246 INTKODUCTIO^' TO CONCHOLOGY. 



Family I. Ostracea. 



Methinks tlie spirit of peace doth seem to brood 

 Among the rocks and on the sounding shore ; 

 "While, sweeping onward from the wondi'ous deep. 

 The billows come and go, in ceaseless play, 

 Spreading upon the sands those rich deposits 

 Of shells, and sea-weeds, corals, corallines, 

 Borne up, perchance, from many fathoms deep 

 In the vast world of waters, moving ever 

 "With congregated roar, or solemn rushing 

 Upon the sea-sand, stiUing aU vain fancies, 

 Filling the calm and listening ear of thought 

 With serious words. 



The Ostracea are somewhat allied to the Fectinaeea, but 

 differ in many essential peculiarities ; and the passing out 

 of a bony tendon through an orifice in the shell in two of 

 the genera^ is a new and peculiar feature. 



Shells of the Ostracea may be described as being at- 

 tached, irregular, either foliated or laminar, and rarely 

 auriculated ; they are moreover thin, sometimes quite trans- 

 lucent, and one valve is always larger than the other. The 

 ligament is either internal or semi-internal. 



Ostracea are divided into four genera — Ostrea, Flacunay 

 Placunanomia, and A?iomia. 

 The shell of Ostrea is attached, inequivalve, and irregular. 



