510 MAZATLAN UNIVALVES 
serrantibus; apertura subelongaté ; labro intus yiui.-dentato ; 
labio parum extante, secundum strias spirales ad basin indentato. 
This species is described from young shells and fragments 
of adults. Portions of about a dozen specimens were found. 
The sculpture more resembles Metula, but the mouth is 
Anachoid. The ribs are not distinctly marked, except in the 
young shell; but undulate, with the interstices as in Pisania. 
The length of the adult is not known; lat. °13, long. apert. ‘1, 
div. 40°. 
Hab.—Mazatlan; extremely rare, off Spondylus; L’pool Col. 
Tablet 2428 contains 3 young shells and fragments. 
651. ANACHIS PYGM=A, Sow. 
Columbella pygmeza, Sow. Proc. Zool. Soe. 1832, p. 119 :— Thes. 
Conch. p. 141, no. 89, pl. 40, f. 163.— Mill. Syn. Nov. Test. 
Viv. p. 90.—Chénu, Conch. Ill. pl. 25, f.1,2.—C. B. Ad. 
Pan. Shelis, p. 97, no. 100. 
(Columbella} Anachis pygmea, H. & A. Ad. Gen. i. 184. 
Comp. Columbella costulata, C. B. Ad. Contr. Conch no. 4, 
p. 58, (Jamaica.) [ =A. pygmea, var. Panama, Bridges. | 
This shell is like a minute A. costellata, but there is scarcely 
any spiral sculpture except in the young shell, and round the 
base in the adult where it is very strong. The colour varies 
from light horn with a few‘purple-brown patches, to a nearly 
uniform black brown. The labrum has about 6 teeth; the 
labium wrinkled by the basal striez. The first four whirls are 
smooth and transparent, after which the normal sculpture 
appears. The ribs are well marked, but the interstices are 
not deeply chiseled. The smallest (nuclear) shell measures 
"03 by °022; the largest, long. °25, long. spir. °13, lat. ‘11, 
div. 40°. 
Hab.—St. Elena ; on dead shells, in sandy mud, 10 fm.; Cwm- 
tng.—Panama; common under stones at low water mark ; 
C. B. Adams.—Mazatlan ; extremely rare, on Spondylus ; 
L’pool Col. 
Tablet 2429 contains 7 young sp. in different stages of 
growth ; and 3 adult, differing in colour. 
652. ANACHIS GASKOINI, 2. s. 
A. t. parva, solidiore, subturrita ; albidé, lineis fuscis angustis 
sptralibus, anfr. ult v., penult. u.; inter posticas duas in costis 
