INDEX. 295 



N 



Na'is, structure and habitat of the, ii. 152, 153 

 Naphtha, manufacture of, i. 120 



uses to which it is applied, i. 120 



sources of, in various parts of the world, i. 126 



naphtha procured by the distillation of petroleum, i. 127 

 Napthalin, production of, i. 127 



Narcotics, exciting, known to almost all people, however savage, i. 427 

 Navicula, structure of, i. 198 

 Naviculae, spontaneous locomotion of, L 202 

 Nebulae, spectra of various, i. 158-160, 163 



constitution of the, i. 163 



probable existence of primordial nebulous matter according to the 



theories of Sir W. Herschel and La Place, i. 164 

 Nectria, characters of the genus, i. 295 

 Nectria Peziza, structure of, i. 295 



Nematoid entoza, structure and mode of reproduction of, ii. 146 

 Nemertes gigas, or great band worm, nervous system of, ii. 158 

 Neotteae, characters of the British tribe of, i. 397, 398 

 Neottia Nidus-avis, structure and mode of reproduction of, L 400 

 Nephrolepis tuberosa, characters and habitat of, i. 348 

 Nereis, structure of, ii. 157 



Nereis diversicolor, mode of reproduction of, ii. 160 

 Nereocystis Lutkeana, structure and habitat of, i. 249 

 Nerve-force of animals, ii. 4, 6 



chemical powers generated by, ii. 6 

 Nerves of animals, structure and functions of, ii. 5 



electric currents in the, ii. 7 



structure and functions of the brain and spinal cord, ii. 8 



the nervous systems of the higher and lower animals, ii. 9-11 

 Nervous system of animals, ii. 5 

 Nickel, i. 4, 5 



crystals of, formed artificially by electricity, L 74 



effect of heat on the magnetism of, i. 77 



atomic weight of, compared with that of hydrogen, i. 100 

 Nidulariacei, characters of the order of, i. 272, 273 



structure and mode of reproduction of, i. 273 



habitat of, i. 273 



Nitella flexilis, structure and mode of reproduction of, i. 312 

 Nitophyllum, structure and fronds of, i. 238, 239 



