JURASSIC PLANTS FROM KAGA, HIDA, AND ECHIZEN. 23 



2. Thyrsopteris prisea Eichiv. sp. 

 PL I, fig. 3, 3a, 4. 



Thyrsopteris prisea — Heer, Beitr. zur Juraflora Ostsib. u. d. 

 Amurl., p. 86, pi. XVIII, fig. 8. Schmalhausen, Nachtr. zur Jura- 

 flora des Kohlenbassins von Kusnezk am Altai, p. 548, pi. I, fig. 2-4. 



Sphenopteris pmca-Eichwald, Lethaea Rössica, II, p. 14, pl. IV, 

 fig. 2. 



Although our specimens are by no means complete, yet the 

 elongated pinnae, the ovately-triangular and pinnatifid pinnules, and 

 the obtuse lobes, together with the dichotomous tertiary veins, suffice 

 l. ) show that the species, first found at Kamen ka and afterwards in 

 ►Siberia, is also represented in the Japanese Jurassic system. From 

 the preceding species, to which this is very closely akin, it is distin- 

 guished in having the tertiary veins dichotomous, as shown in 

 fio-, 3a. Loc. — Shimamura. 



3. Thyrsopteris Kagensis m. 

 PI. I, fig. 6, 6a. PI. XI, fig, 7. 



Frond bi-tripinnated ; pinnae elongated; pinnules coriaceous, alternate, 

 acutely direeted forward, ovate-lanceolate, gradually tapering below and 

 contracted at base, lobed or even pinnatipartite ; lobes or partitions narrow, 

 acutehj directed forward, acute at apex ; veinlets dichotomous. 



This fern seems to have been twice to thrice pinnated. Some of 

 the upper part of the upper pinnae show quite an entire margin, 

 while others are furnished with lobes. A pinna in the lower part of 

 the frond (PI. I, fig. 6, left) however exhibits lobes nearly separate 

 from one another, so that each of them here takes the place of the pin- 

 nules above. The substance of the pinnules seems to have been 

 tolerably thick in consistence. A vein given off into each lobe or 

 partition again dichotomizes as represented in fig. 6a. These veinlets 



