MTSCfi:. 209 



circumstance tlie word Cliama is added to its name ; the little 

 testaceous appendage bringing it near the Myarise. M. anom- 

 oides. PI. iii. fig. 73, 74. 



MTOCOJSTCHA. Sow. {Mya and Concha.) Fam. Cardiacea, 

 Lam. Bescr. Oval, equivalve, oblique ; umbones terminal ; 

 ventral margin rounded ; binge with an external ligament, and 

 one oblique, elongated tootb in tbe left valve ; impression of the 

 mantle not sinuated. — Obs. The fossil genus has the general form 

 of Mytilus or Modiola, but the hinge of the Conchae generally. 



MTODOEA. Grray. Eeeve, Conch. Icon. Bivalve, for the most 

 part triangular, inaequivalve ; left valve concave, right valve 

 flat ; anterior side rounded ; posterior side flexuous, truncated ; 

 hinge, with linear projections on each side of a triangular liga- 

 mentary pit, and a bony appendage. Ex. Myodora striata, PI. 

 xxvii. fig. 574. 



MYOPAE/A. Lea. (Myoparo, a piratical oar-galley.) Fam. Ar- 



, cacea, Lam. A genus founded on a minute fossil bivalve shell, 

 somewhat resembling Isocardia in form, but having a series of 

 teeth placed on each side of the umbones. M. costatus, J*l. vii. 

 fig. 135, 



MTEISTICA. Sw. A genus of "PyruHn»," Sw. thus described: 

 " Sub-pyriform ; spire strong, spiny, or tuberculated, nearly as 

 long as the base ; umbilicus either partially or entirely concealed ; 

 inuer Hp vitreous, thin ; the outer with an internal and ascending 

 canal ; the basal channel wide. Hippocastanea. En, M. 432. f. 4. 

 liueata, lb. f. 5. melongena. En. Meth. 435. f. 3. nodosa. Chem. 

 1564. 5." Sw. p. 307. Ex. P. Melongena. PL xxvi. fig. 552. 



MYETEA. Turt. Ven¥S spinifera, Auct. Ltjcina spinifera 



, Nonnull. The shells of this genus are described as " Oval, 

 triangular, equivalve, nearly equilateral, closed. Hinge of one 



. valve with a single tooth, and lateral one oh each side; of the 

 other valve with two teeth, the lateral ones obscure. Ligament 

 external." British Channel and Mediterranean. 



MYSCA. Turt. A genus composed of species of TJnio, Auct. 



. which are distinguished by having " strong, transverse, notched, 

 cardinal and long lateral teeth." TJnio pictorum. 



p 



