INDEX. 323 



Perichffita, naturalized near Nice, 106 

 Perrier, worms surviving long immersion, 13 



on tlie calciferous glands, 44 



on the action of the pharynx, 56 



on the burrowing power of worms, 99 



on naturalized worms, 106 



on worms killed by acetic acid, 159 



on the gizzards of worms, 246, 249 



Petioles of Clematis, 77 



of the ash, 79 



Pharynx, action of, 56 



Pike, stupidity of, 94 



Pine-leaves used in plugging up burrows, 58, 70 



lining burrows, 112 



Pipes, formation of, in the chalk, 187 

 Playfair on Denudation, 290 

 Ploughed fields, old, 292 

 Plugging, up of the burrows, 58 



use of the process, 62 



Prehension, power of, by worms, 56 



Qualities, mental, of worms, 34 



Ramsay, Mr., on the sinking of a pavement undermined by 

 worms, 192 



on Denudation, 231 



Remains, ancient, buried by worms, 176 



Rhododendron leaves, 69 



Richthofen on dust deposits in China, 237 



Robiuia, petioles of, 81 



Rocks, disintegration of, aided by worms, 240 



■ triturated in the gizzards of worms, 249 



Rolling down of dry castings, 275 



Romanes, Mr., on the intelligence of animals, 95 



