152 STEEPTOSTYLA. 



This very briefly described form differs from 8. viridula 

 Angas by its slightly more lengthened contour and compara- 

 tively shorter aperture. 



21. S. DELIBUTA (Morelet). PI. 29, fig. 77, 78, 80. 



Shell cylindrical, thin, very minutely striate, glossy, semi- 

 diaphanous, corneous-green. Spire conoidal, short, the apex 

 rather obtuse ; suture slightly impressed, margined. Whorls 

 7, flattened, the last longer than the spire. Columella callous, 

 twisted, outwardly subtruncate. Aperture narrow, dilated 

 basally, pearly within. Peristome simple, the outer margin 

 dilated in the middle. Length 23, diam. 10 mm. (Morel.). 



Guatemala : Vera Paz (Morelet) ; environs of Yzabal 

 (Stoll) ; Alta Vera Paz (v. Ihering). 



Glandina delibuta MOREL., Testae. Noviss., ii, p. 13 (1851). 

 Streptostyla d., MARTENS, Biologia, p. 97, pi. 5, f. 18, 180. 



"The suture becomes very obliquely descending and dis- 

 tinctly margined (accompanied by an impressed line) in the 

 last whorl, but much less so in the preceding ones. The spire 

 is a little concavely attenuated at about the third whorl, 

 though on the whole rather broad and obtuse at the apex" 

 (Martens). 



The type figures are copied from von Martens, figs. 77, 78. 

 Under a strong lens faint, fine spiral lines are visible, as 

 shown in the detail figure. This is a rare feature in Strepto- 

 styla; however, on some specimens it is very difficult to make 

 them out, and only in a few places. The outer lip is rather 

 strongly arched forward, as shown in fig. 80, which repre- 

 sents the slenderest of several specimens before me. The col- 

 umellar callus in some shells forms a decidedly more project- 

 ing fold than in Morelet 's type. The shell is quite solid, with 

 a very thin pale yellowish-green cuticle, the interior fleshy- 

 white. Specimens measure: 23.7x10.25, apert. 15 mm.; 22 x 

 9.3, apert. 14 mm.; 23.7x10.7, apert. 15.3 mm. 



22. S. CRASSA Strebel. Vol. I, p. 47. 

 Distinct from delibuta by its wider contour. 



