Döderlein, on tailless cats, [390], [428], [430].
Dragon-flies, length of larval life of, [15];
length of life of imago, [17], [40].
Dryophanta, length of life of summer generation of, [49];
of winter generation, [50].
du Bois Reymond, on the transmission of acquired characters, [82], [390], [422].
Duration of life governed by needs of species, [9].
Düsing, on origin of sex, [239], [241].
Eagles, length of life of, [11], [37];
weight of, [14].