GASTROCOPTA. 203 



but does 11 ot emerge far. Its inner end turns down on the 

 columellar axis, the whole tooth having the shape of an in- 

 verted L or the figure 7. The vertical or axial portion tapers 

 downwards, and is fully seen only in an oblique view in the 

 mouth, though the degree of immersion varies rather widely 

 in different lots. The upper-palatal and the basal folds are 

 short but well developed, usually brown-tinted. The lower- 

 palatal fold is long, reaching to a subdorsal position. Its 

 outer half is brownish, the inner half is higher, white and 

 strongly curved. The peristome is brown, reflected, thickened 

 within more or less. The parietal callus is moderately thick 

 and very short. Dimensions variable ; usually between : 



Length 2 mm., diam. above aperture 0.8 mm. ; 4% whorls. 



Fig. 1. Length 2.4 mm., diam. above aperture 0.8 mm. ; 

 5y 2 whorls. 



Fig. da. Length 1.85 mm., diam. above aperture 0.75 mm. ; 

 4!/o whorls. 



Fig. 3. Length 2.2 mm., diam. above aperture 0.95 mm. ; 

 5 whorls. 



Dutch West Indies: Aruba, Curasao, Bonaire and Klein 

 Bonaire (H. Burrington Baker) ; type 133584 ANSP. from 

 Fort Nassau, Willemstad, Curasao. 



Pupa longurio Crosse, Journ. de Conchyl., xx, 1872, p. 158; 

 xxi, 1873, p. 42, pi. 1, fig. 2. Not Pupa longurio Moquin- 

 Tandon, Hist. Nat. Moll. France, ii, 1855, p. 379 (=P. affinis 

 Rossm.) . — Gastrocopta longurio (Crosse) Pilsbry, Man. Conch, 

 xxiv, p. 82, translation of original desc. — Gastrocopta cura- 

 coana Pilsbry, Proc. A. N. S. Phila., lxxvi, 1924, p. 62, text- 

 figs. l-4a. 



This variable species is related to G. barbadensis, but it is 

 certainly distinct by the decidedly longer lower-palatal fold, 

 its inner half curved downward, by various small differences 

 in the lamella?, and by the long, slim shape and strongly con- 

 vex whorls, the last one more compressed laterally. 



The slender shape, which Crosse noted in his description 

 of P. longurio, is not invariable ; and indeed, the shape some- 

 times varies notably in one colony, as in the case of the shells 

 from Bonaire drawn in figures 3, 3a. The details of shape 

 and degree of immersion of the columellar lamella also vary. 



