CEPHALOPODA FPvOî\[ THE HOKKAIDO. 9 



18 (|uitc obvious. In tlio Indian species, tlic niinil)er of ribs on 

 tlie upper side of the wliorl is nearly equal to that of the ribs 

 on the lateral side, or to that of the tubercles arranged in two 

 rows between the upper and lower series of ribs, l>ut moi-e 

 numerous than that of the tubercles in the lowest row. 



Locality and horizon : — This majestic form of Turrllitei< is 

 at present represented only by a single specimen which has been 

 found by J\lr. Komota in a marly nodule found Itolow a cliff of 

 the Ikushum])ets directly above the coal mine. 



The matrix of this specimen is a sandy marl, dark grey in 

 color, and compact in texture, agreeing in every respect with that 

 of the nodules in the sandstone of the cliff above cited. There- 

 fore there is no dou])t that the specimen came from that locality, 

 as is also showu by the presence of an impression of Blargarita 

 funiculclta Yokoyama on the matrix of this specimen, a (lasteropoda 

 very common in tlie above sandstone. This sandstone cliff is the 

 chief locality of the typical fossils of the lower Acanthoceras-zone. 



The writer has much pleasure in associating with this species 

 the name of its collector JMr. Komota who w\as kind enough to 

 present it to the museum of the Geological Department of the 

 Tokyo University. 



HELICOCERAS SCALARE m. 



PI. III., figs. 2 and 3. 



Shell helicoid, forming a. widely open coil ; either sinistral 

 or dextral. Whorls circular or subcircnlar in section, gradually 

 enlarging anteriorly. Surface with numerous transverse ribs. 



