28 Art. 8. — A. Kryshtofovich : 



1871. Heer, Flora von Quedlinburg, p. 4, pi. I, f. 1, 1 b, 



1874. Heer, Die Kreideflora der arctisclien Zone, F. F. xV., vol. Ill, p. 44, 



90, 97, pi. IV; V; VI, f. 1-3; VII, f. 2; XXV, f. 1-3; XXVI, 



10-13. 

 1876. Heer, Beitr. zur foss. Fl. Spitzbergens, F. F. A., vol. IV, p. 49, pi. 



XXXII, f. 6, 7. 



1882. Heer, Die fossile Flora Grönlands, F. F. A., vol. VI, Abt. 2, p. 36, 

 pi. III. f. 2. 



1883. Heer, Flora der Patootscliicditon, F. F. A., vol. VII, p. 7. 



1888. A^ELENOVSKV, Die Farne der böhmischen Kreideformatiou, p. 6, pi. III, 

 f. 7. 



1889. Stur in Toula, Geologische Untersuchnugen ini Zentr. Balkan, p. 27- 

 29, p. 33. 



1896. Newberry, Flora of Amboj Clays, p". 37, pi. III, f .5 b. 



1899. Ward, The Cretaceous Formation, p. 664, pi. CLXII, f 9. 



1904. Berry, Additions Flora Matawan Form., p. 67, pi. IV, f 6. 



1905. Zeiller, Sur quelques empreints des vége't. supracrét. des Balkans, p. 649. 



1906. Berry, Contrib. to the Flora of the Atlant. Coast, ]). 164. 

 1911, Berry, The Flora of Raritan Formation, p. 64. 



Locality : Erikson's coal mine. 



This typically Cretaceous and most important form has been 

 chiefly observed in the light-grey sandstone of this mine, belonging 

 to the lowest known Cretaceous horizon of Russian Sakhalin, together 

 with other different species of Gleichenia ferns, partly determined. 



This species shows, in some of the impressions, two rows of 

 sori, one on each side of the midrib. G. Zippei is represented in 

 all Cretaceous floras of Greenland, from Kome up to Patoot. In 

 North America, it was recognized in floras from the Black-Hills 

 up to Raritan, Dakota and Magothy of Delaware and New- Jersey, 

 besides in the Upper Cretaceous of the West. In Europe, the 

 same species was observed in t!ie Cenomanian of Bohemia and in 

 the Senonian of Saxony, Bulgaria and Bohemia. 



