MESOZOIC PLANTS FKOM NAGATO AND BITCHU. 13 



species. Fig. 1 shows the back-side of a leaf while fig. 8 shows 

 the upper or front side of the same. The midrib, though not 

 very strong, is rigid with lateral veins, either at nearly right 

 angles to it, or slightly inclined forward. The leaf seems to have 

 been either entire or only partly segmented. 



The already known form of Nilssonia which can be compared 

 to the present one is Nilssonia polymorpya Schenk (Nathorst, 

 Beitr. z. foss. Flora Schivedens, pi. XI) from the Ehsetic of 

 Europe. 



5. PODOZAMITES LANCEOLATÜS (Lindl. et Huit.) 

 PL III. Fig. 5. 



A leaf lacking the apical portion. The general outline and 

 fine parallel longitudinal veins, numbering about 25, show that 

 it belongs to the above named species of Podozamites, widely 

 distributed in the Rhœtic as well as in the Jurassic. 



Although the above five plants are by no means decisive 

 in determining the age of the bed in which they occur, yet 

 their general character indicates that they belong most likely to 

 the Rhœtic. This is supported, not only by the occurrence of 

 anthracite layers as in the Rheetic of Nagato, but also by the 

 presence of a schalstein above, a rock which exhibits a great 

 similarity to the so-called Inkstone (schalstein) of the Inkstone 

 Series of the latter place. And as the lower part of this series 

 has already been proved to be Liassic, the schalstein of Nariwa, 

 if not entirely, at least its lower part may also be looked upon 

 as belonging to the same age. 



