168 PROCEEDINGS OP THE MALACOLOGICAL SOCIETY. 



Long. 28, lat. 9 mm. 



Hah. — Goree, West Africa ; collection Denans. 



This extremely select species was examined by tlie late Mr. G. B. 

 Sowerby, who wrote that at first he considered it might be an 

 albino variety of P. lineata} Lam., but that it was well distinguished 

 from that species by the " plicate angle ". It certainly seems 

 abundantly distinct from any other known Perrona. 



SURCULA MACILENTA, n.Sp. (PI. V, Fig. 13.) 



Shell fusiform, gracefully attenuate, thin, pale tan-coloured; 

 whorls 9-10, of which the two nuclear are pale, shining, and 

 globose ; the remainder medially angled, suturally impressed, 

 longitudinally ribbed ; ribs broad, rather irregular, rounded, oblique, 

 the whole surface crossed very delicately by close revolving sulculose 

 striae. Mouth oblong, sinus (in type specimen) hardly expressed, 

 but the shell may not have quite reached its full growth, the outer 

 lip being thin. Columella straight, canal abbreviate, wide. 



Long 17, lat. 5 mm. 



Hah. — South Africa. 



This appears nearly allied to D. lanceolata,^ Reeve, and likewise 

 to the much larger Surcula undatiruga,^ Biv., this being a 

 Mediterranean species, of which tenuis, Gray, is a synonym. 



(Macilenta, lean.) 



''' Mangelia inteecedens, n.sp. (PI. V, Fig. 14.) 



Shell fusiform, small, delicate, thin, white with partial pale yellow 

 sufEusion ; whorls 7, of which three are nuclear, globose, semi- 

 diaphanous, white, shining, the third being microscopically 

 longitudinally striate ; the remaining whorls, all impressed suturally, 

 are closely longitudinally ribbed ; these ribs are close, shining, and 

 smooth, obliquely flexuose, with the interstices finely spirally striate. 

 Mouth ovate-oblong, outer lip thin, but hardly adult, columellar 

 margin oblique, canal abbreviate. 



Long. 5, lat. 2 mm. 



Hah. — Cuba. 



A distinct species. Dr. Dall writes concerning it : " This belongs 

 to the group of cerina, Kurtz & Stimpson,* from the Atlantic shores 

 of U.S.A. Though worn, we cannot identify it by any species in 

 our collection." It may likewise be found comparable with another 

 West Indian species, viz. M. dorvillece, Gray.^ 



(Intercedens, a go between.) 



^ Reeve, Conch. Icon. Pleurotoma, 1843, pi. xi, figs. 96a, b. 



* Proc. Zool. Soc. Lond., 1845, p. 111. Also Reeve, Conch. Icon., i. 

 Pleurotoma, pi. xxi, fig. 182. 



3 PhU. MoU. Sicilije, ii, pi. xxvi, fig. 13. 



* Proc. Boston Nat. Hist. Soc, iv, p. 115. 



^ Reeve, Conch. Icon., i. Pleurotoma, pi. xxviii, fig. 249. 



