HELIX. 183 



The very depressed, lenticular form, convex base, conspicuous 

 but not compressed nor filiform carina, and smooth, regular cost a - 

 tions, readily separate this species from its allies. 



H. SAPONACEA Lowe, 1861. PI. 50, figs. 65-67. 



Covered perforate, orbiculate-depressed, solid, striate and densely 

 minutely granulate, shining, above yellowish corneous, narrowly 

 trifasciate with brown, smoother and paler below, umbilical tract 

 whitish, spire slightly convex, apex minute granulate, suture lightly 

 impressed; whorls 4i, rather slowly increasing, the last depressed, 

 obsoletely angulate at periphery, constricted and abruptly falling 

 anteriorly, somewhat convex below; aperture very oblique, sub- 

 quadrate-hmar, livid within; peristome heavily white-labiate, margins 

 subparallel, remote, hardly converging, basal margin straightened, 

 widely reflexed and adnate, covering the umilicus. 



Diam. 17-18, alt. 8-9 mill. 



Ins. Grand Canary. 



H. PSATHYRA Lowe, 1861. PL 50, fig. 79. 



Imperforate, depressed,, thin, fragile, obliquely striate, brown or 

 corneous-greenish, with four or five ill-defined brownish bands; spire 

 slightly elevated, apex obtuse, suture impressed, submarginate ; 

 whorls 5, rather flattened, regularly increasing, the embryonic 

 minutely granulate, the last with fine irregular incremental strise- 

 .and faint malleations, periphery obsoletely angulate, anteriorly sub- 

 inflated and profoundly deflexed ; aperture very oblique, subdeltoid- 

 oval ; peristome thin, fragile, broadly expanded, the margins sub- 

 -converging, basal reflexed, rather straightened, dilated at the inser- 

 tion, and broadly adnate above the axial region. 



Diam. 22-24, alt. 12-14 mill. 



I)is. Grand Canary. 



H. THESPESIA Mabille, 1882, PI. 48, figs. 19, 20. 



Imperforate, depressed-suborbiculate, thin, a little shining, under 

 a lens broadly costulate-striate and irregularly crispate-malleate, 

 corneous-reddish or greenish; spire subdepressed, apex subacute, 

 -obscurely punctulate, reddish; whorls 4-5, slightly convex, sub- 

 regularly, rapidly increasing, suture impressed, obscurely albo- 

 inarginate; body-whorl at its origin angulate-rounded, becoming 

 rotund, slightly descending, a little inflated beneath; aperture 

 oblique, lunate, transversely oblong-ovate, margins subdistant ; peri- 

 stome acute, briefly reflexed, thickened with white within, margins 



