254 MANUAL OF THE MOLLtJSCA. 



Shell usually sinistral, flat, or coucave above ; aperture 

 quadrangular. 



Platy stoma (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. 



Philippia (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 abruptly reflected ; operculum claw-like. The typical 

 species appear to be Melaniadce, but some small shells like 

 Hydrobia have been included in the genus. 



Phortjs, Montfort. Carrier-shell. 



Etymology, phoreus, a carrier. 



Synonyms, Onustus, Humph., Xenophorus, Fischer. 

 Examples, P. conchy liophorus, 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 affixed; aperture very 

 oblique, not pearly ; outer lip thin, much producjd 

 above, receding far beneath; operculum horny, im- 

 bricated, nucleus external, as in purpmra and pala^ 

 Fig. 108. (^Q^iig^ with the transverse scar seen through it, Fig. 

 108. (Museum Cuming.) 



Animal with an elongated (non-retractile?) proboscis; ten- 

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

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

 to scalaria ? 



Most of the phori attach foreign substances to the margins of 

 their shells as they grow, particular 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 from 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. 



