390 PROCEEDINGS OF THE NATIONAL MUSEUM vol. 85 



The type, U.S.N.M. no. 367757, comes from Potrero Fiimero, Vieja 

 Bermeja. It has 4 whorls remaining and measures: Length, 14.0 

 mm ; greater diameter, 10.8 mm ; lesser diameter, 7.4 mm. 



GUTIERREZIUM, new subgenus 



Shell turbinate. Nuclear whorls, 1.8, well rounded, microscopic- 

 ally granulose. Postnuclear whorls inflated, strongly rounded, and 

 marked by slender axial ribs and spiral threads, which vary in 

 strength from that equal to the axial ribs to almost obsolete in differ- 

 ent species. The junctions of the axial and spiral sculpture form 

 pronounced tubercles. On the last whorl the sculpture usually be- 

 comes almost obsolete. Periphery strongly rounded. Base inflated, 

 strongly rounded, and marked by the continuation of the fine axial 

 riblets and spiral threads a little stronger than those on the spire 

 of the last turn. These form cords in the rather widely open um- 

 bilicus. Aperture broadly ovate; peristome double, the outer very 

 broadly expanded excepting on the parietal wall where it is nar- 

 rower; the inner slight!}^ projecting and reflected partly over the 

 outer. Operculum thin, corneous, paucispiral with subcentral nu- 

 cleus. 



Type: Chondropoma {Guticrrezium) hai/e)ise, new species. 



This subgenus is closely allied to Chondropomella Bartsch of 

 Santo Domingo, which is typified by Chotulropom,a {Chondropo- 

 mella) magnifica (Salle) Pfeiffer. Here, however, we have the 

 sjiiral sculpture extending upon the whorls between the periphery 

 and summit of the turns, which is not the case in Chondropomella. 

 In some of the species this sculpture is quite reduced and requires to 

 be looked for sharply not to be overlooked. 



KEY TO THE SPECIES OF SUBGENUS GUTIERREZIUM 



Suture channeled. 



Spiral sculpture strong bairense 



Spiral sculpture feeble canaliculatum 



Suture not channeled. 



Axial ribs closely spaced. 



Outer peristoiue very broadly expanded montanum 



Outer peristome only moderately expanded guisaense 



Axial ribs distantly spaced gutierrezi 



CHONDROPOMA (GUTIERREZIUM) BAIRENSE, new species 



Plate 38, Figure 2 



Shell broadly ovate, turbinate; the early whorls chestnut-brown, 

 the succeeding turns flesh-color, marked by almost conspicuous inter- 

 rupted spiral bands of brown, of which four are present on the spire 

 and four on the base. They also mark the outer peristome and the 



