ODONTOSTO.MUS. 51 



species by the thickening of the suture and the arrangement of teeth ; 

 the latter resembling those of 0. rinyens, which is apparently the 

 most nearly allied species. 



Group of 0. janeirensis. 



Aperture oval or oblong, the outer lip arcuate ; a columellar fold 

 or lamella developed, with sometimes a small basal fold and parietal 

 lamella; no palatal folds. Surface usually rather rough, pitted, 

 malleale, wrinkled or costulate. Species allied to 0. punclatissitnus, 

 in which the folds or the. folds tmd hum- 11 re have degenerated, leav- 

 ing a toothless or almost toothless aperture. Only janeirensis, inilinlti 

 and neglectus are known to me by specimens. The former two have 

 typical Drymceus apical sculpture, but in neglectus the vertical ribs 

 predominate and are rather coarse. It may belong to Spixia (q. v.) 

 rather than to the present group. 



Possibly '' Gonyostomus centiquadrus Valenc." of Beck, Index p. 

 53 (Paraguay), may be something of this nature ; but it is merely a, 

 name, never made good by description. 



0. RHODINOSTOMA (Orbigny). PI. 9, figs. 14, 15. 



Shell elongate, turreted, umbilicate, a little rugose, somewhat 

 glossy ; grayish-white, with longitudinal brown lines ; the peristome 

 and columella rose, and with a large brown spot within the lip. Spire 

 long, swollen for the. greater part of its length, the apex obtuse ; 

 composed of 8 slightly convex whorls, the last very large, separated 

 by a smooth suture, but little impressed. Aperture small, oval, with 

 thin, acute \ eristome a little reflexed ; columella wide, noticeably 

 swollen. Length 21, diani. 7 mill. (0r&.). 



Brazil : obtained by M. Fontaine at Rio Janeiro. 



Helix rhodinostama OKI;., Mag. de Zool., 1835, p. 20. Jiulimus 

 rhddinpstoma ORB., Voyage, p. 317, pi. 41, f. 68. PFR., JMonogr. 

 ii, p. 90 ; iv, 407 Odontostomus rhodostoma H. & A. ADAMS, Gen. 

 Rec. Moll, ii, p. 152. 



Very close to the typical form of 0. janeirensis, with which it may 

 be identical. 



O. JANKIRE.VSIS (Sowerby). PI. 10, figs. 22, 23, :>4. 



Shell rimate, fusiform-turreted. thin but moderately strong, longi- 

 tudinally streaked with opaque cream-white over ground of a pale 



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