196 



ARRANGEMENT OF PLANTS OF THE COAL. 



JEthophyllum, ecMnostacTiys, and pal&oxyris. One species 

 of each in the new red sandstone. 



Plants, the affinity of which has hitherto been regarded as 

 uncertain, but which are now referred with great probability 

 to the dicotyledonous division. 



Sigillaria. Rhytidolepis, alveolaria, favularia, catenaria, 

 &c., of Sternberg. Stem conical, 

 deeply furrowed, not jointed; scars 

 placed between the furrows in 

 rows, not arranged in a distinctly 

 spiral manner, smooth, much nar- 

 rower than the intervals which 

 separate them. 



About forty species in the coal 

 formation.* 



Volkmannia. Stem striated, 

 articulated ; leaves collected in 

 approximate, dense whorls. These 

 are considered to be, probably, the 

 leaves of calamites. 



Carpolithes. Under this name 

 are arranged all the fossil fruits to 

 which no other place is assigned.! 

 ARRANGEMENT or THE PLANTS OF THE COAL. The 

 most common of the coal plants may be classified under 

 the following divisions : First, ferns and sigillarice. 

 Secondly, lepidodendra, a doubtful genus, provisionally re- 

 ferred to lycopodiacece ; but, by Corda, ascribed to crassulacecB. 

 Thirdly, calamites, allied to equisetacece. Fourthly, coniferous 

 plants. Fifthly, stigmaria, which appear to be an extinct 

 family. 



I. FERNS AND SIGILLARIA. The leaves of flowerless 

 plants differ from true leaves in many particulars, and are 

 therefore called fronds. The genera of fossil ferns have been 

 determined by the characters of these fronds, such as their 

 mode of attachment to the racJiis or stem, their shape, their 

 method of branching, and the way in which the veins are 

 distributed. 



FIG. 132. Sigillaria organum. 



Pict. Atlas, pi. xix., xx., xxiv., p. 200, figs. 3, 4, 5, and 6. 

 f Pict. Atlas, pi. xxxiii. 



