SEED-LIKE LYCOPODIACEOUS ORGANS 197 



L. Wildianum is frequent in the more ancient Burntisland 

 deposits of Lower Carboniferous age. 



The cone of L. Lomaxi was first discovered by 

 the late Mr. G. Wild and Mr. J. Lomax, working 

 independently. 1 



Lepidocarpon no longer stands alone among Palaeozoic 

 Lycopods in possessing organs analogous with true 

 seeds. Another instance is afforded by Miadesmia 

 membranacea, the vegetative organs of which were 

 discovered by Bertrand in 1 894 in the calcareous nodules 

 of the English Lower Coal-measures. The stem is 

 very slender, and the plant appears to have been of 

 herbaceous habit. The stele is of simple structure, with 

 centripetal wood and no pith ; the cortex contains 

 trabeculae comparable to those of Selaginella. The 

 leaves appear to have been borne in four rows ; the ligule 

 is remarkably well developed, and the lamina is fringed 

 by a membrane one cell thick, breaking up into 

 uniseriate hairs at the margin. Within the last few 

 years a megasporangiate fructification has been dis- 

 covered, which is shown, by the structure of the ligule, 

 the fringed margin of the sporophyll, and other 

 characters, to have belonged to Miadesmia? The 

 fructifications are borne in a rather lax strobilus. Each 

 sporophyll bears a megasporangium, attached to its 

 upper surface at the proximal end, containing a single 

 megaspore, filling its cavity (Fig. 84). As in Lepidocarpon, 



1 See their note "On a New Cardiocarpon-heanng Strobilus," in the 

 Annals of Botany for March 1900 ; for the full description see Scott, " On 

 the Seed-like Fructification of Lepidocarpon," Phil. Trans. Roy. Soc. vol. 

 194, B, 1901. 



8 Miss M. Benson, "On a New Seed -like Lycopodiaceous Fructification," 

 New Phytologisl, vol. i. 1902. For the full paper see Phil. Trans. Roy. 

 Soc. B, 1908. 



