178 MAZATLAN UXIYALVES 



Tablet 811 contains a sketch of a solitary specimen which 

 was found by Mr. Archer amoag the small shells. It was 

 referred by Mr. Cuming to Bulinus Broderipii, Sow. in Proc. 

 Zool. Soc. 1832: Conck. III. f. 1. ( = Plectostylus Broderipii, 

 H. fy A. Ad. Gen. ii. 155 :) but as it does not accord with the 

 figures of that Chilian species, it was perhaps an oversight. 

 Lamarck's description might also serve for B. Ziegleri, which 

 this shell very greatly resembles. It is however more inflated 

 and thinner. Long. '65, long. spir. '35, lat. *4. 

 Hob. Mexico, Humboldt fy Bonpland- ? Mazatlan ; 1 sp. 



with B. Ziegleri ; L'pool Col. 



OEDEE LIMNOPHILA. 



FAMILY AUBICULIDyE. 



GENUS MELAMPUS, Montf. 



Melampus, Montf. Conck. Syst. 1810. 



Conovulus, Lam. 1812. This genus was afterwards suppressed 

 by its author, and united to Auricula. 



4 235. MELAMPUS OLIVACEUS, n. s. 



M. t. parvd, sublcevi, conoided, spird depressd, infra suturam 

 indistinctam obscure angulatd ; albidd, fusco-purpureo irregu- 

 lariter tessellatd, epidermide adkcerente olivaced indutd ; anfr. 

 vii. vix rnonstrantibus, planatis ; aperturd longd, angustd, ad 

 marginemfusco-purpured, intus albd ; labro ad marginem acuto, 

 intus dentato, dentibus in liras acutas, in adultd scepe obsoletas, 

 decurrentibus ; labio tenui, plied und parietali transversd, inter 

 denticulas duas sitd, in juniore denticulis mynerosis intus 

 conditis ; columelld plied und obliqud, ad basin excurrente ; 

 parietibus internis in adultd absorptis. 

 Melampus bidentatus, Moerch in Mus. Cum. : non Say. 



Moerch must surely have been in error in regarding this 

 species as a variety of M. bidentatus. It is much more nearly 

 allied to the Yoluta cofiea of Linn. The specimens, of which 

 many hundreds were sent, are very constant in the characters 

 above given ; of which the most distinguishing are the olive 

 green epidermis, with the irregular purplish brown tessellated 



