490 



CALIFORNIA ACADEMY OF SCIENCES [Proc. 4th Ser. 



Living: Monterey, California (!), to San Diego, Cali- 

 fornia ( !) ; between tides to 15 fathoms. 



Material Examin ed : 



Remarks: This species or subspecies has already received 

 some attention in the course of the discussion of the last species, 

 but a few more notes deserve to be recorded. 



For one thing I am not yet altogether sure that mirabilis is 

 entirely worthy of subspecific separation from palmulatus Car- 

 penter. On the other hand I am no more positive but that it 

 may eventually prove specifically distinct. This seems para- 

 doxical but is a situation which logically follows from the 

 conflicting evidence afforded by our scanty data. While it is 

 true that the majority of the fossil specimens fall without 

 debate under Pilsbry's diagnosis, and it further appears that 

 none of the specimens, unless very doubtfully some of the juve- 

 nals, accord entirely with his description of typical palmulatus. 

 still the number of specimens which in one or more particulars 

 are intermediate between the two is legion. My experience 

 with recent specimens is that they are often even more trouble- 

 some to separate. Without exception all the characters de- 

 pended upon to distinguish the two forms are subject to much 



