272 INDEX. 



Digestion, chemical powers causing, ii. 4 

 Dimorphism, contrasted with isomorphism, ii. 99 

 Diphyidse, structure and habitat of the, ii. 103 

 Diplaziese, characters of the group, i. 352 

 Diplazium, structure and fructification of, i. 352 

 Distillation, ordinary, i. 117 



destructive, i. 117 

 of coal, i. 117 



Distomata, characters of the, ii. 146 

 Dracaena Draco, or dragon tree of Teneriffe, i. 387 

 Drummond's light, how produced, i. 30 



the continuous spectra of, i. 132 

 Dry rot in wood, cause of, i. 266 



on various substances, i. 285 

 Dulses, red, i. 235 



Dumontia filiformis, structure qf, i. 235 

 D'Urvillea, structure, fructification, and habitat of, i. 256 

 Dyes obtained from aniline, i. 122-124 



vegetable dyes, i. 124 



mordants for cotton when dyed, i. 125 



effects of electricity and the east wind on the process of dyeing, 

 i. 126 



obtained from preparations of petroleum, i. 127 



obtained from lichens, i. 303 



blue dye obtained from some club mosses, i. 374 



E 



Ear-shell, structure of the, ii. 234 



Earth, quantity of heat which would be generated if it were arrested in 



its orbit, i. 27 



and if it struck the sun, i. 28 

 Earth light, causes of, i. 68 



Eurth-worm, structure and food of the, ii. 151, 152 

 Echinodermata asteroidea, structure, mode of reproduction, and habitat 



of, ii. 169-174 

 Echinodermata crino'idea, or stone-lilies, structure, habitat, and mode of 



reproduction of, ii, 175, 176 

 fossil remains of, ii. 175 

 Echinodermata Echinoi'dea, structure and mode of reproduction of, ii. 



177-182 



