IXD1C.X. 



611 



Pennatulacea, 179. 



Pentact, 91. 



Peptonephridia, 40. 



Peraclis, 406. 



Penuieniina, 31. 



Perforated shell, 361. 



Pericardia] glaii.], 322, 

 436 ; glands of Lain- 

 ellibranchs, 341. 



Pericardium of Gastro- 

 poda, 375, 377. 



Perichacna, 17. 



Perichaeta, 501, 506, 510, 



Pericolpa, 111, 165. 



Pericrypta, 165. 



Pericystie, 139. 



Peridiniuni, 34. 



Perigonimtis, 130. 



Pcrionyx. 510. 



Periostracum, 326. 



Peripalma, 165. 



Periphragella, 93. 



Periphvlla, 111, 165. 



Peripylaria, 21, 22. 



Perisark, 124. 



Perisiphonia, 133. 



Peristome, 40: of sliell, 

 361. 



Peristomium, 447. 



IVritrachelius, 284. 



Peritrieha, 50. 



Peritromus. 49. 



Perivisceral cavity of 

 Gastropoda, 375. 



Periwinkle, 3!'S. 



Perna, 336, 346. 



I'crneinal, 136. 



Peromedusae, 165. 



Peronia, 414, 416. 



Pcroniuni, 113. 



Perradial, 118. 



Persa, 135. 



Petachnxini, 135. 



Petalomonadina, 31. 



IVluloproctus, 488. 



Petalostoma, 539. 



Petasata, 135. 



Petasus, 135. 



Petricolidae, 348. 



Petrosia, 96. 



Petta, 486. 



Phacellae, 111. 



Phacellophora, 167. 



Phacodiseus, 23. 



Pliacotus, 32. 



Phacus, 31. 



Phaeoconchia, 24. 



Phaeocystina, 24. 



Phaeodaria, 23. 



Phaeodinia, 24. 



Phaeodium, 24. 



Phaeogromia, 24. 



Phaeosphaeria, 24. 



Phagorala, 210, 221. 



Phakellia, 96. 



Phalacroma, 35. 



Phalansterium, 33. 



Phanerocarpae, 159. 



Phanerocephala, 475. 



Phanerocodonic, 126. 



Phaneta. 395. 



Phascolion, 539. 



Phascolodon, 46. 



Phascolosoma, 536, 539. 



Phasianella, 395. 



Pheasant-shell, 395. 



Phellia, 188. 



Phelloderma. 96. 



Phenacia, 485. 



Pheronenia 92. 



Phertisa, 489. 



Phialidiuni. 134. 



Phialis, 134. 



Plnaliuni, 134. 



Philine, 3(32, 405, 406. 



Philodina, 299, 300, 304, 

 308. 



Philoinedusa, 188. 



Philomycus, 416. 



Philom'xis,421,441,446. 



Phloeodictyinae, 96. 



Pholadacea, 348. 



Pholadidea, 348. 



]'h..ladomya, 349. 



I'hulas, 327, 331, 344, 

 348. 



Pholoe, 478. 



Phoriospongia, 98. 



Phoronidea, 542. 



Phoronis, 451, 547. 



Phosphorescence of Ce- 

 phalopoda, 426 ; of 

 earthworm, 508 ; of 

 Polyzoa, 55t'.. 



Phractaspis, 23. 



Phractopelta, 23. 



Phragmocone, 425. 



Phreatothrix, 508. 



Phreodrilus, 509. 



Phreoryetes, 504, 505, 

 508." 



Phylartella, 566 



Phylactocarps, 126. 



Phylactolaemata, 567. 



Phyllactis, 187. 



Phyllaplysia, 407. 



Phyllastraea, 196. 



Phyllidia, 371. 412. 



Phyllirhoe, 374, 412. 



Phyllobotlirium, 259. 



Phyllohranclius, 413. 



Phyllochaetopterus, 484. 



Phyllocomu.s, 486. 

 Pliyllocotyle, 236. 

 Phyllocyst, 145. 

 Phyllodoce, 4ti7, 479 

 Phyllominyas, 187. 

 Phyllomitus, 31. 

 Phyllonella, 234. 

 Phyllophysa, 153. 

 Phyllorhiza, 168 

 Phyllospongia, 98. 

 Phymactis, 187. 

 Phymanthu.s, 187. 

 Phymastraea, 196. 

 Phymosoma, 536, 539. 

 Physa, 416. 

 Physalia, 156. 

 Physalidae, 154. 

 Physaloptera, 235. 

 Physarella, 17. 

 Physarum, 17. 

 Physcosoma, 536, 539. 

 Physematium, 21, 23. 

 Physogyra, 195. 

 Physouectae, 150. 

 Physophora, 150, 153. 

 Phytomastigoda. 32. 

 Pilema, 168. 

 Pileocejihalus, 59. 

 Pileolaria, 491. 

 Pileopsi.s, 398. 

 Pilidium, 269. 

 Piloehrota, 94. 

 Pilulina, 13. 

 Pinaciophora, 19. 

 Piiiauouystis. 19. 

 Pinna, 327, 336, 338, 341, 



346. 



Pinnoctopus, 446. 

 Pinulus, 92. 

 Pionosyllis, 476. 

 Pirula, 400. 

 Piscicola, 513, 526 

 Pisidiuni, 341, 347. 

 Pista, 485. 

 Pistilluni, 151 

 Placinastivlhi, 94. 

 Placocyathus. 194. 

 Placophora, 387. 

 Placortis, 95. 

 Placospungia, 94. 

 Placostegus, 491. 

 Placotrochus, 194. 

 Placuna, 345. 

 Placnnclla, 234. 

 Plagiochaeta, 511. 

 Plagiopogon, 46. 

 Plagiostomum, 214, 220. 

 Plagiotoma, 48. 

 Plagoniscus, 23. 

 Plagonium, 23. 

 Plakina, 95. 



