462 MOLLUSCA. 
for the locality quoted, is without doubt the dealer Gustay Schneider, of Basle, wlio 
had Dr. Stoll’s shells for sale. 
19. Pachychilus schiedeanus. : 
Melania schiedeana, Philippi, Abbild. neuer Conch. i. p. 62, t. 2. fig. 11 (1843) *; Reeve, Conch. 
Icon. xii., Melania, t. 15. fig. 1017; v. Mart. in Malak. Blatt. xii. p. 51 (1865) °; Strebel, 
Beitr. Mex. Land- und Siissw.-Conch. i. p. 35, t. 4. figg. 37, 37 a*; Brot, in Martini & 
Chemnitz, Syst. Conch.-Cab. ed. 3, Melaniaceen, p. 42, t. 5. figg. 6, 6a’. 
Vibex (Juga) schiedeana, H. & A. Adams, Gen. Moll. i. p. 305°. 
Pachychilus schiedeanus, Troschel, Gebiss d. Schnecken, i. p. 116, t. 9. fig. 3 (radula)"; Fisch. & 
Crosse, Miss. Scient. Mex., Moll. ii. p. 866, t. 50. figg. 10, 10a, 5°. 
Melania variegata, Wiegmann, in Mus. Berol.*; Menke, Synops. Moll. p. 43 (1880) (sine descr.) ". 
The most slender and acute of all the Central-American species, but varying somewhat in this respect. The 
peristome is distinctly thick and obtuse, somewhat expanded below; colour usually pale brown, with 
more or less distinct reddish-brown stripes. 
Hab. E. Mexico: Rio de Misantla, in the hot region, on stones (Deppe & Schiede *) ; 
Arroyo Viejo, three miles from Misantla (Strebel +); Misantla and Cordova (Hége) ; 
Coatepec (Strebel, in Mus. Berol.), 
% CentRAL Mexico: in small brooks and ditches around the city of Mexico (Schiede }). 
Although the last-named locality seems very precise, yet I have some misgiving 
about it, for the following reasons: (1) on the labels of the Berlin Museum, from the 
time of Wiegmann (+1841), Misantla is named as the habitat in which this species 
was found by Schiede, and it is also noted as from the “heisse Region” (tierra 
caliente); (2) no subsequent collector has found it there, not even Prof. A. Heilprin, 
who collected in the environs of the city of Mexico in 1890 (¢f. Proc. Acad. Phil. 1892, 
pp. 825-831). The occurrence at Misantla, on the contrary, is corroborated by both 
Strebel and Hoge. 
Troschel has examined the radula and found it to be like that of P. levissimus, the 
type of the genus. 
Var. sirebelianus. 
Melania saussurei (Brot ?), Strebel, loc. cit. p. 36, t. 4. figg. 48, 43 a™. 
Pachychilus schiedeanus, var. strebeliana, Fisch. & Crosse, loc. cit. p. 869". 
Whorls more rounded. A somewhat doubtful form, apparently very different from the preceding, 
Hab. E, Mexico: stream of Palpoala, close to Misantla (Strebel 11), 
20. Pachychilus saussurei. 
Melania saussurei, Brot, in Rev. Zool. 1860, p. 264, t. 17. fig. 11°; in Martini & Chemnitz, Syst. 
Conch.-Cab. ed. 2, Melaniaceen, p. 48, t. 5. fig. 7°. 
Pachychilus saussurei, Fisch. & Crosse, Miss. Scient. Mex., Moll. ii. p. 868 *. 
Shell with three rows of granular elevations beneath the suture ; otherwise near P. schiedeanus. 
