MAZATLAN UNIVALVES 177 
Helix (Cochlostyla) princeps, D’ Orb. Synops. p. 8. 
Orthalicus princeps, Beck. Ind. p.59, no. 3. 
Achatina pulchella, Spzx. 
This well known and widely distributed species is the only 
land shell which appears at all common at Mazatlan. It varies 
greatly in pattern, as will be seen by the following list. Most 
of the shells were young, but characteristic. ‘The first 3 or 4 
whirls rarely display any painting. Long. 2°1, lat. 1°1. 
Hab.—Brazils, Peru, Columbia, D’ Orbigny.—Cuba, Sagra.— 
Conchagua, Broderip.—Mazatlan ; common; L’pool Col. 
Tablet 796 contains 5 sp.; with very large dark patches.— 
797, 4 do. patches diagonal.—798, 3 do. patches smaller.—799, 
1 do. patches clouded.—800, 5 do. gathering into knots.—801, 
7 do. normal painting, knotted in spiral bands.—802, 4 do. very 
fine, scarcely zigzag stripes.—803, 3 do. irregularly crowded.— 
804, 4 do. knotted pattern extremely faint.—805, 3 do. yellow- 
ish, with spiral brown lines at the base.—806, 1 sp. yellowish, 
without pattern.—807, 5 sp. elongated form.—808, 1 sp. with 
winter epiphragm.— 809, 3 sp. broken and mended by the 
animal. 
233. ORTHALICUS ZIEGLERI,. Pfr. 
Bulimus Ziegleri, Pfr. Proc. Zool. Soc. 1846, p. 113, no. 25 :— 
Symb. no. 472. 
Leiostracus Ziegleri, H. §& A. Ad. Gen. vol. ii. p. 151. 
This shell is placed by Messrs. Adams in a subgenus of 
Otostomus. It has however asharp, non-reflected lip; as well 
as a very small, scarcely covered umbilicus. A very few speci- 
mens were found with the Phys. An unusually large one, in 
which the linear patches of colour are almost evanescent, 
measures long. 69, long. spir. °35, lat. 34. 
Hab.—Central America, Largilliert—Mexico, Liebmann.— 
Mazatlan ; extremely rare; L’pool Col. 
Tablet 810 contains 2 sp., one of normal colouring, the other 
the pale variety. 
234. OrtHaticus ? Mrexicanus, Lam. 
Bulimus Mexicanus, Lam. An. s. Vert. vol. viii. p. 232, no. 23.— 
Val. in Humb. Rec. Zool. 
Leiostracus Mexicanus, H. & A. Ad. Gen. ii. 150. 
= Helix vittata, Daud. Hist. Moll. no. 397. 
