MESOZOIC PLANTS FROM KOREA. 15 



eleven pinnne which arc close together are preserved on one side 

 of the rachis, meeting those of the other side along the median 

 line of its upper surface ; none of the pinnae are perfect ; they 

 vary in breadth from 1.5 to 2.5 mm. and are parallel sided, ex- 

 panding a little near the base where they are slightly decurrent. 

 The veins are fine, simple, and uniformly distant ; 5-8 in a 

 segment. 



This fern is not unlike Dioonites Kotdei Yok., but its im- 

 perfect preservation renders a strict comparison impossible. 



CTENOPHYLLUM, Sch. 



CTENOPHYLLUM (?) sp. 



PL IV., fig. 7. 



A slab of shale with a splendid example of Cladophlelm 

 koraiensis shows, besides, two fragmental impressions of pinnate 

 cycadean fronds. 



One of them bears about fourteen linear pinnae on one side 

 of the rachis, and the other four ; none of these pinnae are, 

 however, perfect. The rachis is stout, about limm. in breadth. 

 The pinnae attenuate but little toward the broken apex ; they 

 are very close together and alternate ; the mode of insertion 

 cannot be satisfactorily made out, the rachis showing only the 

 dorsal side. The veins are rather thick, 5-6 of them fork shortly 

 after leaving the rachis. The longest pinnae, also imperfect at 

 its apex, has a length of 1.2 cm. and a breadth of ca. 3 mm. 



