HARDWICKE'S SCIENCE-GOSSIP. 



121 



THE FLORA OF THE PAST. 



No. iir. 

 By Mrs. BODINGTON. 



,IIE Lycopods, re- 

 sembling giant club- 

 mosses ( ' ' ground- 

 pines " of Canada), 

 make their first 

 appearance in the 

 Devonian forests. 

 In structure they 

 much resembled the 

 modern iLycopods, 

 except that the con- 

 trivances resorted to 

 for supporting a 

 club-moss of tree- 

 like size, approxi- 

 mate in " structure 

 to the stems of exo- 

 genous trees of 

 modern times. The 

 plan is, in short, 

 the same, except that the tissues employed are less 

 complicated." Another link for the evolutionist ! 

 These Lycopods can only be compared in their 

 curious stiffness to the trees found in Noah's arks, 

 whilst they decidedly exceed Noah's ark trees in 

 clumsiness, as may specially be seen in any repre- 

 sentation of Sigillaria Brownii, a carboniferous 

 species. 



We now pass on to what is probably to most 

 people the most interesting period in the history of 

 fossil plants, the Carboniferous age, when our greatest 

 accumulations of coal were formed. The wide inland 

 seas of the Devonian and Lower Carboniferous Period 

 in America and Europe, were replaced by vast 

 swampy flats, moist and warm, swarming with 

 insects, millipedes and scorpions, and tenanted by 

 the first air-breathing vertebrates, the Labrinthodonts, 

 animals having affinities with both frogs and newts, 

 but now entirely extinct. In the Carboniferous strata 

 of the Rocky Mountains deep-sea conditions still 

 persisted ; a few leaves seem to have floated out to 

 sea, but there is not a vestige of coal. 

 No, 294.— June 1889. 



The trees which above all others seem to have been 

 the most valuable in the production of coal were the 

 Sigillariis and the Calamites ; the former related to 

 the Lepidodendra of the Erian and the modern club- 

 mosses, and the latter to our horse-tails. The 

 Sigillarise exhibit the enormous variety of species in 

 Carboniferous times, more than eighty species having 

 already been counted. So much do they "grade" 

 towards other forms, that they seem to make even 

 Sir J. W. Dawson's anti-evolutionary convictions 

 totter. He goes so far as to say that he believes 

 " there were three lines of connection between the 

 higher cryptogams and the phtenogams (flowering 

 plants) ; one leading from the Lycopods by the 

 Sigillaria; ; another leading by the Cordaites, and the 

 third leading from the Equisetums by the Calamites. 

 Still further back the Rhizocarps united the characters 

 afterwards separated into club-mosses, horse-tails and 

 ferns." He hastens to say that he "does not make 

 these remarks in a Darwinian sense ; " but methinks 

 I see the last stronghold of "special creation" 

 tottering to its fall. 



The Sigillarioe have " tall pillar-like trunks, often 

 several feet in diameter, ribbed like fluted columns, 

 and spreading at the top into a few thick branches 

 clothed with long scale-like leaves. They resemble 

 the Lepidodendra of the Erian age, but are more 

 massive, with ribbed instead of scaly trunks, and 

 longer leaves." These giant Lycopods derived their 

 distinguishing name from the rows of scars of fallen 

 leaves making seal-like impressions on their stems. 

 The wood is of a very low type of structure, although 

 the trunks are sometimes five feet in diameter, and 

 consists "principally of cellular and bast fibres with 

 very little true woody matter." To support a thick 

 trunk of so primitive a character, very complicated 

 roots were necessary ; and these, under the name of 

 Stigmaria, were long considered as the stems of some 

 aquatic plant. They usually start from the trunk in 

 four main branches, then regularly bifurcate several 

 times, and then run out into great cylindrical cables 

 running for a long distance, evidently intended to 



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