OTOSTOMUS. 209 
All authors describe the aperture of this species as having a simple (not reflected) 
edge, but I can see in some specimens a very faint, but distinct, expansion of the edge 
outwards: in one of the examples collected by Mr. H. H. Smith it is quite strong and 
2 millim. broad. The interior of the aperture is described as chocolate-coloured: in 
the specimens collected by Uhde it is of a greyish rose-colour, in those by Mr. H. H. 
Smith either rose-coloured or pure white; the columella is in all of them white. 
The largest specimens, long. 44 millim., unicolorous, white, are from the summit of 
the Sierra de las Aguas Escondidas, 9500 feet, near Omilteme, in the State of Guerrero, 
collected by Mr. H. H. Smith. 
13. Otostomus rudis. 
Bulimus rudis, Anton, Verz. d. Conch. Samml. p. 43 (1839)'; Pfr. Symb. Hist. Helic. ii. p. 50°; 
Monogr. Helic. Vivent. ii. p. 197°; Reeve, Conch. Icon. v., Bulimus, t. 44. fig. 2864. 
Bulimus (Mesembrinus) rudis, Albers, Die Helic. ed. 1, p. 157°; Pfr. in Malak. Blatt. ii, p. 158 
- (1855) °. 
Orthalicus (Mesembrinus) rudis, H. & A. Adams, Gen. Moll. ii. p. 157". 
Bulimulus (Scutalus) rudis, Fisch. & Crosse, Miss. Scient. Mex., Mollusca, i. p. 528, t. 23. figg. 6, 6 a, 
t. 22. figg. 7-11 (jaw, radula, anatomy) °*. : 
Bulimulus rudis, Strebel, Beitr. Mex. Land- und Siissw.-Conch. v. p. 63, t. 5. fig. 3, t. 6. fig. 9°. 
Otostomus (Scutalus) rudis, v. Mart. Conch. Mittheil. ii. p. 193°. 
Bulimulus sulcosus, form A, Strebel, Beitr. Mex. Land- und Siissw.-Conch. v. p. 61, t. 5. figg. 1, 2, 
t. 11. figg. 12a, 6, 13, 14, 15, t. 13. fig. 8 (radula) ”. 
Bulimulus (Scutalus) sulcosus, var. B. fenestratus, v. Mart. in Malak. Blatt. xii. p. 34 (1865) . 
Hab. CentraL Mexico: environs of the city of Mexico (Hahn ® 1!) ; Chapultepec (Hege- 
wisch?*); Angangueo, State of Michoacan (Deppe " 1”). 
Mexico, without nearer indication of locality (Uhde! 1”). 
O. rudis is very closely allied to O. sudcosus: the stripes are more numerous and 
distinct, the general form is more ventricose, the sculpture is, perhaps, a little less 
strong; and the interior of the aperture is pale yellowish, the outside stripes showing 
through. The specimen figured by Strebel +" (t. 6. fig. 17) forms an intermediate link 
between them. 
The habitat “ Central America” given by Mérch, based on a young specimen, and 
brought forward with some doubt [Malak. Blatt. vi. p. 112 (1860)], is too indefinite 
to be admitted. 
14. Otostomus ghiesbreghti. (Tab. XIII. figg. 5-10). 
Bulimus ghiesbreghti, Pfr. in Malak. Blatt. xiii. p. 82 (1866)*; Novit. Conch. 11. p. 309, t. 75. 
figg. 6, 77; Monogr. Helic. Vivent. vi. p. 46°. . 
Bulimulus (Scutalus) ghiesbreght, Fisch. & Crosse, Miss. Scient. Mex., Mollusca, 1. p. 522, t. 23. 
fig. 4°. 
Bulimulus ghiesbreghti, Strebel, Beitr. Mex. Land- und Siissw.-Conch. v. p. 60, t. 6. fig. 14°. 
Hab. §. Muxico: Chiapas (Ghiesbreght 1~*) ; Tlacolula (Hége). 
BIOL. CENTR.-AMER., Terr. and Fluviat. Mollusca, August 1895. 27 
