^54 MANUAL OP THE MOLLUSCA. 



Shell usually sinistral, flat, or concave above; aperture 

 quadrangular. 



Platystoma (Suessi) Homes, 1855. Trias, Hallstadt. 



Shell discoidal, sinistral ? sculptured ; peristome suddenly 

 expanded, plain; aperture with an inner rim, circular, and 

 deflected (upwards) at right angles to the plane of the shell. 

 Several examples have occurred. 



Fhilippia (lutea) Gray, has a multi-spiral operculum, and 

 the animal is like Trochus. (Philippi.) 



Paludestrina (lapidum) D'Orbigny part. Fresh waters of 

 South America. 



Shell conic, few-whorled, epidermis green ; aperture oblique, 

 peristome abrup^tly reflected ; operculum claw-like. The typical 

 sj^ecies appear to be 3felaniadce, but some small shells like 

 Eydrobia have been included in the genus. 



Phortjs, Montfort. Carrier-shell. 



Etymologij , phoreus, a carrier. 



Synonyms, Onustus, Humph., Xcnophorus, Fischer. 

 Examples, P. conchyliophorus, Born. P. corrugatus, PI, X., 

 Fig. 1. 



Shell trochiform, concave beneath ; whorls flat, 

 with foliaceous or stellated margins, to which shells, 

 stones, &c., are usually aflB:xed; aj)erture very 

 oblique, not pearly ; outer lip thin, much i)roduc3d 

 above, receding far beneath; operculum horny, im- 

 bricated, nucleus external, as in purpura and palii- 

 Fig. 108. domus, with the transverse scar seen through it. Fig. 

 108. (Museum Cuming.) 



Animal with an elongated (non-retractile?) jn'oboscis; ten- 

 tacles long and slender, with sessile eyes at their outer bases ; 

 sides plain ; foot narrow, elongated behind. — Adams. Related 

 to scalaria ? 



Most of the phori attach foreign substances to the margins of 

 their shells as they grow, iDarticular species afi'ecting stones, 

 whilst others prefer shells or corals. They are called " mineral- 

 ogists" and " conchologists," by collectors; P. Solaris and 

 P. indicus are nearly or quite free fi'oni these disguises. They 

 are said to frequent rough bottoms, and to scramble over the 

 ground, like the strombs, rather than glide evenly. 



Distribution, 9 species. West Indies, India, Malacca, Philip- 

 pines, China, and West America. 

 Fossil, 15 species. Chalk ? — Eocene — . Britain and France. 



