468 



MAircTAL OF THE MOItTTSCA. 



Animal (of C. solenoides) with mantle-lobes united, cirratel 

 behind ; pedal opening moderate ; foot small, compressed, with 

 a large byssal pore near the heel ; siphons short, conical, unequal, 

 cirrated externally ; orifices fringed ; palpi small ; gills unequal, 

 the outer narrower and shorter, deeply lamellated, united 

 posteriorly, the inner prolonged between the palpi. 



Animal of Ct/joricardia rosfrafa, Lamarck, Philippines (Fig. 



300), with mantle-lobes united, 

 and covered with wrinkled epi- 

 dermis ; siphonal orifices fringed; 

 gills deeply plicated, anterior 

 part of the outer gill united to 

 the inner ; dorsal border narrow, 

 plaited ; adductor muscles of two 

 elements, 

 Eed Sea, India, and Australia. In 



North America and 



Fig, 261. Cypricardia, 



Distribution, 13 species, 

 crevices of rock and coral. 



Fossil, 60 species. Lower Silurian 

 Europe. 



? Sub-genera. Coralliophaga, Bl. C. coralliophaga, Lamarck. 

 Shell long, cylindrical, thin, slightly gaping behind ; hinge- 

 teeth 2.2, and a laminar posterior tooth ; pallial line with a wide 

 and shallow sinus. Distribution, 5 species, Mediterranean, iji 

 the burrows of the Lithodomus ; sometimes two or three dead 

 shells are found one within the other, besides the original owner 

 of the cell ; South Sea. 



? Cypricardites, Conrad (part). An. Geol. Eep., 1841. (Sap.- 

 guinolites, M'Coy.) Employed for Cypricardia-shaped shells of 

 the palaeozoic rocks ; some of them are more nearly related to 

 Modiola (v. Modiolopsis, p. 422), but they bear no resemblance 

 to Sanguinolaria. 



Goniophora, Phillips, 1848. Cypricardia cymbseforrais, Sby. 

 Upper Silurian, Britain [MytilidcE ?). 



Pletjeophoeus, King, 1848. 



Type, P. costatus. Brown. Permian, England. (Pal. Trans. j 

 1850. PL XV., Eigs. 13—20.) 



Synonyms ? Cleidophorus, Hall (cast only). Unionites, Wissm. 

 ? Mseonia, Dana. 



Shell oblong ; dorsal area defined by a line, or keel ; umboneg 

 anterior, depressed; hinge-teeth 2.2; laterals 1.1; elongated 

 posterior ; anterior adductor impression deep, with a small pedal 

 scar close to it, and bounded posteriorly by a strong rib from the 

 hinge ; pallial line simple. 



