Fossil Vegetables of the Coal Formation. SSY 



gallery, almost at the height of the observer's eye ; towards its 

 base, it was about a foot in diameter, and appeared broken and 

 not naturally terminated ; it was, like all the stems deposited in 

 the direction of the strata, compressed to such a degree as to be 

 entirely flat. On following this stem in the gallery, I was as- 

 tonished to see that it attained, without interruption, a length of 

 more than forty feet ; its diameter diminished insensibly, so that 

 it was not more than six inches at its upper extremity ; but this 

 extremity, instead of terminating suddenly, was divided into 

 two branches, each of about four inches diameter, which sepa- 

 rated from each other, and were prolonged a few inches, when 

 they were interrupted by a fracture in the rock. I was not 

 able to trace beyond this point with certainty ; but it is never- 

 theless well proved that these stems, after attaining a great height, 

 finish, if not always, at least in some cases, with becoming fur- 

 cated, and probably dividing several times by dichotomy. It 

 is to this latter division of the stem that we must attribute the 

 rare occurrence of specimens presenting examples of it. On the 

 contrary, the great extent of the simple part of the stem of these 

 vegetables, must render the specimens of these portions of stems 

 very common in the rubbish extracted from mines. In the Sa- 

 genarias, on the contrary, where the stem appears to divide at a 

 small distance from the base, and to ramify a great number of 

 times, examples of these dichotomous divisions are of more fre- 

 quent occurrence. 



After having properly established the mode of division of 

 the stems which compose the genus Sigillaria, there remains for 

 us to determine, if, notwithstanding this dichotomous form, they ' 

 ought still to rank among the ferns, or if this character be suf- 

 ficient to separate them from these plants, among which no ex- 

 ample of the kind of structure in question is now observable. 



The mode of division of the stem does not appear to me to- 

 form a character of sufficient importance to induce a separation 

 of vegetables which have so many other characters common. We 

 see these two modes of structure united in the most natural fami- 

 lies of monocotyledonous plants ; and there is nothing in the 

 organization of the tree-ferns that appears to militate against 

 the possibihty of their having united, like these families, plants 

 with simple stems, and others with branched ones. Supposing 



