STROPHOCHEILUS. 9 



face under a lens showing very minute and close, finely beaded spiral 

 strice throughout. Whorls 5, the first planorboid with sunken tip, 

 forming an obtuse apex ; last whorl obliquely descending. 



Aperture about half the shell's length, somewhat oblique, purplish 

 within ; peristome reflexed, recurved, deep rose colored, broad and 

 spreading below ; columella expanded above, its inner edge straight 

 and oblique; parietal callus bluish. Alt. 57, diam. 31 ; alt. of aper- 

 ture 29 mill. 



Brazil. 



Bulinus milleri SOWB., Conch. Illustr. f. 94. Bit limits mllleri 

 EEEVE, Conch. Syst. ii, pi. 174. f. 94 ; Conch. Icon., pi. 28, f. 169.- 

 PFR., Symbolse, ii, p. 48 ; Monogr. ii, p. 25 ; vi, p. 12. 



The granulose stride and satin zones of the surface distinguish this 

 from S. planidens, aside from the tooth and differently formed col- 

 umella of the latter. 



S. UNIDENTATUS Sowerby. PI. 22, fig. 56. 



Shell imperforate or nearly so, ovate, swollen, solid and strong; 

 part roseate, part white, under a yellowish-brown cuticle. Surface 

 having inconspicuous growth-lines, a shallow malleation, and dense 

 microscopic spiral striation. Whorls nearly 5, the first planorboid, 

 the last obliquely descending, large and oval. 



Aperture somewhat oblique, small, somewhat over half the total 

 length, white inside ; peristome reflexed and recurved, dark brown 

 throughout, the outer lip bearing a whitish tooth-like nodule in the 

 middle. Columella narrow, hardly wider above, foldless ; and 

 together with the rather heavy parietal callus, dark brown through- 

 out. Alt. 53, diam. 32 mill. ; aperture measured outside peristome, 

 alt, 29, width 20* mill. 



La Plata valley (coll. A. N.S.P.) ; Jimzif (Pfr.). 



Partula unidentata SOWB. inCatal. Tank, coll., appendix, p. vii. 

 GRAY, Ann. of Philos. (n. s.) ix, p. 415. Bulimus wiidentalus BECK, 

 Index, p. 53. PFR., Symb. iii, 88 ; Monogr. ii, p. 54. DESK, in 

 Fer., Hist, p. 99, pi. 143, f. 6. PHII.., Abbild. iii, p. 99, pi. 9, f. 8.- 

 REEVE, Conch. Icon. pi. 31, f. 192. 



A rare species. The sculpture is like 8. erythrosoma, differing 

 from planidens in being malleated. The tooth of outer lip, brown 

 peristome and obese form readily distinguish the species. 



