Occasional Papers of the Museum of Zoology 41 



The following, very artificial key, to the names in the group 

 of F. inca, is presented. The remarks, preceding the key to 

 the group of P. transhicida, also apply here. As the earlier 

 descriptions are very monotonous reading, and often difficuk 

 of interpretation, the characterization of each fresh lot as a 

 new species appears to he the customary procedure in this 

 group. 



A. Basal lip of peristome with a marked indentation, corresponding 

 to subcanaliculate last whorl (teratological? ; Cf. von Martens, 

 1890). 



B. With a dark, spiral band just below periphery and another on 

 base of the last whorl. Province Cauca, Colombia (about 



L 5, 77)- ^7-7 ; 169 (30) ; 4 



Neocyclotus caucaensis DaCosta (1901.) 



BB. No bands mentioned in descriptions. 



C. Smaller, distinctly flattened, less vaulted. Bay of Salinas, 



Costa Rica. 16.5; 176(29) 



( !) Cyclotus irregularis, var. pittieri Mart. (1890). 



CC. Larger; the oldest name. Costa Rica. 26; 162(42) ; 5 (von 

 Martens, 1890) (*) Cydostoma irregulare Pfr. (1855). 



AA. Basal lip of peristome normally entire. 



D. Periphery of last whorl angulate or subangulate. 



E. Obscure, cord-like development on periphery of last whorl; 

 color olive-brown, somewhat lighter below. Ambato, 

 Ecuador. 13.2; 163(21.6) ; 4J/2. Cyclotus past Crosse (1866). 



EE. Angulation more prominent; last whorl at least subcar- 

 inate. 



F. Shell much depressed ; growth-lines very prominent. 



G. ]\Iost depressed, rapidly increasing whorls ; castaneo- 

 fulvous with blackish carina. Colombia. 18.1 ; 202 

 (36.6); 41/2. . .Cydostoma laxatum Sowerby (1849)- 



GG. Depressed ; olivaceous with light, peripheral stripe and 

 darker band below it. Bogota, Colombia. 20; 180(36). 

 ...(!) Cyclotus filoliratus Sowerby (1892, P. Z. S.). 



FF. Less depressed shell ; growth lines fine above, but coarse 

 below (Cf. Hscheri). 



