INDEX 



419 



Psettichthys melanostictus, 333 

 Pseudomonas radicicola, 139 

 Pseudotsuga mucronata, 244 

 Psoloessa delicatula, 265 

 Psolus chitinoides, 330 

 Psoraloa, argophylla, 272 



tenuifloi'a, 247, 272 

 Pterastcr tesselatus, 331 

 Pteropods, 319 

 Purpurea, 326 

 Purshia, 292 

 Pyrameis atlanta, 203 



cardui, 203 

 Pyramidula striatella, 231 



Quadrats, of droppings, 196 



of trapping, 356 

 Quail, 105, 175, 185 

 Quantitative methods, 355, 358 

 Quasi-organism, 22 

 Quercus marilandica, 279 



stellata, 279 

 Quetico Park, 132 

 Quill back, 300 



Rabbit, 114, 123, 133, 193 



common, 125 



curve, 177, 179 



cycle, 177-180 



grassland, 257, 264, 285, 289, 290 



population, 187 



problem, 125 



snowshoe, 112, 192, 194, 195 



swamp, 280 

 Raccoons, 119 

 Radiolaria, 140, 319 

 Ranunculus, 288 

 Raptors, 73, 134 

 Rat, 108 



black, 166 



Norway, 166 



rice, 280 



wood, 72 

 swamp, 280 

 Rat-tailed fish, 332 

 Rattlesnake, 274, 285, 290 



Pacific, 290 



prairie, 256 



retreats of, 285 



swamp, 276, 274 



Ravens, 112 



Reaction, 68, 4, 69-102, 235, 236, 248 

 air, 91-94 



carbon dioxide and oxygen, 92 

 climate, 93 



humidity, temperature and wind, 92 

 light, 91, 92 



produced by man, 93, 94 

 definition and nature, 68, 69 

 kinds, 71 

 land, 71-91 



relation to life forms, 69, 70 

 role, 70-71 

 soil, 72 



accumulation, 72-75 



shells and concretions, 75 

 adding organic matter, 78, 79 

 air content, 89 

 compacting particles, 86 

 decreasing plant nutrients, 88, 89 

 decreasing water content, 88 

 digging and burrowing, 80-84 

 disturbing, 79, 80 

 formation, 72-75 

 increasing water content, 87, 88 

 profile, 90, 91 



returning plant nutrients, 88 

 slipping and sliding, 77, 78 

 surface disturbances, 84-86 

 terms of acids and toxins, 89, 90 

 water-borne detritus, 76, 77 

 weathering, 75, 76 

 wind-borne material, 76 

 water, 94-102 

 fresh, 94, 95-98 



pelagic and deep benthic areas, 

 100, 102 

 bottom in deep water, 101, 102 

 medium, 100, 101 

 sea, 99-102 



small lakes and ponds, 95-97 

 accumulation and decomposition, 



95, 96 

 medium, 96, 97 

 streams, 97, 98 

 sluggish-water, 98 

 swift-water, 98 

 tidal areas, 99, 100 

 belt between mean high and low 



tide, 99 

 littoral benthic belt, 99-100 



