FOSSIL PLANTS FROM NAGATO. ^43 



A fragment of ;i coar.sely toothed pinna, with teeth triangular, 

 ohtusely pointed at apex and slightly inclined forward, and with 

 reticulate venation, is undoubtedly a species of Dlctyophylluiii which 

 is at least very closely akin to DicfijopliiiUniii acntllohuin of the lihcL^tic 

 of Europe. In our only specimen tlie teeth are closer together than 

 in most of the figures given of this species, and the secondary veins 

 slightly zigzag. 



Besides occurring in the R luetic of Eiu'ope, this species has been 

 also described as occurring in that of the Albours Chain in I'ersia and 

 of Tongking. 



3. Dictyophyllum japonicum //. sp. 

 VI XXXIIL 



Although this is the most aJjundant of all the plants found at 

 Yamanoi, vet not a specimen was oljrained representing a complete 

 frond, all being isolated ])inna', which may l)e characterized as follows : 



Pinnie linear-lanceolate, ljroade:;t near the middle, slightly tai)er- 

 ing towards both ends, lobed exce[>t near the base where they are 

 simply wavy (jr entire; lobes more or less inclined forward, triangular 

 in shape, with the aiiterior margin straiglit or c(jncaAe, with the 

 posterior margin usually convex, and the apex obtusely pointed. 

 Ivhachis very stn^ng, straiglit or S(3mewdiat curved, running to the 

 apex of the pinnae ; secondary veins, coarse, slightly cr(j(jked or zigzag-, 

 directed forwai'd and going up to the apex of each lobe, thus forming 

 its median vein ; tertiary veins distinct, somewhat inclined anteriorly 

 and dichotomizing, the branches forming by their union with those of 

 the neighb(jurring ones coarse pentag(jnal or hexag(jnal nets, which are 

 usuallv drawn out in the direction of the median \'ein ; (piaternary 

 veins very fine, forming secondary nets within the primary ones. 



