VOL. XVIII, PP. 201-202 SEPTEMBER 2, 1905 



PROCEEDINGS 



OF THE 



BIOLOGICAL SOCIETY OF WASHINGTON 



A NEW PROSERPINOID LAND SHELL FROM BRAZIL. 

 BY WILLIAM HEALEY DALL. 



The genus Cyane H. Adams, described in 1870, is said to dif 

 fer from -ordinary Proserpina by having the columella truncate 

 and no parietal or palatal laminae. It has not been figured and 

 I have not seen specimens, but from the characters of a shell 

 about to be described, it may be merely, as Tryon concluded, a 

 subordinate subdivision of Prosefpina. 



From the calcareous banks of the arroyo of the Rio Chico at 

 Paraguassii, State of Bahia, Doctor Orville A. Derby obtained 

 ji small apparently subfossil land shell, which has been sub 

 mitted to me for examination by Doctor H. von Ihering, Director 

 of the Museu Paulista, at Sao Paulo, Brazil. 



The specimen is of very much the same size and habit as 

 Proserpina depressa Orbigny, from Cuba, in which the columella, 

 if it may be so called, descends in an even curve from the pari 

 etal wall until it merges imperceptibly in the basal margin of 

 the aperture and bears at right angles to itself a small lamella, 

 which often lags behind so as to be but little visible from in 

 front of the aperture. But in the case of the shell from Brazil 

 the lamella is prominent and strong and the curve of the colum 

 ella is taken up by it parallel to the base of the aperture and 

 so near the basal margin that only a narrow notch exists be 

 tween them, giving the effect of an oblique truncation of the 

 pillar. This leads to the surmise, in the absence of a figure or 



:',f> PROC. BIOL. Soc. WASH., VOL. XVIII, 1905. (201) 



