438 PROCEEDINGS: BOSTON SOCIETY NATURAL HISTORY. 
The rarity of cephalopods is a notable feature of the fauna. The 
absence of such characteristic West Coast pelecypods as Daonella 
lommdi, Halobia superha, and Pscudomonotis suhcircularis would 
make its reference to any portion of the Triassic exceedingly improba- 
ble; similarly none of the cephalopods so abundant in the western 
Triassic was found here. 
Massachusetts Institute of Technology. 
Printed January, 1911. 
