CUBAN ANNUDARIIDAE — TOERE AND BAETSCH 161 



RHYTIDOPOMA CLATHRATUM CLATHRATUM (Gould) 



Plate 11, Figtjbe 15 



1842. Cyclostoma dalhratum Goulo, Boston Jouru. Nat. Hist., vol. 4, cover to 



No. 1. 

 1856. Ctenopoma clathratum Pfeiffer, Malakozool. Blatter, vol. 3, p. 59. 

 1858. Cyclostoma denegatum Poey, Memorias sobre la historia natural de la isla 



de Cuba, vol. 2, pp. 2, 23-24. 

 1920. Rhytidoporna clathratum Henderson and Bartsch, Proc. U. S. Nat. Mus., 



vol. 58, p. 69. 



This race occupies the region about Retire, Cohseo, Bellamar, 

 Matanzas, Cahmete, and Cardenas; it was described from Retiro. We 

 have selected a specunen from that locality for our figure. This race 

 most nearly resembles R. clathratum candelaense but it is distinguished 

 easily from candelaense by the much feebler development of the axial 

 ribs at the summit, by the less strongly developed threads in the 

 umbilicus, and by lacking the weak fluting of the inner lip of the outer 

 peristome. 



The specmien figured, U.S.N.M. No. 203630, has 80 axial ribs on 

 the first of the remaining turns, 120 on the second, and 122 on the last. 

 It has 3.8 whorls remaining and measures: Length, 10.6 mm.; greater 

 diameter, 5.8 mm.; lesser diameter, 5.0 mm. 



Gundlach says of the animal: "Nearly colorless or tmged with violet. 

 Neck orange. Tentacles short, lemon colored." 



RHYTIDOPOMA HESPERICUM, new species 



Plate 11, Figure 3 



Shell very elongate-ovate, thin, translucent, horn colored with the 

 plug showing through the substance of the shell as an oblique brown 

 line. Nuclear whorls decollated in all our specimens. Postnuclear 

 whorls strongly inflated, well rounded, and marked by very poorly 

 developed, almost vertical axial riblets, of which 78 occur on the first 

 whorl and 77 on the last turn. These riblets become thickened and 

 hollow at the summit, but hardly form what might be termed cusps. 

 The spiral sculpture consists of almost obsolete threads, which are 

 scarcely indicated on the last whorl, while on the early whorls they 

 render the axial riblets slightly nodulose. Suture very strongly con- 

 stricted. Periphery strongly rounded. Base short, strongly rounded 

 and marked by the feeble continuation of the axial riblets, with 

 scarcely any indication of spiral threads on the umbilical wall. The 

 last whorl is decidedly solute and strongly deflected. Aperture very 

 broadly oval; peristome double, the inner decidedly exserted, almost 

 straight; the outer projecting only a trifle beyond the inner, forming 

 a mere ring about it. Operculum typically rhytidopomid. The 

 siphon has its origin at the posterior angle of the aperture a little 



