INDEX 



277 



Pinnules, 180 

 Pisaster, 182 

 Piscicola, 156, 157 

 Pisidium, 187, 201 

 Placobdella, 156, 157 

 Placophora, 201 

 Plakina, 87 

 Planaria, 109, 125 

 Planocera, 125 

 Planorbis, 193, 201 

 Planula, 91, 95, 99, 257 

 Plasmic products, 60, 64 

 Plasmodiophora brassicae, 43 

 Plasmodium, 45 

 Plasmodroma, 29, 56 

 Plathelminthes, 105, 125, 257 

 Platvdorina, 66 

 Platypoda, 196 

 Plecoptera, 251 

 Pleodorina, 56 

 Plerocercoid, 120 

 Pleura, 241 



Pleurobrachia, 101, 103 

 Pleurocera, 196, 201 

 Pleuroxus, 222 

 Plumatella, 160, 164 

 Plumularia, 102 

 Pluteus, 176 

 Pneumatophore, 93 

 Pneumonoeces, 126 

 Podomeres, 206 

 Podophrya, 54, 58 

 Poison glands, 227, 233 

 Polar capsules, 48 

 Polian vesicle, 172, 176, 178 

 Polyarthra, 143 

 Polychaeta, 147, 148, 157 

 Polycladidea, 110, 122 

 Polyembryony, 17, 205 

 Polygordius, 156, 158 



development, 156 

 Polygyra, 197, 201 

 Polymastigina, 56 

 Polymorphism, 93 

 Polyopisthocotylca, 113, 125 

 Polyp, 88, 89 

 Polyphemus, 211, 222 

 Polypus, 201 

 Polvstoma, 113, 125 



Polystomella, 37 

 Polythalmia, 42 

 Polyxenus, 233, 234 

 Polyzoa, 159, 164 

 Pompholyx, 143 

 Porcellio, 222, 223 

 Porifera, 81, 86 



morphological types, 82 



phylogeny, 256 

 Porites, 103 

 Porocephalus, 230, 234 

 Portuguese man-of-war, 88, 93 

 Postabdomen, 212, 227 

 Posterior ganglion, 170 

 Postgenae. 239 

 Prawns, 216 

 Preabdomen, 227 

 Predaceous habit, 24 

 Primitive segments, 151 

 Primitive vs. degenerate, 3 

 Primordial germ cells, 11 

 Priority, law of, 3 

 Pristina, 157 

 Proales, 143 

 Proboscis, Acanthocephala, 134 



Gasteropoda, 194 



leech, 155 



Nemertinea, 123 



snail, 194 

 Proboscis receptacle, 135 

 Proboscis sheath, 123 

 Prochordates, 1, 259 

 Proctodaeum, 71 

 Proetus, 209 

 Proglottids, 116 

 Promitosis, 26 

 Prorhynchus, 125 

 Prorodon, 52, 57 

 Prosobranchia, 195, 201 

 Prosopyles, 83 

 Prostomata, 125 

 Prostomium, 147, 206, 216 

 Protandrous, 84 

 Proteocephalus, 122, 126 

 Proteomyxa, 57 

 Proterosjjongia, 82, 257 

 Prothorax, 241 

 Protobranchia, 201 

 Protodrilus, 156, 15S 



