ho 
QO 
MAZATLAN BIVALVES 
39. PSoLECURTUS , sp. ind. 
Tablet 91 contains a fragment very flat, white, thin, with 
irregular very fine strix, shewing within as well as without. 
Hab.—Mazatlan : in Spondylus washings; L’pool Co’. 
Famity TELLINID®. 
Genus SEMELE, Sehum. 
Syn. Amphidesma, Lam. 
40, SEMELE PRoxima, C. B. Ad. 
Amphidesma proximum, C. B. Ad. Pan. Shells, p. 289, no. 487. 
Amphidesma proxima, (se.-um) Rve. Conch. Ic. Amph. pl. 3, 
£120, 
So much does this species vary in outline, and so closely do 
some forms approximate to 8. elliptica, that it is still an open 
question whether C. B. Adams did right in separating it. The 
colour is typically orange within, and the pallial poytion is 
punctured. 
Hab.—Panama, rare, C. B. Adams.—Mazatlan; common ; 
L’pool Col. 
Smallest specimen measures long. °04, lat. °05, alt. 02, 
Largest s ae BOOSH oo sizes 
Transverse ,, e, Peart atthe teas 
Tablet 92 contains a pair and a valve, extremely young, which 
probably belong to this species, though there are lateral teeth 
slightly developed.—93, 5 specimens, normal state.—94, 5 speci- 
mens more oblong.—95, 3 specimens very regularly rounded.— 
96, 3 specimens, very transverse.—97, 4. young specimens, with 
very light epidermis.—98, 2 specimens shewing interior.—99, 2 
pairs and a valve, deformed in growth. 
41. SeMELE Pvenusta, A. Adams. 
Proc. Zool. Soc. 1853, p. 96. 
Amphidesma venusta [sc.-um] Fve., Conch. Ic. Amph. sp. 3. 
ply f. 3: 
Tablet 100 contains a young valve which agrees in the main 
with this species. The concentric ridges are not developed, 
