Plate VI. 



(AU the specimens, here figured, are in Sei. Coll. Mus.) 

 Desmoceras poronaicum. m. Pp. 39-41. 



Figs. 1 a, b. Side and front views of the type from the Upper Ammonite- 

 beds of the Poronai, Ishikari Prov. Nat. size. 



Fig. 2. Diagram of a suture line, drawn from the same specimen, s. 

 siphonal line ; u.m. umbilical margin. x 3. 



Ammonites Kofoi m. F[). 26-27 



Fig. 3. Side view of the type. From the Yûbarigawa. Slightly restored. 



Nat. size. 

 Fig. 3 a. Cross-section of the whorl. Nat. size. 

 Fig. 4. Diagram of the suture line, drawn from the same specimen, s. 



siphonal line ; u.m, umbilical margin. x 2. 



Olcostephanus unicus m. Pp. 28-29. 



Figs. .5 a, b. Side and front views of the type. From the Takambets, 

 Ishikari, Prov. Nat, size. 



Nipponites; mirahilis m. Pp. 20-2.'). 



Fig. G. Diagram of a suture line, drawn from the specimen figured in PI. 

 IV. s. siphonal line. Nat. size. 



Heteroceras Otsukai m. Pp. 14-16, 



Fig. 7. Diagram of a suture line, drawn from the specimens figured in PI. 

 IV., fig. 2. s. siphonal line. Nat. size. 



Hderocerm Otfiiûxii var, mnJUcoi^tato.. Pp. 16-17. 



Fig. 8. Diagram of a suture Hue, drawn from the specimen figured in PI. 

 IV., fig. 3. s. siphonal line; a.s. antisiphonal line, x 2. 



