Elementary Biulogy. 



PEL 



Pelvic girdle, 305 



Penicillium, mycelium of, 93 ; life- 

 history of, 93 ; reproductive 

 organs of, 96 ; compared with 

 Fucus, 97 



Pepsin, 278, 337 



Periblem, 173 



Peri derm, 181 



Perineurium, 314 



Perisarc, 221 



Peristalsis, 277 



Peritoneum, 272 



Phalanges, 305, 306 



Phelloderm, 181 



Phellogen, 181, 182 



Phloem, 118,134, 147, 179 



Phosphorescence in the animal, 344 ; 

 in the plant, 209 



Phosphorus, origin of and import- 

 ance of, to the plant, 192 



Phyllotaxis, 160, 185 



Phylogeny, 53 



Physics, definition of, 4 



Physiology of protoplasm, 31 ; of 

 the plant, 189, 196 ; of the animal, 



335 



Pia mater, 313 



Pineal gland, 308 



Pituitary body, 308 



Placenta, 123 



Planula, 231 



Plasmodium, 59 



Plasmolysis, 200 



Plerome, 173 



Pleuron, 292 



Pliny, 346 



Polar body, 328 



Pollen grains, structure of, 162, 166 ; 

 development of, 169 



Polytrichum, life-history of, 101 ; 

 structure of the sporophyte of, 

 108 ; reproductive organs of, 104 ; 

 structure of the gamophyte of, 

 101 ; structure of the embryo of, 

 ic8 ; compared with Penicillium, 

 112 



Portal circulation, 288 



Postcaval vein, 291 



Potassium, origin of and importance 

 to the plant of, 193 



Potential energy, 12 



Praefoliation, 121 



Precaval vein, 291 



Premaxilla, 303 



RAN 



Pressure, effect of, on organisms, 44 



Proctodaeum, 262 



Prosencephalon, 308 



Prosenchyma, 149 



Protamaoa, life-history of, 55 



Proteids, 26 



Protista, 55, 63 



Protococcus, life-history of, 69 



Protomyxa, life-history of, 57 



Proton ema, 104 

 I Protophyta, 63 



Protoplasm, morphology of, 29 ; 

 varieties of, 38 ; composition of, 

 25 ; physiology of, 31 



Protozoa, 63 



Kseudopodium, 33 



Pteris, structure of the sporangium 

 o f , 122 ; structure of the leaves 

 of, 121 ; germination of the spores 

 of, 126 ; structure of the rhizome 

 of, 114 ; life-history of, 113 ; 

 structure of the roots of, 120; 

 structure and development of the 

 embryo of, 129 ; ovaria of, 128 ; 

 thallusof, 126 ; spermariaof, 127 ; 

 summary of the more important 

 conclusions in regard to, 130 



Pterygoid, 304 



Ptya'lin, 337 



Pubis, 306 



Pulmo-cutaneous artery, 289 



Pulmonary vein, 289 



Punctum vegetation is, 212 



Pupil of the eye, 322 



RADIUS, 305 

 I Kana, intestine of, 277 ; teeth 



of, 267, 270 ; stomach of, 277 ; 

 tongue of, 271 ; skull of, 301 ; re- 

 spiratory system of, 291 ; circu- 

 latory system of, 282 ; alimentary 

 canal of, 265, 272 ; reproductive 

 system of, 326; blood of, 282; 

 heart of, 285 ; external characters 

 of, 265 ; renal system of, 294 ; 

 fore limb of, 305 ; deve-opment of 

 the brain of, 332 ; development of 

 the embryo of, 329 ; metamor- 

 phosis of, 332 ; sperms of, 327 ; 

 ova of, 328 ; spermarium of, 326 ; 

 ovarium of, 326 ; nervous system 

 of, 307 

 Ranunculus, stem of, 178 ; leaf of, 



