Biorhiza, length of life of imago of, [50].
Birds, length of life of, [11], [36];
factors in duration of life of, [12].
Blackbird, length of life of, [6], [11], [36].
Blaps, length of life of imago of, [47], [48].
Blastogenic characters, [412].
Blochmann, on polar bodies, [349].
Blow-flies, length of larval life of, [15].
Boar, length of life of, [14].
Bombinator igneus, nature of ovum of, [125].