THE CYCLOPHORTD LAND MOLLUSCKS OF AMERICA 137 



"The lingual teeth are 3. 1. 3, in arched rows : central broad, triden- 

 tate; 1st lateral broad, bidentate, with a base much produced out- 

 wardly; 2nd tridentate; 3rd much hooked and reflexed, tridentate." 



I collected semifossil specimens on the bluffs in a quarry on the 

 south side of the road between Pampator and Asuncion on Margarita 

 Island. I failed to find living specimens anywhere on the parts of the 

 island visited. 



INCERTICYCLUS, a pseudogeneric term 



Members of the family Cyclophoridae as a rule require a knowledge 

 of the operculum to enable one to assign them to the proper generic 

 and subgeneric groups. Since specimens not infrequently drift into 

 museums without this dooi', and the rest of the shell characters may 

 fail to enable one to locate the shell in question, I propose the above 

 name as a superspecific designation for species that have been 

 christened but that in our monographic endeavors we are unable to 

 locate properly for lack of the characters mentioned. 



Incerticyckis is not to be considered a genus, nor is it ever to have 

 a type, but is to remain an open catch-all into which we may place 

 those species the position of which we are uncertain. When the neces- 

 sary characters have been adduced these species can be properly 

 aligned, taken out of Incerticyclus, and when new material without 

 opercula is received, it can be placed in this group. 



I am placing the following species in Incevticyclus : 



INCERTICYCLUS BAKERI (Simpson) 



Plate 18, Figures 1-3 



1895. Neocyclotus {PtychocochUs)bakeri Simpson, Proc. U. S. Nat. Mus., vol. 17, 

 p. 440, pi. 16, figs. 1, 2. 



Shell large, helicoid; nuclear whorls lost. The early postnuclear 

 whorls are marked by wavy or slightly zigzag, retractively slanting, 

 slender axial riblets, which are well developed, quite regular and 

 regularly spaced, and separated by spaces about as wide as the riblets. 

 On the last half of the last turn, however, there appears another 

 type of sculpture consisting of strong wrinkles, the first part of 

 which is retractive, then vertical, then again sloping retractively 

 to the periphery. These wrinkles vary materially in strength. 

 Suture moderately well impressed. Periphery well rounded. Base 

 well rounded, openly umbilicated, and marked by decidedly retrac- 

 tively curved, very regular ridges, which pass over the umbilical 

 angle strongly onto the umbilical wall. These ridges are about as 

 wide as the spaces that separate them. In addition to this the entire 

 base is marked by fine incremental lines. There is scarcely a sug- 



