Index 



471 



PLASTIDULES, plast'idiils (G. plastos, 



formed [diminutive ending] ) 91 



PLASTOCHONDRIA, plast'okon'drea 



(G. plastos + chondros, cartilage) .. 91 

 PLASTOCONTS, plas'toconts (G. 



plastos, formed ) 91 



PLASTOSOMES, plast'osoms (G. plas- 

 tos + soma) 91 



PLATO, pla'to 377 



PL A TYHELMINTHES, plat'yhelmin'- 

 thez (G. platys, flat + helmins, a 



worm) 205, 286, 430 



PLATYHELMINTHES AND NEMA- 

 THELMINTHES, plat'ihelmin'thez 

 (G. platys, flat + helmins, a worm) 



286, 311 



Flat-worms 286 



Turbellaria 286 



Excretory system 287 



External appearance 287 



Muscular system 288 



Nervous system 288 



Regeneration 289 



Reproductive system 288 



Trematoda 289 



Infections by 291 



Life cycle of 289 



Cestoda 294 



Eggs of 302 



Infections by 296 



Life cycle of 294 



Types of 291 



Nematoda ( threadworms ) 299 



Ascaris 300 



Digestive system 300 



Eggs of 302 



Excretory system 301 



Infections by 301 



Intermediate and Uncertain Forms. 307 



Nervous system 301 



Parasitic 304, 305 



Reproductive system 301 



PLECOPTERA, plekop'tera (G. plekein 



twisted + pteron, wing) 426 



An order of Persoidea. 

 PLECTOPTERA, plektop'tera (G. 



plekein + pteron) 426 



An order of Ephemeroidea. 

 FLEROME, pler'om (G. pleroma, a fill- 

 ing up ) 229 



PLEURA, plew'rah (G. pleura, rib, 



side) 316 



PLEURITES 337 



PLEUROBRANCHS, plor'obranks (G. 



pleura, a side -f- brangchia, gills).. 322 

 PLEU RO COCCUS, pluro'kok'us (G. 



pleura; L. coccus, a berry) 186 



PLEXUS, pleks'us (L. interweaving) . 67 



Nerve 68 



PLICAE 46 



PLINY THE ELDER 377 



PNEUMATOPHORE, numat'ofor (G. 

 pneuma, air + pherein, to bear) . . . .256 



PNEUMOGASTRIC, numdgas'trik (G. 



pneuma + L. gaster, stomach) 68 



PODICAL PLATE, pod'ikl (L. podex, 



rump ) , definition of ; 338 



PODOBRANCHS, po'dobranks (G. 



pous + brangchia, gills ) , definition 



of 322 



PODOPHYRA, podo'flra (G. pous, 



foot + phyro, to mix) 156 



POECILOPODA, pesilop'oda (G. poelci- 



los, many-colored + pous, foot) .424, 432 

 POISON' FANG— 



Gland 46, 362 



POLAR BODIES, polar (G. polas, 



pivot ) , definition of , 101 



POLARITY, definition of 289 



POLAR NUCLEI, definition of 245 



POLE-CELLS, definition of 200 



POLLEN, pol'len (L. pollen, fine flour). 227 



Sac, definition of 244 



Tube 240 



POLLEX, polTeks (L. pollex, thumb) . 76 

 POLLINATION (L. pollen, fine flour), 



definition of 239 



POLYCHAETA, polike'ta (G. polys, 



many + chaite, mane) 284, 423 



A sub-class of Annelida. 

 POLY CLAD ID A, poliklad'ida (G. 



poly dados, many branched) 422 



An order of Turbellaria. 

 POLYEMBRYONY, pol'iem'brioni (G. 



polys, many + embryon, a fetus) . . .346 

 POLYGENETIC, polijene'tik), defini- 

 tion of 404 



POLYGNOTUS (G. polys, many + 



notus, known ) 347 



POLYGORDIU S, poligor'dius (G. 



polys, many + gordios, gordius) .284, 428 



Appendiculatus 281 



POLYMORPHIC, polymor'fic (G. polys, 



many + morphe, form), definition 



of 256 



POLYMORPHISM, polimor'fizm (G. 



polys + morphe) 256 



POLYP, pol'ip (L. polypus, a polyp) .252 

 POLYPIDE, pol'yped (G. polys, many 



+ pes, foot) , definition of 311 



POLYPHYLETIC, polifilet'ik (G. polys, 



many + pliylon, race), definition of. 404 



POLYPINUM 156 



POLYPLACOPHORA, poliplakof'ora 



(G. polys, many + plax, a tablet) . .423 

 An order of Amphineura. 

 POLYTRICHUM COMMUNE, pGl'ytii- 



kum eomunay (G. polys, many + 



thrix, hair) .218 



POND SCUM, definition of 805 



POND SNAIL 290 



PORES, EXCRETORY (G. poros) . . . .207 

 PORIFERA, porifVra (G. poros, chan- 

 nel + L. fcrrc, to boar) 42D 



