228 M. YOKOYAMA; MESOZOIC PLANTS 



reason why we can not unite the two, especi-.illy when we consider that 

 the shape of the segments in this genns is genera]]}^ very variable. 



All the specimens hitherto found in Japan belong to the form 

 Avith narrow leaves, that represented in tig. 14, Vl. XX being the 

 broadest. 



Loc. — Yuasn, Kataji, Tôgodani ; numerous. K;igahara ; rare. 

 Tlie plant is alscj mentioned as from Hiura Ijy Xathorst. 



23. Nilssonia pterophylloides m. 

 PI. XXII, Figs. 8-10 ?]. XXV. Fig. 7. 



Leaf eloiKjatcd (jraduallii tctpcrüiij antcriorh/ and endiiuj in a terminal 

 segment, deeph/ and reijidarh/ segmented; segments alternate, directed slighthj 

 fortrard, linear, yarcdled sided, apex ohtusc or ohtusehj pointed; veins ßne, 

 paralled, simple, 8-10 in niimher. 



Althongii this plant looks like rteroplujllum, the insertion of the 

 leaf on the rachis distinguishes it from the latter genus. 



The segments are all regular, narrow, parallel margined, o-4 mm. 

 in breadth, nnd standing inclined at atjout 70° to the moderately strong 

 rachis. The a})ex is obtuse in those at the posterior part of the leaf 

 and more pointed in those at the anterior part of it, and their line of 

 meeting on the surface of the rachis appears to ]ia\e Ijeen zigzag, as 

 seen in fig. 10, ]>!. XXII. 



I am acquainted with no form of the genus which ca.n be directly 

 compared with our species. Indeed, Zamile>< gracilis Kurr (Ueitr, z. foss. 

 Flora d. Juraf<:>rm. Wiirtt., p. 11, pi. I. fig. 4) and I'teroplujllum 

 pecten Lindlcy and Ilutton (Fossil Flora of Great Ihätain, vol. 11, 

 ]). 10-) greati}" i-esemble the Japanese form, as far as their external 

 appearance is concerned, but according to Schimper (Zittel, Handbuch 

 der Palaeont(jlogie, Abth. Palaeophytologie, p. l2i^o) they both belong 



