THE CYCLOPHORID LAND MOLLUSKS OF AMERICA 5 



KEY TO THE SUBGENERA OF FARCIMEN 



Peristome thickened and reflected Farcimen 



Peristome not thickened or reflected Neopupina 



Subgenus Farcimen Troschel 



In the subgenus Farcimen the peristome is thickened and reflected. 

 The group is peculiar to the island of Cuba. 



Type: Turho tortus W ood^^ Farcimeti (Farcimen) tortum (Wood). 



FARCIMEN (FARCIMEN) PSEUDOTORTUM, new species 



Megalomastoma tortum of many authors, not of Wood, which equals Farcimen 

 apertum Poey. 



Shell elongate-ovate, the early whorls varying in color from yellow 

 to pale orange. Nuclear whorls 1.8, well rounded, smooth. Postnu- 

 clear whorls well rounded, narrowly shouldered at the summit; the 

 early turns are marked by rather distantly spaced, slender, retractively 

 curved axial riblets. These riblets on the succeeding turns become 

 more closely approximated and less regular, and on the last wliorl are 

 less expressed than on the other whorls. In perfect specimens there 

 is a faint indicaton of obsolete spiral hairlines, at least on the early 

 turns. Suture rendered conspicuous by the shoulder at the summit. 

 Base protracted, tapering fairly abruptly toward the open umbilicus. 

 The umbilicus is bounded by an obsolete carina. Within this the um- 

 bilical wall appears slightly excavated and is marked by incremental 

 lines. Aperture almost circular ; peristome thickened, heaviest at the 

 posterior angle and at the junction of the basal lip with the columella, 

 and narrowest on the parietal wall. Operculum typically farcimenid. 



This species is the one that has been considered by many authors 

 to be F. tortmn. We have explained under that sj^ecies why we do 

 not agree with this determination. F. (F.) pseudotortum resembles 

 most nearly forms of F. (F.) ungula (Poey), from which, however, 

 it is easily distinguislied by the fact that tlie aperture is not protracted 

 into a clawlike element at the junction of the outer and basal lip. 



We are recognizing three subspecies, all occupying parts of Oriente 

 Province, which the following key will help to differentiate: 



KEY TO THE SUBSPECIES OF FARCIMEN (FARCIMEN) PSEUDOTORTUM 



Umbilicus very narrow. 



Shell large, height more than 24 mm pseudotortum 



Shell small, height less than 20 mm turquinoeuse 



Umbilicus not very narrow bayamense 



