Nigella, production of double flowers of, [408].
Nightingale, length of life of, [11], [36].
Nothnagel, on the cause of epilepsy, [314].
Nuclear plate, [187].
Nuclei, behaviour during fission, [118], [188];
connection of heredity with fusion of, [178];
influence of, [184];
influence in regeneration, [185];
nutrition of, [187].