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NOTES ON TRIGONOCARPUS , BRONGN. AND POLYLO- 
PHOSPERMUM, BRONGN., TWO GENERA OF 
PALAEOZOIC SEEDS. 
By F. W. Oliver. 
I N a recent paper in the Transactions of the Linnean Society, 
dealing with the results of a re-investigation of Brongniart’s 
genus of fossil Gymnospermous seeds Stephanospermum , the opinion 
was expressed that a considerable number of the radially sym¬ 
metrical forms of seeds of Permo-carboniferous age (Radiosperms) 
possessed the same fundamental type of organisation as Stephano¬ 
spermum itself. 1 The present communication deals with two addi¬ 
tional seeds from this provisional group, viz. Trigonocarpus and 
1 Oliver, Trails. Linn. Soc. Second Series, Botany, Vol. VI., p. 392. 
