368 



SHELLS AND SHELL-PISH. 



PART II. 



Pandora Lam. Inequivalve, thin, rostrated, perlaceous ; 



one valve flat, the other convex ; ligament internal ; 



umbones small; cardinal teeth ~ , lamellar, sagittate, or 



like aV reversed: connected to Anatina.^fig. 1 17. </,&.) 



P. rostrata. En. Meth. 251. f. 1. 



MACTRA Linn. Equi valve ; the valves slightly gaping 

 on one side ; ligament internal and external ; cardi- 

 nal teeth complicated. 



Lutraria Lam. Shell thin, transversely oval or oblong; 

 cardinal teeth -f , angular, followed by a spoon-shaped 

 lobe containing the cartilage ; lateral teeth none. 

 (fig. 118. b.) 

 L. compressa. En. M. 257. f. 4. papyracea. Sow. Gen. f. 2. 



Mactra Linn.* Transversely oval or sub-trigonal ; um- 

 bones prominent ; cardinal teeth |, angular, some- 



times with additional laminae ; cartilage entirely in- 

 ternal, nearly central; lateral teeth -i. (fig. 118. c.) 

 Neapolitana. Poli. Test, stultorura. En. M. 265. f. 2. 

 pi. 18. f. 15. turgida. Sow. Gen. f. 2. 



Schizodesma Gray. General character of Mactra ; but 



* Including Mactra bicolor, &c., Auct. 



