British Coal Measures . 89 
chamber could be seen, and there is thus no doubt as to the seed nature of 
this fossil. 
Cornucarpum acutum (L. and H.) is easily distinguished by the more 
or less triangular shape and the broad apex, with a fairly long horn at each 
corner. There is also a median ridge. It is thus quite distinct from 
Cardiocarpus as here defined. 
Cardiocarpus , Brongn. 
This name was first instituted by Brongniart 1 in 1828 for seeds with 
the following characters: ‘fruits comprimes, lenticulaires, cordiformes ou 
reniformes, terminds par une pointe peu aigue.’ In recent years there has 
been some difference of opinion as to whether this genus should be made to 
include winged seeds. Brongniart’s diagnosis says nothing about wings. 
I am inclined to reserve it for those seeds which apparently did not possess 
a broad sarcotesta, but in which the testa was heart-shaped or reniform. 
The following are the British species : Cardiocarpus congruens , 2 Grand’ Eury 
(Text-fig. 3, p. 97), and C. Gutbieri , Gein. (PL VI, Fig. 15). The species 
referred to this genus by Artis as C. marginatus (PI. VIII, Fig. 46) is still 
a type of very uncertain affinities. It may be a radiospermic seed. It 
must also be remembered that the nucule of badly preserved Samaropsis 
seeds, in which the wing is not preserved, may simulate Cardiocarpus . In 
some species of Cardiocarpus there appears to be a slight rim or wing, but 
I am inclined to think that this is wholly due to the effects of pressure. 
Samaropsis, Goepp. 
The genus Samaropsis , Goepp., is maintained here as used by con- 
tinental authorities in more recent years, though in a slightly restricted 
sense. In these seeds there is a distinct nucule in the centre, surrounded 
by a broad rim called the wing. The nucule is heart-shaped or oval, and 
the whole wing circular, or oval, or heart-shaped. I would restrict this 
genus to seeds which are not much longer than broad, or broader than long, 
separating those forms with a very long and narrow wing as a distinct genus 
Samar ospermum . Samaropsis differs from Cardiocarpus in the clear dis- 
tinction between the nucule and the wing. In other words, in Samaropsis 
there is a well-developed sarcotesta; little, if any, in Cardiocarpus . The 
nucule is of course the sclerotesta. 
I propose to refer all Platysperms, with a triangular or heart-shaped 
nucule, surrounded by a more or less circular wing, to Goeppert’s genus 
Samaropsis , founded in 1864. The British species of Samaropsis are 
Jluitans , Dawson (PI. VI, P"ig. 18), S. crassa , Lesq. (Text-fig. 4), S* 
1 Brongniart (’28), p. 87. 
2 This may be the Carpolites corculum or C. contractus of Sternberg (Vers. Darstell. Flora 
d. Vorwelt, Heft 5-6, p. xl, Heft 1, PI. VII, Figs. 6 and 7, 1820-33), but Sternberg’s figures appear 
to be too indefinite to permit of any certain correlation. 
