28 MAZATLAN BIVALVES 



39. PSoLEcrRxrs , sp. ind. 



Tablet 91 contains a fragment very flat, wliite, i\im» with 

 irregular very fine stria, shewing within as well as without. 

 Hah. — Mazatlan : in Spondylus washings ; L'pool Col. 



Pamilt TELLINID.^. 



Genus SEMELE, Schum. 

 Si/n. Aniphidesma, Lam. 



40. Semele peoxima, C. B. Ad. 



Amphidesma proximum, C. B. Ad. Pan. Shells, p. 289, no. 487. 



Amphidesma proxima, {sc. -um) JRve. Conch. Ic. Amph. pi. 3, 



f. 20. 



So much does this species vary in outline, and so closely do 

 some forms approximate to S. eUiptica, that it is still an open 

 question whether C. B. Adams did right in separating it. The 

 colour is tj-picaUy orange within, and the paUial portion is 

 punctiu'ed. 

 Hah. — Panama, rare, C. B. Adams. — Mazatlan ; common ; 



L'pool Col. 



Smallest specimen measures long. '01, lat. '05. alt. "02, 



Largest „ „ „ 2-36, „ 2o, „ I'ZS, 



Transverse „ „ „ 2'03, „ 2"36, „ 1'17. 



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 oblonc — 95, 3 specimens very regularly rounded. — 

 96, 3 specimens, very trausvei"se.— 97, 4 yoimg 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 veuusta [sc.-um] Bve., Conch. Ic. Amph. sp. 3. 



pi. 1, f. 3. 



Tablet 100 contains a young valve which agrees in the main 

 witli this species. The concentric ridges are not developed. 



