FERUSSACIA, SECTION PEGEA. 241 



glossy, pale-corneous, very sharply substriatulate or somewhat 

 polished; spire moderately produced, at the summit rather 

 abruptly attenuate, the apex obtuse; whorls 7, slightly con- 

 vex, somewhat irregularly increasing, the upper whorls slowly, 

 the rest rapidly ; separated by a linear and paler suture ; last 

 whorl rather large, not half the total length, a little convex. 

 Aperture oblique, receding at the base, rather lunate, irregu- 

 larly oblong, angular above, outwardly subarcuate, having a 

 lamella within on the parietal wall. Oolumella strong, 

 straightly descending, acute below, calloused and quasi sub- 

 denticulate above ; peristome unexpanded, obtuse, a little 

 thickened, the outer margin arcuate and produced above, re- 

 ceding at the base ; margins joined by 'a strong callus. Length 

 11, diam. 3, aperture 5 mm. (Bgt.). 



Tunis: Medjerda R. at the bridge of Fondouck between 

 Tunis and Utique (Bgt.). 



Ferussacia splendens BGT., Prodr. Malac. Tunisie p. 117, 

 1887. 



''In shape this species resembles F. aphelina a little." 



23. F. OBESA Letourneux et Bourguignat. 



Shell tumid-oblong, obese, very glossy, pale corneous, with 

 a white thread at the suture, polished ; spire moderately pro- 

 duced, quite rapidly tapering at the summit, the taper regu- 

 lar, apex stout, obtuse; whorls 6, a trifle convex, regularly 

 increasing to the penultimate, then rapidly increasing, the 

 penult, suture relatively quite rapidly descending; suture 

 linear ; last whorl relatively of medium size, slightly over one- 

 third the total length, a little convex. Aperture suboblique, 

 piriform, very angular above, with a lamella, which is minute, 

 deeply immersed, reaching inward on the belly of the penult, 

 whorl. Oolumella short, little thickened, straightly descend- 

 ing in an oblique direction towards the right ; peristome unex- 

 panded, obtuse, whitish, continued in a strong parietal callus ; 

 outer margin subobliquely straightly descending. Length 12, 

 diam. 4, aperture 4.5 mm. (L. & B.). 



Tunis: Djebel Resas (Letourneux). 



Ferussacia obesa, L. et B., Prodr. Malac. Tunisie p. 118. 



Like F. gronoviana in shape. 



