168 POTAMIDES, CERITHIOPSIS. 



L. septevistriata, Say, usually applied to specimens with white 

 sutural baud, L. nigrescens, Menke, for the uniformly dark colored 

 specimens, L. nigrinum, Phil., being identical, L. clathrata, Menke, 

 Tj. heterodytes, Lam., L. striatella, Dillw., L. albovittata, C. B. Ad., 

 L. Peloriiana, Cantraine, L. laevigata, Phil. (= desolata, Bayle), 

 probably a worn specimen. Cerithinm Brongniarti, Marav. (C 

 Piraini, Benoit, and C. Hymerensis, Calcara, are said to be syno- 

 nyms), has been referred here by some European authors ; others 

 have considered it a distinct species allied to C. vidgatum; its iden- 

 tification remains doubtful. 



L. CORNEUM, Kiener. PI. 35, fig. 19. 



Thin, translucent, with rounded whorls and narrow longitudinal 

 plications, spirally striate ; reddish brown. Length, 10 mill. 



Hah. unknown. 



I know nothing about this species ; it seems to have escaped sub- 

 sequent monographers. It is scarcely a member of the present 

 group. 



Genus CERITHIOPSIS, Forbes and Hanley, 1853. 



C. TUBERCULARis, Montg. PI. 35, figs. 20, 22-25, 27. 



Apicial whorls smooth, the apex somewhat styliform ; normal 

 whorls with three spiral rows of regular, rounded tubercles, peri- 

 phery of last whorl angular, marked by a thread, base flattened, a 

 little concave ; chocolate brown. Length, ^'b mill. 



Europe, Madeira, W. Africa, W. Coast of N. America. 



The synonymy includes C. pidchella, Jeffreys (fig. 23), C. Henhel- 

 insii, Nyst, C. Clarkii, Hanley (fig. 25). 



Var. AcicuLA, Brusina. 



Form very narrow, elongated. 



C. nana, C. Barleei (fig. 27), and C. acieida, Jeffreys, are 

 synonyms. 



Var. ALBA, JeflTreys. 

 Shell white. 



Var. OBESULA, B; D. D. 



Shell smaller, form pupoidal. 



Var. BiLiNEATA, Hoemes. Fig. 24. 



Shell with two rows of tubercles on each whorl. 



C Barleei, Tiberi, C. ventricosa, Brusina, C. Coj)poloe, Aradas, 

 are synonyms. 



