PHYLLONOTUS. 225 



formed in rocks, wood, &c. is easily distinguished from any other 

 nearly allied genus by the curved, prominent, rib-like teeth. 

 Fig. 55, P. Dactylus ; 56. P. papyracea. 



PHOLEOBIUS. Leach. Part of the genus Saxicava, Auct. 



PHONEMUS. Montf. A genus of microscopic Foraminifera. 



PHORUS. Montf. Trochus agglutinans, Auct. Remarkable for 

 the adhesion of little pebbles, dead shells, &c. to the outer edge 

 of the whorls, which are taken up in the course of the growth of 

 the shell. From this circumstance they are called " Collectors, 

 Carriers, &c." Fig. 360. Recent species are brought from the 

 East and "West Indies ; fossil species are found in the Tertiary 

 beds. 



PHOS. Montf. Fam. Purpurifera? Lam. — Descr. Turrited, thick, 

 cancellated, varicose ; spire pointed, generally longer than the 

 aperture ; aperture rounded or oval ; outer lip having internal 

 ridges, with a sinus near the anterior termination ; columella 

 with an oblique fold ; canal short, forming externally a raised 

 varix. — Obs. The raised external surface of the canal, brings this 

 genus near to Buccinum, while, in general appearance, most of 

 the species more nearly resemble Murex. They have, however, 

 no true varices on the whorls, but merely raised bars. Fig. 416, 

 P. senticosus. 



PHYLLIDIANA. Lam. A family belonging to the first section 

 of the order Gasteropoda, Lam. The genera belonging to this 

 family may be distinguished as follows : 



1. Chiton. Composed of eight valves; valves contingent. 



Fig. 227. 



2. Chitonellus. The same, with the valves distant. Fig. 228. 



3. Patella. Conical, symmetrical. Fig. 229, 230. 



4. Patelloida Differing from Patella in the animal. Fig. 



231. 



5. Siphonaria. With a siphon on one side. Fig. 231*. 



6. Sctjtella, Siphon close to the side of the head. Fig. 



510, 511. 

 PHYLLONOTUS. Sw. A sub-genus of Murex, thus described : 

 ' ' Canal moderate; varices foliated, laciniated, compressed, or 



