xxxi] 



SAMABOPSIS 



171 



of exceptionally well-preserved seeds from Midlothian: the 

 seeds of this species vary considerably in size and form; some 

 are almost orbicular and show no distinction between nucule and 

 border (fig. 444, A) while in others (B) the impression of the 

 flattened and longitudinally striated sarcotesta is clearly distin- 

 guished. Kidston is of opinion that in younger seeds there is 

 a single apical point replaced in a later stage of development by 

 two cusps, as seen in figs. A and B, formed by the opening of the 

 micropylar tube. A ridge in the middle of the flattened surface 

 indicates the position of the vascular bundles in the principal 

 plane as in Cardiocarpics. The fully developed seeds are 8 — 9 mm. 

 long. The correlation of the seeds represented in figs. 443 and 

 444 with Eremopteris fronds furnishes an additional illustration 



Fia. 444. Samaropsis acuta. (From drawings by Dr Kidston of 

 specimens in his collection, 3475 (A), 3316 (B); x 2.) 



of the impossibility of trusting to external form as a criterion of 

 affinity, for it is known that seeds of the Samaropsis type were 

 produced by Pteridosperms with foliage represented by Eremopteris 

 artemisaefolia and Pecopteris PlucJceneti, also by some members 

 of the Cordaitales (e.g. fig. 480). Dr Arber^ has recently proposed 

 a new generic name Cornucarpus for Cardiocarpon acutum, but 

 the drawings that he gives of seeds from the Kent coal-field 

 referred to this species suggest a type distinct from that of Lindley 

 and Hutton. In the absence of specimens showing actual attach- 

 ment it is impossible to say how the seeds were borne, but the 

 analogy of Wardia fertilis and Pecopteris Pluckeneti lends support 

 to the view that the seeds were attached to pinnules with a 

 reduced lamina. Eremopteris artemisaefolia occurs in the Lower 

 and Middle Coal Measures of England: a species recorded by 



1 Arber, E. A. N. (14) p. 97; (09) p. 29, PL i. fig. 5. 



