BIVALVES _. MACTRA. 35 
Scientific Name. Locality. Common Name. 
Solida -++++++++> Britain ---+--++++ +:++> Strong Mactra -- 
Solidissima «+++ ++ North America ----:::+ Thick ---- do: 
Truncata -+---+- Britain-----++s+++seee%* Truncated- do -- 
Subtruncata - ---- Britain -+-+-+-++- cesses Abrupt---- do -- 
Australis ++-++-- New Zealand --**-:+:: Southern -- do - 
Piperata --+-+ -- Mouth ofthe Niger: ----- Pepper -+++ do 
Tenuis ---scs+:; Britain «-cccesssseeeece Thin ---+-- do - 
Boysii Srarerets(avaiel ee Ditto «--- 2. ees ee veces Boys’ doco Gor 
Division J1.—Shell ovate, oblong. 
Famity 1.—Closed at both ends. 
Glauca --+++9+:> Spain and Britain ------ Red rayed - do -- 
Rugosa --+-++--- Mediterranean, Nicobar- Rugged---+ do - 
Egyptiaca otetetey: Red Sea << .-- 0 eee-e us Egyptian 2» GO -- 
Famity 2.—Gaping at the anterior end. 
Pellucida ------- Guinea--.--.---.- »-- Pellucid- - do-- 
Fragilis --------- Britain, Nicobar -- ++ -+-- Brittle ---- do -- 
LLTR Te ooo onde DrstGhin ooo cotobancod0S Lister’s:--» do «+ 
Famity 3.—Gaping at both ends. 
Planata +---+---- Tranquebar, Britain ---- Flattened-- do - 
Joutraria ----*-. [bist jin) ci conodopodtio hoe Muddy soo Wt or 
“Serie balococ ago ID iinsosionadod oomoosidés Gaping Hho rte oc 
