INDEX 



417 



Panicum, scribnerianum, 270 



virgatum, 278 

 Panorpa venosa, 231 

 Paphia, 332 



staminea, 333 

 Paramecium, 140 

 Parasite, 45-46, 165 

 animal, 45 

 bacterial, 45 

 external, 45, 46 

 insect, 46 

 trematode, 301 

 types, 45 

 Parasitism, 143 

 Parasitoidism, 144 

 Parkinsonia, 283 

 Parks, 172 



Paspalum plicatulum, 278 

 Passer domesticus, 213 

 Pawing, 79, 85 

 Pecking, 85 

 Peck order, 161 



Pecten groenlandicus community, 345 

 Pectens, 331, 332 

 Pectinaria, 181, 334 



koreni, 182 

 Pectinatella, 52 

 Pelagic, 15 

 areas, 100-102 

 climaxes, 18 



communities, 29, 314-322 

 eggs, 35 

 Pelican, 153-154 

 Pellet, 134 



counts, 74 

 Pentstemon, 261, 288 

 Perdominants, 243 

 Peregrine falcon, 190 

 Perennial forbs, 261 

 Peridinia, 315 

 Period of flowering, 41 

 Perla, 308, 310 

 Permeant, 242 

 Perognathus californicus, 290 

 Peromyscus, 169 



maniculatus artemisiae. 169 

 maniculatus nebrascensis, 259 

 Pctalostemon, 279 

 candidus, 272 

 purpureus, 272 



Petrel, 170 



Pewee, 135 



Phacoides tenuisculptus, 339 



Phenacobius mirabilis, 308 



Phenologj^ 35 



Phialidium gregarium, 315 



Phlibostroma quadrimaculatum, 265 



Phlox pilosa, 272 



Phocaena phocaena, 316 



Phoebe, 86, 135 



Phosphorus, 73 



Phrynosoma cornutum, 267 



Phyllospadix, 25 



Phymata erosa fasciata, 275 



Physiognomy, 229 



grassland, 251 

 Physiologic orientation, 228 

 Physiological types, 323 

 Phytobiocenose, 7 

 Phytoplankton, 14, 96 

 Picea engelmanni, 244 

 Pied-billed grebe, 223 

 Pigeons, 214, 226 

 Pilchard, 201 

 Pilot fish, 319 

 Pinus, ponderosa, 244 



sabiniana, 288 

 Pioneer family, 247 

 Pipe fish, 340 

 Pipit (Anthus), 135, 257 



Sprague's, 252 

 Pisaster ochraceus, 326, 328 

 Pisidium sp., 300 

 Pituophis, 257 



catenifer, 290 



sayi, 265, 274 

 Plaice, 336 

 Plains, 120 



Plains gartersnake, 265 

 Plains weasel, 265 

 Plankton, 14, 91, 301, 307, 314, 321 



animals, 91 



communities, 315-316 

 fresh-water, 301 



marine, 315, 316 



organisms, 303 

 Plants, 49, 77. 180 



active agents, 136-138 



aggregations, 57, 58 



community relation, 43, 44 



