164 CALIFORNIA ACADEMY OF SCIENCES. 



none of the specimens collected by the Academy's expe- 

 ditions agree exactly with the types, although some show 

 no more variation than we see in varieties of B . xantusi. 



BuLiMULUS DECiPiENS J. G. Coopcr, n. sp. 



I propose this name for a new form, of which three 

 specimens were brought from San Lazaro Mt. They 

 were living but apparently quite young, too immature to 

 figure. The largest is nearly of the size and form of B. 

 ■pilula as figured, but still more globular, being shorter 

 and wider, with three whorls. It is more Heliciform, 

 much resembling H. californiensis Young, and like that 

 has a single vittiform band around periphery, which be- 

 comes hidden in the suture of two upper whorls. The 

 band is, however, paler than the brownish epidermis 

 (faded in alcohol ?). To prove their affinity to the Bu- 

 limuli of the region, they show the vertical riblets on i}4 

 apical whorls, and a more sunken nucleus than in the 

 Helix. No single -banded Helix is known for 200 miles 

 north of the locality of this species. 



BuLiMULUs INSCENDENS W. G. Binney. 



About 45 specimens were brought from San Lazaro, 

 representing all its varieties, while the other large species 

 were quite rare there compared with other localities. 



Genus Plicolumna J. G. Cooper. 

 In article 2, p. 215, vol. iii, 2d series, I referred to Co- 

 lumna, the species before called Rhodea var. ramentosa 

 by me in article i, p. 102, vol. iii, April, 1891. The 

 original Columna (Perry), is a quite different shell, but 

 other authors have included with it shells with plications 

 on the body whorl, complete spire, etc., as in my species. 

 Dr. Dall, having succeeded in finding enough of the soft 

 parts, in specimens I sent, to examine microscopically, 

 writes as follows : 



