Cow black-bird, 27; his favorite perch; old dame's theory, 28; an unwelcome intruder, 30; a prowling foe, 31. Cow-bird: --Ravenous young parasite, 31; a clamoring lubber, 37; "Black Douglas" of the bird-home, 38; selected victims, 39; distribution of its eggs; vicious habits, 40; egg-laying intervals; demoralizing conditions; American species an improvement, 41; survival of the fittest, 42; balance of power, 44; outwitted, 51; massing for migration, 52. "Cow-spit," 80. Cross-fertilization, 115, 122, 178, 189, 194. "Cuckoo-spit," 80. Cuckoos: --Poetic misnomer, 23; outrage on maternal affection; yellow-billed; black-billed; imagination versus facts, 25; bad workmanship of nest, 26; its stammering cry, 27; manner of depositing its eggs; handling the egg with her bill, 33; short period of incubation; voracious appetite of the young; aggressive selfishness, 34; the tragedy of the nest, 35; manner of disposing of its nest-mates, 36. _Cypripedium acaule_, moccasin-flower; ladies'-slipper; Venus's-slipper, 205. Darwin: --Process of anatomical evolution, 35; theory of cross-fertilization, 105; inspired insight, 115; his disciples, 116; experiments with pollen, 126; weakness of self-fertilizing flowers, 144; triumphant revelation, 171; reaffirming Sprengel's theory, 178; a chosen interpreter, 181; dependence on insects, 183; revealing the hidden treasure, 185; foretelling the manner of cross-fertilization, 189; description of the cross-fertilization, 209; bees as implied fertilizers, 212; truth of his belief, 220. Darning-needle, dragon-fly (_Libellulidae_), 156; his dainty morsel, 160. Delpino, a follower of Darwin, 116. _Desmodium_, its hospitable welcome, 118. Devil's-bit (_Chamaelirium luteum_), 133. Digger wasp, its color and wire-like waist, 72; manner of working, 74; covering its tracks; opening the tomb, 76; living food for the young grub, 77; its remarkable carrying power, 78. Dogbane (Apocynum), its fragrant, bell-shaped flowers, 236; trapping moths, 237. Dogwood, 5.