142 OXYSTVI.A, SOUTH AMKKH AN. 



STKKBKI.. P>eitr. Mex. Land- und Siisswasser-Conch. v, p. 42, pi. 6, 

 f. 2 n-c. 



The obtusely angulated periphery of the last whorl and distinct 

 spiral stria: seem to distinguish this form from those varieties of 0. 

 maracaibensis which have a similar " griseo-fulvescens " color, nar- 

 row varict-s with clear light border, and three hands or none. The 

 words '* obsoletely clouded with bluish " of Pfeiller's diagnosis should 

 be deleted, as that appearance is due to the dried soft parts, accord- 

 ing to Strebel. 



A young specimen with the type in Dohrn's collection has three 

 faint but distinct spiral bands. Strebel's specimens were received 

 with shells from the Ilacha river, and in all probability came from 

 that place. The smaller one shows some faint longitudinal streaks 

 on the third and fourth whorls, which puss into spots and then disap- 

 pear farther on. The larger (fig. 48) shows a narrow peripheral 

 band of light chestnut right above the suture on the fourth and tilth 

 whorls, fading and changing to a whitish band on the last whorl ; the 

 upper band appears on the fourth whorl, is white, and continues, 

 though indistinct, to the aperture. The white part of the bands is 

 more tran.-parent than the rest of the shell. 



0. iSAi'.K.i.i.iNA (von Martens). PI. 31, fig. GG. 



Shell ovate-conic, rather thin, very lightly striatulate, plicatulate 

 at the suture, sculptured with very close, fine spiral lines ; isabelline, 

 \\itli pale, blackish streaks and three narrow brown bands, generally 

 frequently interrupted, and with a tew brownish varices. Spire conic, 

 tin- apex In-own or white; whorls nearly <">, a little convex, the last 

 moderately swollen. Aperture rather oblique, a little exceeding half 

 the .-hell's length, rhombic-Oval, brownish and variegated with chest- 

 nut inside; eoluniella straight, thin, white; peristome unexpanded, 

 acute, isabelline or pale brownish; no parietal callus. 



Alt. I'.', diam. 2:51, length of aperture 21.',, width I. 1 ! mill. (J//.v.) 



Peru, forests of the cusii-i-it */<>/>c oj the inland cordillcm (Tschudi). 



Hitliniiis zebra var. * Ti;os< in i , Archiv I'm- Naturgeschichte 1S.V2, 



1, p. IK.'i. (Irt/iuf/ri/s isdln-lliiniK von MAKTKNS, Blimenmoll. Vene- 

 zuela's, in Festschrift (Jes. Naturforvh. Freunde Berlin, p. 1 ill, pi. 

 1, f. H C1H7,'3). Pi K., Monogr. llel. Viv. viii, p. 2C,;5. 



Apparently belongs to the group of 0. ferussaci. Dr. von Martens 

 figures a smaller specimen than his measurements indicate as the size 



