300 INDEX. 



Penicillium glaucum : its polymorphous character, i. 287 

 in the yeast of beer, i. 288 

 its production of acetic fermentation, i. 288 

 Pennatula phosphorea, structure and habitat of, ii. 128 



modes of reproduction of, ii. 129 



Pennatulidse, or sea-pens, structure, habitat, and mode of reproduc- 

 tion of, ii. 128, 129 

 Pentacrinites, structure of, ii. 175 



Pentacrinus caput-Medusse, structure and habitat of, ii. 175 

 Pentacrinus Europseus, structure of, and change to acomatula, ii. 176 

 Peppermint, absorption of radiant heat by the perfume of, i. 44 

 Peranemese, or Woodsieae, characters of the group, i. 350 

 Perfumes of flowers and plants, absorption of radiant heat by the, i. 44 

 weight of the perfumes, i. 45 

 chemical combinations forming, i. 97 

 Peridinium, structure and habitat of, ii. 72 



scarlet colour it gives to the sea, ii. 72, 75 

 mode of propagation of, ii. 75 

 Perisporacei, structure and habitat of, i. 295 

 Periwinkle, tongue of, ii. 239 



Peronospora infestans, its destruction of the potato, i. 284 

 structure and mode of working, i. 284, 285 

 its effects on the branches and wood of trees, i. 285 

 PerophoraListeri, structure, habitat, and development of, ii. 222, 223 



larva of, ii. 224 



Petroleum, enormous quantities of, in North America, i. 126 

 the Babylonian petroleum fountains of Is, i. 126 

 geological formation in which it occurs, i. 126 

 dangers of petroleum wells, i. 127 



substances yielded by it on destructive distillation, i. 127 

 Peyssonelia, habitat of, i. 237 



Peziza aurantia, cells of staff-shaped particles of, i. 291 

 Peziza elegans, beauty and habitat of, i. 291 

 Peziza vesiculosa, force of its ejection of its sporidia, i. 292 

 Pezizse, structure and habitat of the genus, i. 290, 291 

 fructification of, i. 291 



eel-shaped particles or antherozoids of, i. 292 

 force with which many of them eject their sporidia, i. 292 

 Phacopsis, organs of reproduction of, i. 307 

 Phalloidei, structure of, i. 268 

 Phallus Mokusin, a food of the Chinese, i. 268 

 Phascei, characters of, i. 329 



