16 ART. 2, H. YABE : CRETACEOUS 



Hauer^^ sp. from the Senonian of Go>ssau and France is also 

 referable to this subgroup. 



II. Subgroup of Gaudryceras crassicostatum Jimbö sp. 



Whorls compressed on the sides, with broad ribs and finer inter- 

 stitial ones. Suture line in young specimens more complicated 

 than in those of the first subgroup. The type is G. crassicostatum 

 JiMBö"^ sp. The two other species from the Hokkaido — G. densepli- 

 catum JiMBö^^ sp. and G. striatum Jimbö^' sp. — show a sculpture 

 somewhat deviating from this type species. Ammo7iites glanegensis 

 Redtenbacher^^ from the Gossau formation of the north-eastern 

 Alps, being intermediate between G. tenuiliratum and G. den- 

 seplicatum, forms a connecting link between this subgroup and 

 the preceding. G. subtililinealum Kossmat sp. is also probably 

 referable to this subgroup. 



III. Subgroup of Gaudryceras limatimi Yabe. 



The stride on the whorls in young specimens are so extremely 

 fine that the surface appears to be almost smooth. The adult 

 shells present ribs which are broad and elevated, and crow^led 

 together without any interstitial stride as in the foregoing subgroup. 

 Suture line very complicated, characterized by the bipartite second 



1) Fr. v. Hauer: Neue Cephalopoden der Gosaiigebilde. Sitznngsb. Akad. Wiss, 

 Wien. 1866. Bd. LUI. p. 7 (305), PI. IT., figs. .3-4. A. de Grossouvre : 1. c. p. 227, PI. 

 .XXVI., fig. 4; PI. XXXIX. 



2) Vide p. 29. 

 8) Vide p. 30. 



4) Vide p. 31. 



5) Anton Redtenbacher : Die Cephalopodenfaiina d. Gosaiischicliten in d. nordöst. 

 Alpen. Abh. d. k. k. geol. Reichsanstalt. Bd. V. Heft 5. P. 119, PL XXVII., fig. 3. 



