CEPHALOPODA FEOM THE HOKKAIDO. 41 



with some reserve. Also it may not be impossible, as it some- 

 times happens, that they are really individuals of one and the 

 same species at different stages of growth. However, for the pre- 

 sent, it seems preferable to treat them as two distinct species. 



Locality and horizon : — This species is known only from 

 two small, probably immature specimens, ol)tained near the source 

 of the Poronai, Ishikari Prov. At this place, they were found 

 in a pebljle of a marly module, the exact horizon in which they 

 occur being unknown, but it is almost certain that the nodule 

 was derived either from the lower part of the upper Ammonite- 

 beds or from a laver 1)elow it. 



