PHASIS-TRACHYCYSTIS. 137 



Whorls 4 2, slightly convex, slowly increasing, the last rather 

 obtusely keeled at the periphery, compressed just below the keel. 

 Aperture but little oblique, rhomboidal ; peristome thin, strongly 

 curved at the outer part and where it joins the columella ; colu- 

 mellar lip dilated above. Alt. 83, diam. 5 mill. 



kCape Point, South Africa. 

 Helix browningii BENS., Ann. & Mag. N. H. (3) xiii, p. 493. 

 FR., Mon. v, p. 178. 



The specimen described above and figured on my plate is from 

 the original locality. H. erateina Melv. & Pons. should be com- 

 pared, but it differs in the somewhat more compressed keel and 

 smaller size. 



Benson says that this species is smaller than H. prionacis, with 

 the same number of whorls ; the plication is closer, less deep, and 

 more regular, and extends only just below the angulate periphery, 

 instead of to the umbilicus, which is wider in prionacis. In the lat- 

 ter species the periphery is more compressed, the rufous-brown 

 markings are more disposed to be spotted than strigate, and do not 

 extend to the lower side as in H. browningii. 



P. PRIONACIS Benson. Unfigured. 



Shell umbilicated, conoid-depressed, above and below strongly 

 obliquely plicate, the plicae remote, whitish ; whitish-horny, here and 

 there ornamented with brown spots. Spire conoid, suture impressed, 

 apex slightly obtuse. Whorls 5, slightly convex, narrow, the last 

 compressedly carinated, convex below. Aperture wide lunate, ax- 

 shaped ; peristome thin, acute, columellar margin expanded, dilated 

 above. Alt. 3, greater diam. 6, lesser 5 mill. (Bens.} 



Bredasdorp, South Africa. 



Helix prionacis BENS., Ann. Mag. N". H. (3), xiii, p. 493, 1864. 

 PFR., Mon. v, p. 183. 



See notes under H. browningii. 



P. ERATEINA Melvill & Ponsonby. PL 35, fig. 11. 



Shell deeply but narrowly umbilicated, lenticular, depressed-conic. 

 Whorls 5, ashy, begirt obliquely with close regular lamellose riblets, 

 and decorated with longitudinal rufous flammules; having a cren- 

 ulated appearance at the sutures ; last whorl serrate-carinate at the 



