Vol. XVIII, pp. 201-202 September 2, 1905 



PROCEEDINGS 



OF THE 



BIOLOGICAL SOCIETY OF WASHINGTON 





A NEW PUOSERPINOID LAND 8HELL FRO.M BRAZIL. 

 BY WILLIAM HEALEY DALL. 



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

 fer from ordinary Proserpina by having the columella truncate 

 and no parietal or palatal lamina^. It has not been figured and 

 I have not seen specimens, l)ut from the characters of a shell 

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

 subordinate subdivision of Proserpina. 



From the calcareous l)anks of the arroyo of the Rio Chico at 

 Paraguassii, State of Bahia, Doctor Orville A. Derl)y obtained 

 a small apparently sul^fossil 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 I)e 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- 

 v]\a is taken up by it parallel to the base of the apin'ture 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 



36— Proc. Biol. Soc. Wa.sh., Vol. XVIII, 1905. (201) 



