HELIX. 137 
Heliz (Discus) oajacensis (Koch), Fisch. & Crosse, Miss. Scient. Mex., Mollusca, i. p. 237°. 
Trichodiscus oajacensis (Koch), Strebel, Beitr. Mex. Land- und Siissw.-Conch. iv. p. 35°. 
Hab. S.W. Mexico: Oaxaca (Hegewisch 1-*), 
A somewhat doubtful species. According to the quoted descriptions and figures 
H. oajacensis seems to be sufficiently distinct from H. suturalis by the more elevated 
spire, the angulated periphery, and the two large dark chestnut bands. But it has 
not again been found, so far as is known. Strebel® thinks that it may have been 
an aberrant specimen of the preceding species. Hoge has found at the same locality, 
Oaxaca, a quite normal H. sutwralis, which with a diameter of 8 millim. has no trace 
of a keel; whereas H. oajacensis, with a diameter of 15 millim., according to Pfeiffer 
(162 millim. in Philippi’s figure), is said to be “ obtuse carinata.” 
11. Helix sumichrasti. 
Helix sumichrasti, Crosse & Fisch. in Journ. de Conch. xx. p. 147 (1872) ', and xxi. p. 265, t. 9. 
figg. 4, 4 a (1873) ”. 
Hab. E. Mexico: Soledad, between Cordova and Orizaba (Hége). 
S.W. Mexico: Isthmus of Tehuantepec (Swmichrast 12), 
Quite distinct by the keel of the shell. 
The locality ‘“‘ La Huallaga,’” Tehuantepec, quoted by Crosse and Fischer i is probably 
a mistake for Laoyaga (sometimes written Laollaga). 
12. Helix sargi. 
Heliz sargi, Crosse & Fisch. Journ. de Conch. xx. p. 146 (1872) *, and xxi. p. 277, t. 9. fig. 2 
(1878) ?; v. Mart. P. Z.S. 1875, p. 648°. 
Hab. N. GuateMata: in the woods of Tamahu, Vera Paz (Sarg }?); Coban (Salvin 3). 
H. sargi appears to be nearer to the subgenus Trichodiscina than to Lysinoé, but the 
authors do not mention any hairs or elevated points in their description of the species. 
Or it may, perhaps, be an angulated species of the section Praticolella. 
13. Helix macneili. | 
Helix mac-neili, Crosse, Journ. de Conch. xxi. p. 67 (1878) *, and xxii. p. 71, t. 2. fig. 3 (1874) * 
Pfr. Monogr. Helic. Vivent. vii. p. 451°; Angas, P. Z. S. 1879, p. 476%. 
Hab. S.W. Costa Rica, Terraba, on the banks of small streamlets (H. Pittier). 
E. & S.E. Costa Rica: coast region and lower hills from Parismina to the hills of 
Zhorquin (Gabb*); Chiriqui lagoon (MacNeil }~*). 
Very peculiar by two infolded spots in the last whorl, somewhat like those in Helix 
(Solaropsis) pellis-serpentis, Chemnitz, but in other respects agreeing well with the 
species of the subgenus Trichodiscina. ‘The specimen collected by H. Pittier exhibits 
BIOL. CENTR.-AMER., Terr. and Fluviat. Mollusca, March 1892. 18 
