78 MOLLUSCA. 
G. Difficiles. 
49. Glandina difficilis. 
Glandina difficilis, Crosse & Fischer, in Journ. de Conch. xvii. p. 426 (1869) ‘; Fischer & Crosse, 
Miss. Scient. Mex., Mollusca, i. p. 182, t. 6. figg. 3, 3a°; Strebel, Beitr. Mex. Land- und 
Siissw.-Conch. i. p. 54°. 
Oleacina difficilis (Cr. & Fisch.), Pfr. Monogr. Helic. Vivent. viii. p. 328 4 
Hab. Mexico: probably in the environs of Orizaba (Botteri! *). 
This shell exhibits a distinctly twisted columella, by which it approaches some- 
what to Streptostyla ; in other respects it resembles some of the smaller species of the 
group “Turrite.” Strebel® thinks that it may be nearer allied to G. ambigua, but 
he has not himself examined a specimen. 
The following four species probably do not enter within the limits of this work; 
but as some well-known authors have admitted them among the Mexican or Central- 
American species, I also am obliged to enumerate them here, in order to ascertain 
their probable geographical distribution. Two of them are the first known species of 
the genus, and their synonymy, chiefly that of the older authors, is somewhat intricate. 
50. Glandina truncata. 
—— ——, Lister, Hist. Conch. ed. 2, App. t. 4. (1059), fig. 4 (1770) °. 
, Kammerer, Conch. Cab. d. Erbp. v. Schwarzb.-Rudolst. p. 128, t. 10. fig. 5 (1786) *. 
Bulla truncata, Gmel. Syst. Nat. i. 6, p. 8434 (1788-1791) ’. 
Glandina truncata, Say, Amer. Conch. ii. t. 20 (1831) *; Beck, Ind. Moll. p. 78°; Binney, Terr. 
air-breathing Moll. U.S. ii. p. 301, tabb. 59, 60°, & v. p. 84°; Land- and Freshw.- 
Shells of N. Am. i. p. 15°; Manual of Amer. Landshells, p. 348°; Tryon, in Am. Journ. 
of Conch. ii. p. 225, t. 16. fig. 1, 2'° ; Strebel, Beitr. Mex. Land- und Siissw.-Conch. 11. 
pp. 5-7, t. 3. fig. 1", & i. p. 7”. 
Achatina truncata (Gmel.), Pfr. Monogr. Helic. Vivent. ii. p. 287*°; Reeve, Conch. Icon. vi., 
Achatina, t. 18. fig. 47 ™. 
Oleacina truncata, Gray, Cat. Pulm. p. 23 (1855); Pfr. Monogr. Helic. Vivent. iv. p. 638°. 
Polyphemus glans, Say, Journ. Acad. Phil. i. p. 282 (1817-1818) (nec Montf.) *. 
Helix rosea, Férussac, Prodr. p. 50. no. 356 (1821-1822) *; Hist. Nat. Moll. Terr. t. 135. 
fig. 3”. 
Achatina rosea, Gray, Ann. Philos., new ser. ix. p. 414 (1825) *; Deshayes, Encycl. Méth. ii. p. 10 
(1830) *. 
Achatina striata, Deshayes, in Lamarck’s Syst. Anim. sans Vert. ed. 2, viii. p. 313 (nec Miill.) *. 
Hab. SoutHeRN Unirep States: Atlantic and Gulf States from South Carolina to 
Florida 4 1”, Louisiana §, and Texas®; very common on the islands and keys along 
the coast ’, also in the marshes behind the coast sand-hills 4; inland—as far north 
as Macon in Georgia, Bibb County in Alabama, and Jackson in the State of 
Mississippi 9. 
