MYODORA. 



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The siphons of Pandora are short and united, with the 

 ends diverging and fringed ; the mantle is closed, except a 

 small aperture for the narrow, linguiform foot. The outer 

 layer of the shell, as shown by Dr. Carpenter, is composed 

 of regular, vertical, prismatic cells, two hundred and fifty 

 times smaller than those of Pinna. The species of Pan- 

 dora are found burrowing in sand and mud, and are met 

 with at depths varying from four to one hundred and ten 

 fathoms. Britain, Spitzbergen, the United States, the 

 Canary Islands, India, New Zealand, and Panama afford 

 examples of this genus. 



Species of Pandora. 



arenata, Sow. 

 Ceylanica, Sow. 

 cistula, Gould. 

 claviculata, Cpr. 

 coruuta, C. B. Adam*. 

 depressa, Sow. 

 discors, Sow. 

 flexuosa, Donov. 

 glacialis, Leach. 



insequivalvis, Linn. 

 oblouga, Sow. 

 obtusa, Leach. 

 punctata, Com: 

 radiata, Sow. 

 striata, Quoy. 

 tabacea, Gronov. 

 trilineata, Say. 

 unguiculus, Soiv. 



Genus MYODORA, Gray. 



Shell triangularly ovate; inequivalve, right valve more or 

 less convex, left valve flat ; anteriorly rounded, posteriorly 

 slightly flexuous, contracted and truncate ; pearly within. 

 Hinge with two elongate teeth diverging from the beak in 

 the right valve, the hinder flat and rather obsolete, and two 

 grooved ridges in the left valve ; cartilage internal, in a 



