GYMNOSPEEM^. 



Although the Gymnospermse are classed with Dicotyledons and with Exogens in 

 many Botanical Classifications, and are therefore placed in a higher scale than Monoco- 

 tyledons, no apology is needed in a palseontological treatise for introducing them next to 

 the lowest class, the Cryptogams. Lindley, in 1833, recognising their somewhat 

 anomalous characters, grouped the Cycadese, Coniferae, and Taxmese into a primary 

 division, called by him Gymnospermse, equal in value to the Exogens and Endogens, and 

 placed next the Acrogens or higher Cryptogams. They have since been variously placed ; 

 but, whatever value may be attached to them in classifications as a primary division, they 

 are now recognised to include the Cycadace^, the Conifers, and the GNETACEiE. 



The Gymnosperms so far exceed in antiquity either the true Dicotyledons or the 

 Monocotyledons, that it has long been felt that through them, if at all, the evolution of 

 Phanerogams from Cryptogams would be traced. Notwithstanding, however, that the 

 external resemblance of Cycads to Palms, and the similarity of certain Coniferae to 

 Perns and Club-mosses, had led to much speculation as to their derivation, no 

 satisfactory connection could be traced ; and although they have been often claimed 

 boldly as the connecting link between the highest and the lowest classes of plants, all the 

 evidence, when sifted, has hitherto proved at best negative ; and the early appearance in 

 geological time of so highly specialised a type of plant has consequently been made use of 

 by the opponents of evolution. Darwin, indeed, contrasted the direct fertilisation of 

 the naked ovule by the pollen, with the admirably ingenious contrivances by which many 

 other plants are fertilised by insect agency. " Can we consider," he says, " as equally 

 perfect, the elaboration by our fir-trees of dense clouds of pollen, in order that a few 

 granules may be wafted by a chance breeze on to the ovules ?" Lindley also considered 

 them analogous to reptiles in the animal kingdom ; but it seems to be reserved to 

 Saporta and Marion to bring to light the actual stages through which the evolution of 

 the Gymnosperms has taken place ; and as we have been led in their ' Evolution of 

 Cryptogams ' from the primeval Cellular Thallogen, step by step, through Vascular 

 Cryptogams up to the Gymnosperm, so may we hope that their forthcoming volume will 

 trace, as satisfactorily as they feel confident it will, the stages through which the 



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