164 



MORPHOLOGY OF GYMNOSPERMS 



the details of the reproductive structures is a very scanty one for so 

 great a group, and leaves very much to be desired. 



I. The vegetative organs 



The Cordaitales were tall and slender trees, the trunks often reach- 

 ing a height of 10 to 30 m. before branching (fig. 195). This long 



slender shaft (60 cm. or 

 more in diameter) bore a 

 dense crown of branches, 

 on which were produced 

 a great abundance of 

 large and simple leaves. 

 No such habit is known 

 among existing gymno- 

 sperms. Scott says (8) 

 that the short-leaved 

 species might suggest 

 Agathis or some forms 

 of Podocarpus, both 

 coniferous genera of the 

 southern hemisphere; 

 " but the large-leaved 

 species must have had 

 a habit very different 

 from anything which we 

 are accustomed to associ- 

 ate with gymnosperms at 

 the present day." The 

 branching habit, at least, 

 suggests Coniferales 

 rather than any of the 

 cycadophytes; and the 

 same may be said of the 

 simple leaves, but their 

 size is far beyond that 

 attained by the leaves of 

 conifers. 



Fig. 195. — Dorycordaites sp.: restoration, 

 showing roots, trunk, and crown, the latter com- 

 posed of branches bearing large lanceolate leaves 

 and clusters of strobili. — From Scott's (25) modi- 

 fication of Grand 'Eury's figure; the modifica- 

 tion consists principally in shortening the trunk, 

 which is many times longer than represented here. 



