PROCEEUINGS 



UNITED STATES NATIONAL MUSEUM 



mOR T^HE YEAR 1890. 



Volume XIII. 



DESCRIPTION OF A NEW SPECIES OF LAND SHELL FROM CUBA- 

 VERTIGO CUBANA. 



Wm. H. Ball, . 



Curat 07- of the Depatment of MoUusks. 

 Vertigo cubana sp. nov. 



Testa parva, dextrorsa, rubesceiite castanea, apice pallida, obtusa-, 

 aufr. V convexi, superficies spiraliter striatula, costulis trausversis flex- 

 uosis ad XXV, couciune clathrati ; basis imperforata ; apertura caoipa- 

 iiulata, tiilobata, obliqua; singulis dentibus in margine dextro et iu 

 basali, duobus in pariete aperturali; max alt. .07; max. lat. .055 poll. 



Shell pinkish brown, paler toward the apex, small, short, stout, dextral, 

 five-whorled; apex rather bluntly rounded, sides subparallel, base full 

 and rounded ; spiral sculpture of fine strife, most prominent betweeu 

 the ribs on the last whorl and obsolete on the early whorls ; they do no( 

 overrun the ribs; transverse sculpture of (on the last whorl about; 

 twenty- five) strong, sigmoid, squarish, narrow, elevated ribs, running 

 from suture to suture, and separated by much wider interspaces; 

 these ribs are closer and finer toward the apex of the spire^ they re- 

 semble when best developed those of Fu^a lyraia Gould ; last whorl 

 subconstricted before the aperture is formed ; aperture obscurely trilo- 

 bate, margin well reflected, whitish ; primary lamellse, except A and E, 

 set rather more deeply in the throat than usual. Formula j?l E ac- 

 cording to Dr. Sterki's arrangement. The primary A is stronger and 

 more triangular at the aperture than the others, but becomes a thin, 

 narrow, sharp lamella internally; the secondary, 2, does not come sg 

 near the aperture as A, but further back is a little higher tha?). thelat- 



Proceedings Nalioual Museum, Vo] XIll--A^a 7S0. 



Proc. N. M. 90 1 



