268 PROCEEDINGS OF THE NATIONAL, MUSEUM Vol.89 



axial ribs. Aperture broadly oval; peristome simple, auriculated at 

 the posterior angle. Operculum typically tudorid. 



This species is confined to Camagiiey Province. We are recognizing 

 two subspecies, which the following key and descriptions will help to 

 diflEerentiate: 



KEY TO THE SUBSPECIES OF TUDORAKAGUAYOTUDORA) CRIST ATA 



Spiral sculpture of last whorl obsolete cristata 



Spiral sculpture of last whorl consisting of low rounded threads... chorrillensis 



TUDORA (AGUAYOTUDORA) CRISTATA CRISTATA, new subspecies 



Plate 26, Figure 4 



This subspecies comes from San Martin de Biaya, 15 miles south of 

 Marti, Camagiiey Province. It is easily distinguished from T. {A.) 

 cristata chorrillensis in lacking the spiral threads on the last whorl. 



The type, U.S.N.M. No. 493434, has 6.5 whorls and measures: 

 Length, 12.8 mm. ; greater diameter, 6.2 mm. ; lesser diameter, 5.7 mm. 



There is considerable variation in size of individuals of this sub- 

 species. The smallest specimen has 6.2 whorls and measures: Length, 

 9.6 mm.; greater diameter, 5.7 mm.; lesser diameter, 4.9 mm. 



TUDORAI(AGUAYOTUDORA) CRISTATA CHORRILLENSIS, new subspecies 



Plate 26, Figure 6 



This subspecies comes from the Vereda del Telegrafo, Sierra del 

 Chorrillo, south-southeast of Camagiiey, Camagiiey Province. It is 

 readily distinguished from T. {A.) cristata cristata by the fact that the 

 whorls have low rounded spiral threads, which render the axial ribs 

 slightly sinuous. The spiral sculpture on the base is also much more 

 pronounced. 



The type, U.S.N.M. No. 493436, has lost the nuclear turns, the 5 

 postnuclear whorls measuring: Length, 13.3 mm.; greater diameter, 

 7.4 mm.; lesser diameter, 6.3 mm. 



TUDORA (AGUAYOTUDORA) CRASSIUSCULA, new species 



Plate 26, Figure 7 



Shell ovate, horn yellow, with interrupted spiral bands of brown. 

 The elements composing these bands are rather distantly spaced 

 and are arranged also in axial series. Nuclear whorls 2, inflated, 

 strongly rounded, microscopically granulose. Postnuclear whorls very 

 inflated, strongly rounded, marked by retractively slanting axial ribs 

 which are best developed on the early whorls and which become de- 

 cidedly enfeebled, in fact ahnost obsolete, on the last turn. These 

 riblets are distantly spaced on the early turns, but they become more 



