468 {ANUAL OF THE MOLLUSCA. 
Animal (of C. solenoides) with mantle-lobes united, cirrated 
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 Cypricardia rostrata, Lamarck, Philippines (Fig. 
PP 300), with mantle-lobes united, 
LZ ~ and covered with wrinkled epi- 
2. PY BL XT >JE\XK «dermis; siphonal orifices fringed; 
, eaq\\ gills deeply plicated, anterior 
y)) part of the outer gill united to 
the inner ; dorsal border narrow, 
plaited ; adductor muscles of two 
elements, 
Distribution, 18 species. Red Sea, India, and Australia. In 
crevices of rock and coral. 
Fossil, 60 species. Lower Silurian —. North America and 
Europe. 
? Sub-genera. Coralliophaga, Bl. C. coralliophaga, Lamarck. 
Shell long, cylindrical, thin, slightly gaping behind; hinge- 
tecth 2.2, and a laminar posterior tooth; pallial line with a wide 
and shallow sinus. Distribution, 5 species. Mediterranean, in 
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. Rep., 1841. (San-~ 
euinolites, M‘Coy.) Employed for Cypricardia-shaped shells of 
the paleeozoic rocks; some of them are more nearly related to 
Modiola (vy. Modiolopsis, p. 422), but they bear no resemblance 
to Sanguinolaria. 
Goniophora, Phillips, 1848. Cypricardia cymbeeformis, Sby- 
Upper Silurian, Britain (Mytilide ?). 
Fig. 261. Cypricardia. 
PLEUROPHORUS, King, 1848. 
Type, P. costatus, Brown. Permian, England. (Pal. Trans., 
1850. Pl. XV., Figs. 13—20.) 
Synonyms ? Cleidophorus, Hall (cast only). Unionites, Wissm. 
? Mzeonia, Dana. 
Shell oblong ; dorsal area defined by a line, or keel; umbones 
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. 
