of Tiir. i \mii.\ 01 \ \i \in>. I 1 i 



be double in the right; lateral tooth lameiliform and double 

 in the lefl valve only, the 1 \v<» teeth form one continuous 

 curve line, somewhat abrupt at both terminations, more bo 

 at the anterior one: anterior cicatrices distinct; posterior cica- 

 trices confluent; dorsal cicatrices very perceptible. Cavity 

 of the beaks wide and very shallow; nacre purple and irides- 

 cent. 



Remarks. — This beautiful shell most resembles the Sym- 

 phynota alata in its general form, l>nt its posterior wing is less 

 elevated. The colour of it> oacre i^ the same. It differs 

 entirely, however, in the cardinal tooth, and in possessing the 

 anterior connate whig. A metallic sound is produced hy 

 dropping one valve into the other, which is very remarka- 

 ble, and is caused by the density of the calcareous matter of 

 the nacre, which is very thin. The epidermis i- exceedingly 

 smooth and glossy. 



2. Symphynota Bi-alata. Plate XIV. fig. 24. 



Tesli'i ovato-triangttlari, in<equUaterali, transversim rugosd, aub-ven- 

 tricosA; margme doraali buaUttd ; valwdis tenuUms, ante et i»<si nates 

 connotis : natibtts et ala poaterioris basi apiceque undvlatia; natibiu 

 luiurf promiru ntibus ; <Unh lametttformi unico in valvuld utrdqvt ; I 

 mento eclat o ; margaritd tenuiet iridescente. 



Shell triangular-ovate, inequilateral, transversely wrinkled, sub-v< n- 

 i ricr>.<f • : dorsal margin raised into two wings; valves thin, connate I" fore 

 .-Hid behind the beaks : beaks and the base anil Bummil of the posterior 



wing undulated ; beaks not prominent ; i ne li illiform carved tooth in 



each valve ; ligament concealed; nacre thin, pearly, and iridi set at 



Hah fresh waters of the south of \ Brought 



from Canton by Captain Ban*. 



Mv Cabinet. 



Cabinel of Mi' Pierpoint 



Cabinet of Mr Hyde. 



Cabinel of Mi Phillips. 



