356 EXTINCT GENERA OF CONIFER/E. 



the stems, had undergone decomposition, during the interval 

 in which they were floating between their place of growth, 

 and that of their final submersion. 



M. Ad. Brongniart enumerates forty-two species of Si- 

 gillaria, and considers them to have been nearly allied to 

 arborescent Ferns, with leaves very small in proportion to 

 the size of the stems, and differently disposed from those of 

 any living Ferns. He would refer to these stems many of 

 the numerous fern leaves of unknown species, which resem- 

 ble those of existing arborescent genera of this family. 

 Lindley and Hutton show reasons for considering that Si- 

 gillariae were Dicotyledonous plants, entirely distinct from 

 Ferns, and different from any thing that occurs in the ex- 

 isting system of vegetation.* 



Favularia. Megaphyton. Bothrodendron. Ulodendron.f 



The same group of fossil plants to which Lindley and 

 Hutton have referred the genus Sigillaria, contains four 

 other extinct genera, all of which exhibit a similar dis- 

 position of scales arranged in vertical rows, and indicating 

 the places at which leaves, or cones, were attached to 

 the trunk. The names of these are Favularia, Megaphy- 



* "There can be no doubt," say they, (Foss. Flora, vol. i. p. 155) " that 

 as far as external characters go, Sigillaria approached Euphorbiae and 

 Cacteae more nearly than any other plants now known, particularly in its 

 soft texture, in its deeply channelled stems, and what is of more consequence 

 in its scars, placed in perpendicular rows between the furrows. It is also 

 well known that both these modern tribes, particularly the latter, arrive 

 even now at great stature ; farther, it is extremely probable, indeed almost 

 certain, that Sigillaria was a dicotyledonous plant, for no others at the pre- 

 sent day have a true separable bark. Nevertheless, in the total absence of 

 all knowledge of the leaves and flowers of these ancient trees, we think it 

 better to place the genus among other species, the affinity of which is at 

 present doubtful." 



t PI. 56, Figs. 3.4. 5. 6. 7, 



