22 University of Michigan 



The type (fig. ii-/) measures: 



Altitude Diam. Length Width 



Height Maj.Diam. Aperture Aperture Operculum Operculum^ 

 3.05 93 (2.85) 38 (1.15) 104 (1.20) 46 (1.40) 72 (i.oo) 



The systematic position of this species has heen discussed in 

 an earher paper (1922), where a preliminary description of 

 the radula i§ given. The figure of the teeth, included here 

 (fig. iv-17), shows its close relationship to Lucidella. The 

 shell is certainly closest to that of Stoasioma domingcnsis Van- 

 atta (1920), but it is slightly larger, more depressed, and has 

 a larger number of finer, spiral riljlets than the species from 

 Santo Domingo. 



LiicidcUa {Pociiia) lirata (Pfr., 1847). 



\\'idely distributed, but especially abundant in damp and in 

 disturbed places : San Esteban, Palma Sola, Aroa, Estacion 

 Tachira, and La Frjia ; from damp, rich humus on mountain 

 slopes, in lowland forests and cacao plantations, in a spring 

 swamp, and in the damp depressions occupied by forest pools 

 during the wet seasons (H, I, b, 2, 5, 23, 35; II, b, 40; V, h, 

 2, 41 ; VI. c, 38; XIII, 20). These specimens are mainly quite 

 characteristic of L. Urata lirata, but a few show some approach 

 to L. lirata lamdlosa (Guppy, 1867) from Trinidad. 



For comparison, the radular formula (fig. iv-19) of two 

 dried specimens (A. N. S. P. 62062, St. Kitts, W. H. Rush, 

 1891) of L. plicatula christo/^liori Pilsbry (1897) is given: 



R; Ai/i; P.i/6-7; C1/5; D1/9; E; M11/3+ (42/4+)=53; (n?)- 



3 The altitude and diameter of the aperture are measured parallel 

 to the long and transverse axes of the shell. The length and v/uUh 

 of the operculum are measured along its long axis and at right an- 

 gles to it. The index of the diameter of the aperture is that dimen- 

 sion divided % the altitude of the aperture. The inde.x of the w'fllii 

 of the ojicrcuhim is the widtli divided 1)y the length. 



