7i6 



INDEX 



Polythalamia, 74; 72 



Polytoma, 56; 20, 29, 30, 33, 40, 46; 



uvella, 23, 30 

 Polytricha, 109 

 Polyzoa, 606 ; 2 

 PoTtiatoceros, 263 ; 264, 267 ; triqueter, 



271 

 Pontobdella, 301 

 Porcellana, 415 ; 389 

 Pore plate of Radiolaria, 80 

 Pore-rhombs, 659 

 Pores, Collar, ^ee Collar pores ; Dorsal, 



see Dorsal pores; of Porifera, 117; 



Proboscis, see Proboscis pore ; 



Water, 658, see also Madreporite 

 Porifera, 117; i, 125 

 Porites, 191 ; 192 

 Porocytes, 118 

 Poromya, 579 

 Porthetria dispar, 490 

 Portuguese man-of-war, see Physalia 

 Posterior aorta, of Araneida, 530; of 



Astacus, 350; of Carcinus, 412; of 



Helix, 557; of Lamellibranchiata, 



580; of Scorpionidea, 522; of 



Sepia, 593 

 Posterior interradius of Echinoidea, 



647 

 Posterolateral arms of Plutei, 633 

 Posterolateral edge of Carcinus, 408 

 Postsegmental region of Crustacea, 



332 

 Preantennae, 318; 306 

 Preantennal somite, 306, 318, 425 

 Prebranchial zone, 669 

 Precheliceral somite (segment), 515; 



516 

 Precoxa, 336 

 Pregenital somite (segment) of Arach- 



nida.5i5;5i6 

 Preischiopodite (Preischium), 336 

 Prementum, 427 



Preoral lobe of Echinodermata, C32 

 Preoral region, of Annelida, 260 ; see 



also Prostomium; of Arthropoda, 



308; of Crustacea, 331, 332; of 



Echinodermata, see Preoral lobe ; 



of Enteropneusta, see Proboscis. 



See also Preseginental region, 



Preoral somites 

 Preoral somites, of Arachnida, 515; 



of Arthropoda, 309; of Chilopoda, 



420; of Crustacea, 332; of Ony- 



chophora, 319 



Presegmental region of Crustacea, 



332 

 Primary body cavity^ see Haemocoele 

 Primary embryo, 612 

 Prismatic layer, of Brachiopod shell, 



615 ; of Molluscan shell, 546 

 Probasipodite, 336 

 Proboscis, of Acarina, 534, 537; of 



Bonellia, 302 ; of Branchiura, 377 ; 



of Buccinum, 565 ; of Chaetopoda, 



264 ; of Enteropneusta, 662 ; of 



Hemiptera, 475 ; of Lepidoptera, 



487; of Nemertea, 233; of Panto- 



poda, 538, 539; of Rhyncho- 



bdellidae, 297 ; of Suctorial Cope- 



poda, 374, 375, 376 

 Proboscis cavity, of Balanoglossus, 



662, 668; of Chordata, 660 

 Proboscis complex of Balanoglossus, 



666 ; pore of Balanoglossus, 663 

 Proboscis sheath, of Buccinuvi, 565 ; 



of Nemertea, 233 ; of Rhyncho- 



bdellidae, 297 

 Probuds, 687 

 Procerebrum, 309, 340 n. 

 Procerodes lobata, 214 

 Prociliata (Opalinidae), 106; 26, 33 

 Proctodaeum, 130; of Arthropoda, 



314; of Crustacea, 344; of trocho- 



sphere, 284 

 Proctotrypidae, 502 

 Proepipodites, 336; 337, 348, 354, 



358, 364 



Progressive feeding, 498 n. 



Prolegs, 456, 490, 491, 500, SIC 



Proliferating region, of Syllidae, 278 ; 

 of Tapeworms (neck), 225, 227 



Proostracum, 600 



Propodite, 336 



Propolis, 504 



Prorodon, 107; teres, IIO 



Prosicula, 170 



Prosobranchiata, see Streptoneura 



Prosoma (" Cephalothorax" of Ar- 

 achnida), 308, 515, 521, 526, 530, 



533, 537 



Prosopyles, 120 



Prostate glands, of Oligochaeta, 287, 

 289, 291 ; of Sepia, 598 



Prostomium, of Annelida, 260; of 

 Chaetopoda*, 261, 264, 268, 272, 

 284, 291 ; of Echiuroidea*, 301, 

 302; of Hirudinea, 296; of Sipun- 

 culoidea, 304 



