148 MOLLUSCA. 
c. hégeana: depresso-globosa, subleevis, pallide rufescens, strigis albis, fasciis distinctis, subinterruptis: diam. 
27-33, alt, 221-28 millim. (Figg. 20, 21.) 
Helix humboldtiana (part.), Pfr. in Martini & Chemnitz, loc. cit. t. 92. fig. 19. 
Hab. NortuH Mexico: Chihuahua (/6ge). 
d. buffoniana: dilatato-globosa, major, subcastanea, fasciis minus distinctis, strigis flavo-albidis, plicis validi- 
oribus: diam. 41-45, alt. 38-39 millim. 
Helix buffoniana, Pfr. in Zeitschr. fir Malak. 1845, p. 152"; Philippi, Abbild. neuer Conch. ii. 
p. 183, t. 9. fig. 2°; Pfr. in Martini & Chemnitz, loc. cit. p. 151. no. 589, t. 92. figg. 11- 
13, and Monogr. Helic. Vivent. i. p. 196%; Reeve, Conch. Icon. vii., Helix, t. 102. 
fig. 565°. 
Helhiz humboldtiana, var. 8. buffoniana, Pfr. Monogr. Helic. Vivent. iii. p. 182%; v. Mart. in 
Malak. Blatt. xii. p. 16 (1865) ™. 
Helix (Pomatia) humboldtiana, var. 8. buffoniana, Fisch. & Crosse, loc. cit. p. 240, t. 11. fig. 2". 
Arionta humboldtiana, var. 8. buffoniana, Strebel, Beitr. Mex. Land- und Siissw.-Conch. iv. 
p. 35. 
Helix matronula, Uhde, in litt. *. 
Hab. Centra, Mexico: Rio Frio", route Mexico to Puebla!® (coll. Gruner); 
environs of the city of Mexico (Boucard '8) ; Mexico, without nearer indication of 
locality (probably near the city) (Uhde 1"). 
e. badiocincta : conoideo-dilatata, major, sublevis, pallide brunnea, fasciis latioribus perdistinctis: diam. 40, 
alt. 36 millim. (Figg. 22, 22a.) 
Helix badiocincta, Wiegmann, in litt. (Mus. Berol. circa 1887) **. 
Helix aspersa, Binney, Terr. air-breath. Moll. N. Am. iii. t. 43 (nec Miill.) *. 
Heliv humboldtiana, var. a, v. Mart. in Malak. Blatt. xii. p. 16 (1865) (part.) ®. 
Arionta humboldtiana (Val.), Tryon, Am. Journ. Conch, ii. pp. 318, 327, t. 23 (6). fig. 17%. 
Hab. Mexico: without nearer indication of locality (probably near the city of Mexico) 
(Deppe 2" 28), 
This species has the general appearance of the subgenus Pomatia, and the var. 
buffoniana bears a remarkable resemblance at first sight to H. subplicata, Lowe, from 
Porto Santo, or H. mazullii, Jan, from Sicily ; but in both these the umbilicus is quite 
closed by the columellar margin. J. humboldtiana differs, however, from all known 
species of Pomatia by the granulation of the surface of the shell, a character bringing 
it rather near to H. eximia, as Fischer and Crosse have already stated. This granula- 
tion is most distinct in the var. bugfoniana, rather obsolete, but still perceptible, in 
var. hogeana, intermediate in badiocincta and hegewischi; it is not confined to the 
cuticula (epidermis), but is also visible in the calcareous shell beneath the cuticula. 
The varieties which are here enumerated have, at first sight, a very different aspect, 
but they are connected by intermediate gradations: thus, there is a specimen from 
Chihuahua quite intermediate between var. hégeana and var. badiocincta (diam. maj. 36, . 
