12 APvï. 2. H. Y A BE : CRETACEOUS 



It is a young volution with tlie umbilicus 5.5 cm. wide and the 

 larger end 1.3 cm. bj-oad. The other one which is from the 

 /Scaph!tes-h(idH of the Opiraushibels, is a fragment of the septate 

 portion of a larger shell. 



The present species is evidently related to Heleroceras cendopse 

 Anderson'* from the Smith ranch, east of Pha-nix, Oregon, for 

 they have many points of resemblance in the general form and 

 size of the shell and also in the character of the ribs. Indeed, 

 the resemblance is so close that their separation into two distinct 

 species may be donl)ted. But according to the description of 

 Anderson, the American fjrni possesses periodic ribs whose 

 highest elevation is on the siphonal line and is not so elevated 

 on the upper side as in the Japanese specimens. Although the 

 difference seems to be tiitling, yet the writer considers it prudent 

 at present to regard them as two distinct species. 



The discovery of more materials from both sides of the Pacific 

 wdll doul)tless throw light on this question. 



Localities and horizons: — The lower horizon of the Pachydiscus- 

 beds of the Saushi-sanu.sliibe, Iburi Prov., and the fSc(fp/iik'S-hQds of 

 the Upiraushibets, Teshio Prov. (Jne specimen from each locality. 



HETEROCERAS (?» OSHIMAI m. 

 IM. III., ligs. 5 and C 



Shell tui-reted, sinistral ; vohilions free, especially near the 

 anterior end. Whorls growing slowly ; obliquely elliptical in 

 section ; the surface carrying both ribs and tubercles. Kibs 



1) Andkksok : Cretaceous Deposits of tin/ Fucllie Coast. Proc. Calif. Aead. Sei. old 

 Series. Vol. 11., no. 1, p. 'Jl, pi. LII., ligs. K.HMOl. 



