the entire 
nucleus. This nucleus is the thickest at the prominent point where the longitudinal 
and transverse ridges meet. Its superficial surface is thus seen to constitute a depressed 
cone, of which the apex is excentric. The maximum length of the nucleus, so far as it 
is visible in this specimen, is about Tl, and its diameter across the obtuse apex of its 
prominent conical surface is about the same. External to the nucleus we can readily 
discern, on each side of the seed, two investing membranes, an outer (a) and an inner 
one (&), which taper away together, forming a long micropylar prolongation, c. 
Unable to obtain a transparent section, I ground away the opposite side of this fine 
seed, and obtained the result seen in fig. 117, which is again enlarged 15 diameters. 
Either the section is slightly oblique or, as other specimens indicate, the seed has been 
liable to become somewhat twisted instead of being always symmetrical. It now shows 
very clearly the distinction of its various parts. At ri we have a central nucleus, of 
which some of the parenchymatous cells are preserved. These cells, as in all the species 
of Cardiocarpon in which I have found this perispermic tissue, are of large size, some of 
2 n 2 
