CEPHALOPODA FROM THE HOKKAIDO. 13 



GAUDRYCERAS Ghossouvre emend. Kossmat. 



We have one addition to make to the remarks of Kossmat 

 on the genus Gaudryceras, and that is respecting its suture line. 

 Putting aside the question whether Gaudryceras is a well defined 

 genus or not, it has been divided into two well marked sections, 

 to the first of which belong G, Ayassizianum Pictet^^ from the 

 upper Gault of Switzerland and G. 3Iarut Stoliczka"^ from the 

 Utatur group of South India. The former shows the antisiphonal 

 lobe prolonged and reflected on the preceding septum as illustrated 

 in detail by Quenstedt."^ ; Ijut the suture line of the latter has been 

 only partly figured. The second group, or the group of G. Sacya, 

 contains more than thirty species, of which there are only two, — 

 G. vertebratum Kossmat^' and G. varayurense Kossmat'^ — whose 

 lobes have been examined ; but as to the septal lobe in these two 

 species, there exists neither a drawing nor a description. However, 

 after careful examination of several Japanese species of Gaudry- 

 ceras, the writer was able to find three species showing the septal 

 lobe just as in G. Ayassizianum Pictet. These three are G. 

 tenuiliratum, m., G. striatum Jimbo sp. var. pictum m. (PL IV. 

 fig. 6 c) and G. limatum m., each representing a particular type 

 in the group of G. sacya. The presence of the septal lobe in 

 the above three and in G. Ayassizianum leads us to presume that 

 it is a character common to all species of Gaudryceras although 



1) J. F. Pictet et W. Roux: ^Mollusques fossiles des Grès Verts des environs de Genève. 

 1847-53. P. 47, PI. IV. figs. 3, 4. 



2) Stoliczka: 1. c. p. 1Ü2, PI. LXXIX., lig. 1.— Kossmat: 1. f. p. 34 (130). 



3) F. A. Quexsteut: llandljucli d. Petrefuktenkunde. III. Auflage. ;SS5. P. 579, Pi. 

 XLV. fig. 11. 



4) Kossmat: i. c. p. 2G, PI. IV., lig. 2. 



5) Kossmat: 1. c. p. 3U, PI. 1., ligs. 4, 5. 



