144 STREPTOSTYLA. 



last whorl they are wholly wanting or persist weakly just 

 below the suture, the surface being weakly striatulate and 

 marked with a few growth-arrest grooves. 



Length 24.8, diam. 8, aperture 13 mm. ; -whorls 9. 



Length 21, diam. 7.2, aperture 12 mm.; whorls Sy 2 . 



Length 23, diam. 8 mm. (Morelet). 



Western Cuba : Rangel, and the whole Organ Mountains 

 (Arango). 



Glandina episcopalis MOREL., Testacea Novissima, i, p. 13 

 (1849). Streptostyla e., ARANGO, Fauna Malac. Cubana, 

 p. 98. 



Genus STREPTOSTYLA Shuttleworth. 



Streptostyla SHUTTL., Mittheil. nat. Ges. Bern, 1852, p. 203. 

 v. MARTS, in Albers, Die Hel., 1860, p. 33, type 8. nicoleti; 

 Biologia Centrali Americana, Moll., p. 83. STREBEL, Beitrag, 

 etc., iii, pp. 5, 11, 1878. 



Shell oblong, varying from cylindric to biconic, with piri- 

 f orm or lanceolate, usually long and narrow aperture ; outer 

 lip arching forward in the middle. Columella strongly 

 twisted spirally, bearing an entering callous lamella, passing 

 in a broad curve into the basal lip. Animal externally as in 

 Euglandina. Radula oleacinoid. 



Type 8. nicoleti Shuttl. Distribution, Mexico and Central 

 America (one species in Venezuela?). 



Streptostyla is akin to Oleacina in the general appearance 

 and texture of the shell, rather than to Euglandina. The 

 usually strong twist of the axis, with a callous cord superposed 

 on its free edge, and the nearly complete obliteration of the 

 basal truncation chiefly distinguish it. At the end of the 

 callus a weak trace of the columellar truncation is generally 

 visible. Spiraxis has undergone a similar modification of the 

 columellar axis, and some forms of Varicella approach the 

 same structure. In a few species, such as 8. lattrei, there are 

 some very weak varix-lines, preceded by dark streaks, as in 

 certain forms of Euglandina and Spiraxis, but much less de- 

 veloped than is the rule in Varicella. 



By the deposit of shell material internally in the crevice 



