114 



THE GEOLOGICAL HISTORY OF PLANTS. 



perhaps its most singular feature. They usually start 

 from the stem in four main branches, then regularly 

 bifurcate several times, and then run out into great 



Fig. 35. — Stem of Sigillaria Fig. 30. — Two ribs of Sigillaria Brownii. 

 Brownii. reduced. Natural size. 



cylindrical cables, running for a long distance, and evi- 

 dently intended to anchor the plant firmly in a soft and 

 oozy soil. They were furnished 

 with long, cylindrical rootlets 

 placed regularly in a spiral man- 

 ner, and so articulated that when 

 they dropped off they left regu- 

 lar rounded scars. They are, 

 in short, the Stigmarice, which 

 we have already met with in 

 the Erian (Figs. 38, 39). In 

 Fig. 33 I have endeavoured to 

 restore these strange trees. It is 

 not wonderful that such plants 

 have caused much botanical con- 

 Fig. 37.— Portion of lower troversy. It was long before bot- 



part of stem of S. Brownii. . J ° . 



Natural size. anists could be convinced that 



