LOWER CALIFORNIAN MOLLUSCA. 215 



CoLUMNA RAMENTOSA J. G. Cooper, 1891. Rhodca 

 californica var. ranientosa, J. G. C, in Proc. Cal. Acad. 

 Sci., Ser. 2, Vol. iii, p. 102, 1891. Mr. Eisen obtained 

 15 specimens of the same shell found by Bryant, as de- 

 scribed in the previous article, showing that to have been 

 at the extreme lowest point of their range. Only five of 

 them are entire, but most of them retain the fully-devel- 

 oped mouth. This shows that it has characters included 

 under Colunma, such as folds in the body-whorl, an oval 

 mouth with everted lip, and complete spire. The char- 

 acters of " Subgenus Rhodea," as quoted by Binney, 

 exist in this shell only while immature, so that if C . (Rho- 

 dea) californica retains them permanently it must be a 

 different species altogether. 



C. RAMENTOSA var. ABBREViATA J. G. C. A curious 

 variation, from similar heights on Sierra Laguna, with the 

 whorls reduced (from 13-15) to 8 or 9, and other differ- 

 ences. Five shells found, one with epidermis, but none 

 alive. Has nearly the aspect of Bulimtilus artemisia. 



Unfortunately, none of these retain the soft parts. The 

 shells will be figured in a future paper. 



Another new form of CylindrellidcB was found by Mr. 

 Eisen, which will also be described. 



Helix areolata Pfeiffer, 1845. Specimens of this 

 and its varieties have been received in large numbers by 

 the Academy, through many collectors and from the whole 

 west coast between Margarita Bay and latitude 31°. They 

 certainly do not show more extremes of variation between 

 this, "//. -pandorcE " and "/T. Icvis " than occur in local 

 forms of many others of our western species. A large 

 number was, as usual, brought from Margarita Island, 

 and, as usual, no other land-shells were found there, 

 though very thorough search was not- made. Its supposed 

 limitation to the west coast was, however, modified by the 



2d See., Vol. HI. ( 17 ) October 6, 1802. 



