1897.] NATURAL SCIENCES OF PHILADELPHIA. 503 



DESCRIPTIONS OF TWO NEW FORMS OF PERIDERIS. 

 BY HENRY A. PILSBRY. 



Perideris Kobelti n. sp. 



Shell ovate, ventricose, whitish under an olivaceous yellow cuti- 

 cle, brownish in places. Surface obliquely plicatulate in the direc- 

 tion of growth lines, and above the periphery decussated by numer- 

 ous rather inconspicuous spiral impressed lines. Spire abruptly 

 contracted above, mucronate. Whorls about 6J, the earlier 1\ 

 forming a mamillar projection, the rest rapidly widening, last whorl 

 swollen. Suture white from loss of cuticle, and minutely beaded. 

 Aperture oblique, reddish inside; lip obtuse, brown; columella 

 whitish, vertical rather straight, subtruncate below. Alt. 65, diam. 

 40, alt. of aperture 35 mm. 



Cape Palmas, West Africa. Type in coll. A. N. S. P. 



This species is evidently identical with Kobelt's P. saulcydi 

 (Conchyl. Cab., p. 42, pi. 13, f. 1, 2). It is far from being the species 

 so called by Joaunis. It is likely that Kobelt had not seen Joannis' 

 original description and figure, from the fact that his reference to 

 that author is altogether incorrect ; and thus the misidentification 

 arose. 

 Perideris Saulcydi var. normalis n. var. 



Shell resembling Achatina Saulcydi Joannis (Magazin de Zoolo- 

 gie, 1834, Classe V, pi. 50) in the general coloration, being white 

 streaked with livid purple, with some bluish suffusion, the pen- 

 ultimate whorl whitish with reddish flames. Whorls about 7$, the 

 earlier 3 forming a mamillar mucro, higher and more distinctly 

 differentiated than in Saulcydi, those following forming a more taper- 

 ing cone than in Saulcydi, the last not perceptibly constricted below 

 the suture. Suture margined below by a narrow crenate or beaded 

 band. Sculpture : unequally, obliquely plicatulate, sometimes with 

 subobsolete spirals on penultimate whorl, the hist whorl with faint, 

 obliquely descending, scar-like impressions at right angles to the 

 growth-lines. Aperture oblique, dark purplish-brown inside ; parie- 

 tal wall orange-brown from the retention of the cuticle by the parie- 



