SEED-LIKE LYCOPODIACEOUS ORGANS 199 



In both genera the most important difference from 

 true seeds, such as those of the Pteridosperms, consists 

 in the fact that the sporophyll as a whole formed part 

 of the seed-like organ, and was shed together with it. 

 In other respects — the single megaspore, the integu- 

 ment, and the indehiscent character — the analogies 

 with seeds are complete. In the case of Miadesmia the 

 wide lamina of the sporophyll gave the organ the 

 character of a winged seed. 



x Sm. 



Fig. 84. — Miadesmia membranacca. Radial section of seed-like organ, t, tentacles ; 

 other lettering as in Fig. 83. X about 30. R. S. S. Coll. 2240. 



5. Bothrodendron. — The genus Bothrodendron, of 

 Lindley and Hutton, represents another group of 

 Palaeozoic Lycopods, very near Lepidodendron, though 

 differing from it in the surface-characters of the stem. 

 The genus is now well known, and presents several 

 points of interest. On the larger stems, the surface of 

 the cortex is smooth, the leaf-scars are very small, and 

 flush with the surface, for leaf- cushions were not 

 developed. This causes a striking difference in appear- 

 ance from Lepidodendron, though the leaf-scars are in 

 themselves quite similar to those of that genus, showing 



