56 M. YOKOYAMA. 



rhachis, the auriculation of the basal corners, and in the general mode 

 of venation, but is decidedly distinguished in having a less number of 

 coarser veins with a correspondingly less number of nets, and in having 

 the leaflets set more closely together. Feistmantel indeed figures 

 leaflets which show a small number of aréoles (c. g. Gycadcen- 

 gatlungen, pi. IV, fig. 7, VI, 4); but all of these pertain to much 

 smaller forms. Our specimen shows larger leaflets with few 

 nets. Therefore it is quite unsafe even to create a variety out of our 

 specimen, the number and size of veins being considered as very im- 

 portant characters in the discrimination of fossil plants. However, 

 there is no doubt that our plant is very nearly related to Dictyozamites 

 indiens, and I regard it as belonging to the same genus. 



Our specimen is very meagre. The apices of the leaflets could 

 not be well exposed, therefore it is very difficult to decide whether 

 they ended acute or obtuse. 



Very rare. Loc. — Shimamura. 



Fam. 2. Cycadeae, 



7. Cycadeospermum Sap. 



37. Cycadeospermum japonieum Geyl. 



Cycadeospermum japonicum-Geyler, Ueber foss. Pflanz, a. d. Jura- 

 form. Jap., p. 231, pi. XXXIII, fig. 5. 



I have not been able to find any specimen referable to this 

 species. 



Order 2. Coniferae- 

 Fam. 1. Taxaceae. 

 1. Ginkgodium m. 



Leaf coriaceous, entire or lobed, gradually narrowed towards ike base 



