MACROCERAMUS. 289 
Another variety occurs in Texas with 104 whorls and few scattered papilla, 94-10 
millim. long, found near Dallas by Dr. Boll (Strebel, loc. cit. p. 90, t. 5. fig. 4 d). 
The apex of the shell is ordinarily of a pale brownish hue in specimens from 
Guatemala, as well as in those from Mexico and Texas; a dark blackish colour of the 
apex has been observed in examples from Guatemala (Morelet) and from Texas (Strebel). 
M. pontificus, A. Gould, from Florida, seems to differ in having the papilla numerous 
and regular, corresponding to each second costa and somewhat lengthened, the aperture 
less oblique, the peristome more circular, and the white colour prevailing on the shell. 
Length 11-18 millim. [Binney, Terr. Air-breath. Moll. U.S. t. 69. fig. 1; Land and 
Freshw. Moll. of N. Am. i. p. 220 (kieneri).] 
2. Macroceramus kieneri. 
Bulimus kieneri, Pfr. P.Z.S. 1846, p. 40°; Monogr. Helic. Vivent. ii. p. 79’; Martini & Chemnitz, 
Syst. Conch.-Cab. ed. 2, Bulimus, p. 131, t. 42. figg. 23, 24°. 
Hab. Honpuras (Dyson 123), 
Seems to differ from the preceding by the want of the white papille at the suture, 
although this is also crenated by the costule. Pfeiffer subsequently (Monogr. Helic. 
Vivent. iil. p. 365) identified it with the Floridan W. pontificus, A. Gould, and then 
separated it again from that species (op. cit. vi. p. 350, and vill. p. 419), adding, in the 
latter case, Florida as locality. In a similar manner, he gives (op. cit. vi. p. 350) 
Yucatan as a locality for WZ. gossei, Pfr., because he had at one time (op. ct. 11. p. 566) 
identified this Jamaican species with MZ. concisus. 
3. Macroceramus denticulatus. | 
Cylindrella denticulata, Pir. Monogr. Helic. Vivent, i. p. 580°; Martini & Chemnitz, Syst. Conch.- 
Cab. ed. 2, Oylindrella, p. 65, t. 7. figg. 14, 15°; Sowerby, in Reeve’s Conch. Icon. xx. 
Cylindrella, t. 3. fig. 22°. 
Macroceramus denticulatus, Fisch. & Crosse, Miss. Scient. Mex., Mollusca, 1. p. 424 *. 
Hab. Mexico (Mus. Cuming }~*). 
This species does not appear to have been found by later collectors, and, as all the 
other forms allied to it are peculiar to the West-Indian Islands, it is doubtful if it is 
really Mexican. 
Fam. STENOGYRIDZ. 
Generally small, unicolorous shells of oblong or turrite form. Jaw simple, slightly 
striated. Median tooth of the radula much smaller than the next lateral teeth. 
They live chiefly on the ground, and are often carried great distances with green- 
house-plants or with vegetables. | 
BIOL. CENTR.-AMER., Terr. and Fluviat. Mollusca, April 1898. 37 
