Seed-Plants 139 



is probably a remote one. There does not, however, 

 seem to be any strong evidence of any direct rela- 

 tion with any other existing plant, although for- 

 merly Ginkgo was associated with the conifers, and 

 there are some undoubted resemblances between 

 them, such as the character of the wood and the 

 seed. For a long time it was supposed that the tree 

 was extinct in a wild condition, but it has finally 

 been discovered growing wild in certain parts of 

 western China. 



CONIFERALES 



The great majority of the living gymnosperms 

 are Conifers, the ordinary cone-bearing ever- 

 green trees, which in certain regions, like the Pacific 

 Slope of North America, are the dominant forest 

 trees. There is much difference of opinion as to 

 the origin of the conifers, but we believe that the 

 weight of evidence is in favor of their derivation 

 from some types allied to the tree-like club-mosses 

 of the Paleozoic. The great club-mosses, like 

 Lepidodendron and Sigillaria, although they were 

 undoubtedly different in many ways, nevertheless 

 recall in certain respects the modern coniferous 

 trees. Like the latter, they developed a secondary 

 growth in thickness, and the cones are quite sim- 

 ilar. As some of these Paleozoic club-mosses are 

 known to have developed seeds, which recall those 

 of the living Araucaria, the derivation of the latter 



