206 MOLLUSCA. 
by Strebel. Strebel also mentions ® specimens with spiral rows of small pellucid spots, 
which may form a transition between the forms 6 and c. He suggests that the 
aperture of Pfeiffer’s original specimen may be somewhat deformed, and in this I am 
inclined to agree with him. 
I prefer to write “ chiapensis,” because Chiapas seems to be the Spanish plural form, 
the city being called Chiapa in older works. 
9. Otostomus castus. (Tab. XII. figg. 16-21.) 
Bulimus castus, Pfr. P. Z. S. 1846, p. 112’; Monogr. Helic. Vivent. ii. p. 47°; Reeve, Conch. 
Icon. v., Bulimus, t. 45. fig. 282°; ? Tate, in Am. Journ. Conch. v. pp. 152, 156 (1870) *. 
Bulimus (Leiostracus) castus, Pfr. in Malak. Blatt. ii. p. 153 (1855)’. 
Otostomus (Leiostracus) castus, H. & A. Adams, Gen. Moll. ii. p. 151°. 
Bulimulus castus, v. Mart. in P. Z. 8. 1875, p. 6487. 
Bulimulus (Drymeus) castus, Fisch. & Crosse, Miss. Scient. Mex., Mollusca, i. p. 485, t. 24. 
figg. 11, 11 a-d*. 
A. typwus: minor (long. 19-23, diam. 11, apert. 10-124 millim.). 
a: unicolor, albus, peristomate plus minusve roseo. 
b: irregulariter fusco-strigatus. (Fig. 17.) 
c: fasciis tribus fusco-nigris interruptis (Reeve, loc. cit. fig. 282) vel continuis. (Figg. 18, 19.) 
Hab. Centrat AMERICA: probably Vera Paz (Delattre1~4: var. a). 
N. GuatemaLa: Coban (Morelet *, Salvin?: varr. a, 6, c); Tamabu (Sarg §). 
B. xantholeucus: major, paullo magis ventricosa (long. 25, diam. 14, apert. 15 millim.); alba, apice et peri- 
stomate subinde flavescentibus. (Figg. 16, 16a.) 
Hab. N. Guatemata: Sabo, in a tributary valley of the River Polochic, at an elevation 
of 3300 feet above the sea (Champion). 
C. porrectus: elongatus, gracilior (long. 30-35, diam. 14-15, apert. 18-19 millim.). 
a: unicolor, albus, columella sola rubescente. (Fig. 20.) 
(Bulimulus castus, var. 6, Fisch. & Crosse, loc. cit. fig. 11 5.) 
6: fasciis 2-3 violaceo-fuscis, apertura rosea. 
(Bulimulus castus, var. y, Fisch. & Crosse, loc. cit. figg. 11lc, d.) 
c: parce strigatus, columella sola rosea. (Fig. 21.) 
Hab. N. Guatemata: Coban or Tamahu (Morelet or Sarg: varr.a, 6); Vera Paz (Stoll: 
varr. 6, ¢). 
The three varieties, A, B, C, appear to be distinct at first sight, but there are transitions 
between them in size, form, and colour. For example, one of Dr. Stoll’s specimens 
from Vera Paz (fig. 21) is only 27 millim. long, but it exhibits the slender figure and 
more solid shell of var. C. 
Fischer and Crosse § do not give separately the localities for the different varieties 
which they have described and figured. Tate‘ doubtfully records the occurrence of 
the species in Nicaragua—“ in the mountain-forests of Javali and Pefia Blanca, at an 
elevation of about 2500 feet above the sea,” and at “Chontales”; he does not mention 
