PLANORBIS. 



123 



Hah. Near Mexico, with P. inuiis, wliicli is, however, a rarer species: 

 David & Ilerr Geb. M. R. Dr. N. Meyer. (Kuster.) 



Planorbis frac/ilis, Ddxker in Ch. ed. 2, p. 46, pi. viii, f. 41^3. 



I have given above a copy of the description and figure of this 

 species. 



Plaiiorliis lautiis, H. Adams. — Shell subovate, thin, the height 

 equalling the width, yellowish-white, deeply and narrowly nmbilicated 

 above, flat below ; whirls three, rapidly increasing, rounded, angulated 

 and contracted above, carinated below, decussated by fine striae ; aperture 

 slightly oblique, subovate, extending above the penultimate whirl, peri- 

 treme continuous. Diam. 2 lin. 



Hal). New Orleans. (H. Adams.) 



P/uiiorbi.f (Helisoiiiu) lantus, H. Adams, Proc. Zool. Soc. Loudon, 1861, 

 p. 145. 



I have not seen this species, of which the original description 

 is given above. 



Plaiiorl>is toicarinatlis, Say. — Shell sinistral, pale yellow or 

 brownish, subcarinate above, and beneath translucent. Spire retus-um- 

 bilicate, forming a cavity as deep as that 

 of the base. Aperture large, embracing 

 a considerable portion of the body whirl, 

 and much vaulted above. Within red 

 brown, with two white lines corresponding 

 with the carina. Whirls three, wrinkled 

 and with minute revolving lines. Length 

 one-fourih of an inch, breadth nearly 

 half an inch. • 



Inhabitant aquatic, ferruginous, with 

 numerous yellowish dots ; tentacula dot- 

 ted and flexuous. PI. 1, fig. 4. Resembles 

 the preceding species in its outline, but differs from that shell in the re- 

 markable appearance of its spire ; it is also destitute of those fine parallel 

 raised lines, and is furnished with minute striae, never visible in P. iri- 

 volvis ; the superior part of the lip is more vaulted, and the carina more 

 visible. (^Suy.) 



Planorhis hicarinatus. Say, Nich. Ency. pi. i, f. 4 (1817, 1818, 1819) ; Am. 

 Couch. 6, pi. liv, f. 3 (1834): Binney's ed. 44, pi. liv, f. 3; pi. 

 Ixix, f. 4. — Mrs. Gray^ Fig. Moll. An. pi. cccx, f. 1. — Haldemax, 

 Mon. vii, p. 6, pi. i, f. 1-6 (1844).— Adams, Shells of Vt. 155 (1842). 

 — DeKay, N. Y. Moll. CO, pi. iv, f. 63 (1843).— Gould, Inv. of Mass. 

 203, f. 134 (1841).— Chemn. ed. 2, p. 56, pi. Ix, f. 11-13.— Potiez et 

 MiCHADD, Gal. des Moll. I, 207, pl. xxi, f. 1-3.— Axon. Can. Nat. 

 II, 204, fig. (1857). 



Fig. 205. 



