202 HEREDITY AND EVOLUTION IN PLANTS 



now in position to draw a fairly complete picture of the 

 plant as it must have appeared when living. 



"It was in effect a little tree-fern, with long, slender, 

 sometimes branched, stem, 4 centimeters or less in diame- 



FIG. 86. Lyginodendron oldhamium. Pinna of a microsporophyll, 

 found in an ironstone nodule. Before its identity was established this 

 specimen was named Ctossotheca Hoeninghausi. The somewhat peltate 

 fertile pinules on the ultimate branches, bear each a fringe of micro- 

 sporangia about 3 mm. long. The appearance has been likened to that 

 of a fringed epaulet. (After Scott, from a photo by Kidston.) 



ter, and provided with spines by means of which it prob- 

 ably climbed on its neighbors. The foliage was disposed 

 spirally and consisted of relatively very large, finely 

 divided fronds with small, thick pinnules with revolute 



