528 



MOLLUSCA — BRACHIOPOD A 



Patelliform shell in various genera, 19 



Faterina, 509, 510, 511 



Patinella, radula, 227 



Patula, 297, 298, 318-338, 340, 44^ 



Paxillus. 413 



Pearl oysters, 100 



Pecten, 4-46, 450, 4oO ; organs of toucb, 

 178 ; ocelli, 191 ; flight, 192 ; nervous 

 system, 206 ; genital orifice, 242 ; 

 ligament, 271 



Pectinodonta, 405 ; radula, 227 



Pectunculus, 448 



Pedicularia, 75, 419 ; radula, 224 



Pedinogyra, 319, 322, 442 



Pedipes, 18, 199, 439, 439 



Pedum, 450 



Pelagic Mollusca, 360 



Pelecypoda, 7, 445 ; development, 145 ; 

 generative organs, 145; branchiae, 

 166-169 ; organs of touch, 178 ; eyes, 

 189 f.; foot, 201 ; nervous system, 205 



Pella, 333 



Pellicula, 352, 442 



Peltoceras, 399 



Pentadaclylus, 4^3 



Peraclis, 436 



Pereiraea, 418 



Perideris, 328-330, US ■ 



Periodicity in breeding, 129 



Periophthalmus, 187 



Periostracum, 275 



Periploma, 459 



Perispliinctes, 399 



PerissodoHta, 418 



Perissolax, 4^4 



Peristernia, 4^4 



Perna, 449 ; ligament, 271 



Pernostrea, 449 



Peronaeus, 358, 442 



Peronia, 443 



Perrieria, 319, 44^ 



Perrinia, 408 



Persicida, 425 



Persona { = Distortio) , 420 



Petenia, 353, 440 



Petersia, 4^0 



Petraeus, 295, 331, 44^ 



Petricola, 454 



Phacellopleura, 403 



Phanerophthalmus, 430 



Phaneta, 408 



Phania, 312, 441 



Pharella, 457 



Pharus, 457 



Pharynx, 210 



Phasianella, 409 



Phasis, 333 



Phenomena of distribution, 362 



Philine, 245, 428, 430; protective 

 coloration, 73 ; radula, 229, 230 



Philomycus, 245, 318, 440 



Philonexis, 138 



Philopotamis, 304, 417 



Phoenicohius, 315, 441 



Pholadacea, 457 



Pholadidea, 457 



Pholadomya, 459 



Pholas, 245, 274, 447, 457; in fresh 



water, 15 

 Phos, 424 

 Photinula, 4O8 

 Phragmophora, 386 

 Phyllidia, 434 ; breathing organs, 159 

 Phyllirrhoe, 360, 428, 433 

 Phyllobranchus, 432 

 PhijUoceras, 398, 398 ; suture, 396 

 Phylloteuthis, 390 

 Physa, 439 ; aestivating out of water, 



27 ; spinning threads, 29 ; sudden 



appearance, 46 ; osphradium, 195 ; 



nervous system, 205 ; radula, 235 ; 



P. hypnorurriy 23, 27 

 Pileolus, 410 

 Pileopsis, 76 

 Piloceras, 394 

 Pinaxia, 4^3 

 Pineria, 442 

 Pinna, 449 ; shell, 254 

 Pinnoctopus, 385 

 Pinnotheres, 62 

 Pinoceras, 398 

 Pirena, 417 

 Pirenella, 4I6 

 Piropsis, 424 

 Pirida — see Pyrula 

 Pisania, 424 

 Pisidium, 453 ; smell, 195 ; ova, 146 ; 



P. pusillum, distribution, 282 

 Pitys, 327 



Placohranchus, 432 

 Placostylus, 322, 323-325, 359, 442; 



radula, 233 

 Placuna, 448; P. placenta used for 



windows, 101 

 Placunanomia, 448 

 Placunopsis, 448 

 Plagioptycha, 347-351, 44I 

 Plagioptychus, 456 

 Planaxis, 417 



Planispira, 311, 312, 319, 441 

 Planorhis, 27, 247, 439 ; monstrosity, 



93 ; eye, 181 ; P. alhus, distribution, 



282 

 Platyceras, 76, 412 

 Platydoris, 434 

 Platypoda, 4II 

 Platyschisma, 413 

 Plaxiphora, 403 

 Plecochilus, 442 

 Plecotrema, 439 

 Plectamhonites, 505 

 Plectomi/a, 459 



Plectopylis, 303, 305, 314, 316 ; aper- 

 ture, 63 



