CUBAN ANNUlJARIIDAE TORRE AND BARTSCH 221 



RHYTIDOTIIYRA BILABIATA BILABIATA (Orbigny) 



Plate 18, Figure 6 



1842. Cyclostoma bilabiata Okbigny, in Sagra's Histoire physique, politique et 

 naturelle de I'lle de Cuba, vol. 1, pp. 258-259, pi. 22, figs. 3-5, 8, 8'. 



1849. Cyclostoma salebrosum Morelet, Testacea novissima insulae Cubana et 



Americae Centralis, p. 23. 



1850. Cyclostoma dorbignyanum Petit, Journ. Conchyl., vol. 1, p. 46. 



1850. Choanopoma? bilabiatum Gray, Nomenclature of molluscous animals and 



shells in the collection of the British Museum, p. 52. 

 1852. Cistula? bilabiata Pfeiffer, Monographia pneumonopomorum viventium, 



vol. 1, pp. 271-272, in part. 

 1856. Ctenopoma bilabiatum Pfeiffer, Malakazool. Blatter, vol. 3, p. 59. 

 1863. Chondropoma bilabiatum Reeve, Conchologia iconica, No. 7. 

 1890. Ctenopoma bilabiatum Crosse, Journ. Conchyl., vol. 38, p. 276. 

 1920. Rhytidothyra bilabiata Henderson and Bartsch, Proc. U. S. Nat. Mus., 



vol. 58, p. 65. 



The typical subspecies was described from Pan de Guajaib6n. It is 

 loiown also from Hato Caimito, just west of Pan de Guajaib6n, and 

 from Sierra Chica, to the south. It has been found also at Cacarajicara, 

 to the northeast of Guajaib6n, and it extends southeast of Guajaib6n to 

 Rangel and the Rio Santa Cruz. 



From a nomcnclatorial standpoint this race has met with consider- 

 able difficulty, as is shown in our synonymy. It is distinguished by 

 being rather large, in having the apex bright rose-colored, with the 

 rest of the shell white. The last whorl is solute. The axial ribs are 

 rather closely spaced and are rendered vertebrated by the spiral 

 threads. On the early whorls the spiral sculpture is considerably more 

 pronounced than on the last. In strength and disposition of the axial 

 ribs this subspecies resembles R. bilabiata aurantiaca, from which it is 

 readily distuiguished by its white peristome. 



The specimen described and figured, U.S.N.M. No. 355155, was 

 collected at Sagua on the west side of Pan de Guajaib6n. It has a 

 little more than 4 whorls remaming and measures: Length, 14.9 mm.; 

 greater diameter, 9.7 mm.; lesser diameter, 8.0 mm. 



RHYTIDOTHYRA BILABIATA AURANTIACA. new aubspeciea 



Plate 18, Figure 4 



This race has a rather extensive distribution. We have seen speci- 

 mens from Sierra de Guane, Mendoza (Paso Real), Puerta de la 

 Muralla, Sierra de los Acostas, El Francisco, Sierra de San Carlos or 

 Luis Lazo, Sumidero, Isabel Maria, the mogotes east of Cabezas, and 

 Pan de Azacar. It therefore appears to cover the entire western part 

 of the Organos Mountains and the limestone blocks lying off that 

 region. 



