138 PHASTS-TRACHYCYSTIS. 



periphery. Aperture subquadrate ; peristome simple, a little reflexed 

 at the columellar margin. 



Alt. 2-25 diam. 3 mill. (M. & P.) 



Bredasdorp, in sand under stones, and Cape Point, S. Africa. 



Helix (Pella) erateina M. & P., Ann. Mag. N. H. (6), ix, p. 88, t. 

 5, f. 3. 



A most elegant and beautiful little shell, found, as noticed above r 

 by Mr. Layard in two localities ; we have taken the Bredasdorp 

 specimen as the type. Though minute, the sculpture is most elabor- 

 ate, with fine oblique lirube extending over the entire surface. The 

 umbilicus is deep, though narrow, last whorl serrately keeled, aper- 

 ture somewhat square, lip simple. (M. & P.) 



This species should be carefully compared with the H. prionacis 

 and If. browningii of Benson, both of which are very closely allied. 



P. LYG^A Melvill & Ponsonby. PL 35, fig. 7. 



Shell profoundly but narrowly umbilicated, horny, thin ; spire 

 depressed-conoid ; whorls 6, the last acutely carinated, closely and 

 regularly obliquely striated above and below ; aperture lunar ; per- 

 istome simple, reflexed at the base, and forming a triangular lamina 

 at the columella. Alt. 7, diam. 12 mill. (M. & P.) 



Natal (Lightfoot.) 



Helix (Pella) lygcea M. & P., Ann. Mag. N. H. (6), ix, p. 85, t. 4, 

 f. 7 (Jan., 1892.) 



A conspicuous species, but one which we have not seen in good 

 live condition. It is of the same horny and striated character of 

 whorl as the last two species, much resembling H. lens Fer. in 

 miniature, but the outer lip is not so strongly expanded nor devel- 

 oped as in that species. (M. & P.) 



Group of H. bisculpta. 



P. AULACOPHORA Ancey. PL 43, figs. 60, 61. 



Shell narrowly umbilicated, globose-depressed, rather thin, pale 

 horny-brown colored, lusterless. Spire low-conoidal, apex obtuse ; 

 sutures well impressed. Whorls 41, convex, the first smooth, the 

 rest closely plicate-striate, slowly increasing ; the last whorl very 

 convex beneath, and having the cuticular folds more delicate and 

 crowded on its latter portion ; on the base these riblets are radiating ; 

 on the upper surface they bend obliquely backward, and make a 



