172 D- H. Scott. 



which is sometimes excellently preserved, and was already present iu 

 the earlier stage of the megasporangium before the integument had 

 been formed. The sporophyll, with its integumented megasporangium, 

 was shed entire, and appears to have been indéhiscent. Specimens 

 0Ï Lepidocarpon (probably referable to several species) are very common, 

 both in the Lower Coal-Measures and in the much more ancient 

 Lower-Carboniferous petrifactions from Burntisland in Scotland. The 

 analogies with true seeds, in the integument, the single megaspore, 

 and the indéhiscent character are evident; we are unfortunately 

 without any evidence as to the stage at which fertilization took place. 

 The fossil has long been known, but was formerly confused with the 

 Gymnospermous seed Cardiocarpon , with which, of course, it has 

 nothing to do. 



Microsporangiate cones, probably belonging to Lepidocarpon Lo- 

 maxi. the common Coal-Measure species, have been observed. They 

 are indistinguishable from the cones of a small Lcpidostrobus. except 

 that there are indications of an incomi)lete integument around the 

 microsporaugium. Lepidocarpon Lomaxi fre(iuently occurs in associa- 

 tion with Lepidodendron Harcourtii, and the agreement in anatomical 

 structure between the two fossils is sufficiently close to render their 

 connection probable. It would be a curious result, if this species of 

 Lepidodendron, so long emphasized by the B r o n g n i a r t School as the 

 type, par excellence, of a true Cryptogamic Lycopod, should turn out 

 to have borne so seed-like a fructification. If such organs had happen- 

 ed to be discovered in a Sigillaria they would no doubt, at one time, 

 have been regarded as decisive evidence of its Phanerogamic nature. 



The other genus of quasi-spermophytic Lycopods is very different 

 from the former. The vegetative organs of Miadesmia memhranacea 

 were discovered by Bertrand in 1894 in the calcareous nodules of 

 the English Lower Coal-Measures. The stem is exceedingly slender, 

 and there is every reason to believe that the plant was a small, 

 herbaceous form — almost the only instance of an herbaceous Palaeo- 

 zoic Lycopod with structure preserved. The stem, which has a simple 

 oligarch stele, bears numerous leaves, apparently arranged iu 4 rows; 

 each leaf possesses a relatively large and conspicuous ligule and is 

 fringed at the edges by a membrane, one cell thick, breaking up into 

 uniseriate hairs. This character renders the fossil easily recognizable, 

 even in minute fragments. 



A few years ago a megasporangiate fructification was found which 

 there are good reasons for attributing to Miadesmia ( B e n s o n , 1902). 

 The sporophj'll bears a ligule exactly like that of the vegetative leaf 

 of Miadesmia, and the lamina is fringed in the same way at the 

 margins. The megasporangium is attached, at the proximal end, to 

 the upper surface of the sporophyll, and contains a single megaspore, 



