S Sable, [190] Saffron finch, [244] Sainfoin, [267] Salamander, [217], [219], [221] Salix alba, [118] S. pentandra, [118] Sandgrouse, [204], [351] Sandpipers, [185], [190] Sassaby, [363] Satyridæ, [205] Scatliff, H. P., [91]-3 Scatliff strain, [91] Scaup, [290] Schmankewitsch, [156] “Science,” [166] Sciuropterus volucella, [243] Scops giu, [101] Scops owl, American, [44] ——, Indian, [101] Scoter, [249] Seal, [190], [191] Sea-urchin, [149] Seaweed, [263] Sebright, Sir John, [63] Secondary sexual characters, [298] Segregation, [369] —— of gametes, [143]-5 Selous, Edmund, [308] —— F. C., [192], [195], [197], [203] Sematic colours, [173] Sesia fuciformis, [178] Sexual dimorphism, [51], [297]-344 Sexual selection, theory of, [299]-321 Shaheen, [251] Shamrock, [274] Sheathbill, [191] Sheep, [95], [266], [267], [283], [357], [372] Sheldrake, [109], [129] Shikra, [235], [236] Shoveler, [290] Shrew, [180], [216] Sidgwick, [28] Sidney, [5], [49] Sika deer, [120] Silver-washed fritillary butterfly, [103] Siskin, [127], [244] Skua, Arctic, [44], [362] Skua-gull, [191] Skunk, [186], [217], [221] Skylark, [315] Slug, [49], [185] Smith, Adam, [28] Snake, [185], [197], [198], [217], [220], [223]-6, [247], [356] Snap-dragon, [268], [272] Snipe, [69], [327] Sodium sulphate, [151] Somatic variations, [106]-10 “Some Indian Friends and Acquaintances,” [225], [358] Sorrel, [274] Sparrow, [213], [241], [341], [342] —— Java, [99], [100] Sparrow-hawk, [235], [243] Spatula clypeata, [290] Spavin, [332] “Species and Varieties,” [69], [77], [84], [87], [118] Species, definition of, [89] Species, elementary, [77], [78], [87]-9 Spencer, [3], [15], [16], [28], [38], [151] Spider, [269], [272] Sporæginthus amandava, [311] Sports, [41], [43], [66], [75], [85], [135] Squirrel, [101], [186], [243] Stag, [325] —— Irish, [67] Standfuss, [155] Stanley crane, [248], [279] St Hilaire, T. G., [2], [356] Stick insect, [209] Stictoptera annulosa, [104] Stoat, [119], [190], [290] Stolzmann, [327]-9, [342], [343] Stonechat, [353] Stork, [247], [282] “Strand Magazine,” [64] Strix flammea, [289] Struggle for existence, [31], [32], [48] —— for nourishment, [167] Suchetet, A., [126], [130] Sula capensis, [282] S. serrator, [282] Sunbird, [324] Surniculus lugubris, [235], [243] Survival of the fittest, [32] Survival value, [33], [34] Swallow, [250], [251], [279], [361] Swallow-shrike, [281] Swallow-tail butterfly, [179] Swan, [100] Swift, [243], [250] Swimming bladder of fishes, [36], [37] Sycalis flaveola, [244] Syrphidæ, [178]

T Tachycineta leucorrhoa, [361] Tadorna cornuta, [129] T. tadornoides, [129] Tails, [62], [64] Tait, Mr, [356] Tanager, [281] Tapir, [42] Tasmanian devil, [282] Teal, [290], [316] Teasel, fuller’s, [58] Teeth, molar, [105] Tegetmeier, Mr, [307] Tern, [62], [278] Terpsiphone paradisi, [202], [298], [304], [316], [324] Tetraogallus, [337] Tetraonidæ, [125] Tetrapteryx paradisea, [249] Tetrao tetrix, [129] T. urogallus, [129] Thamnobia cambayensis, [202], [275] T. fulicata, [202], [378] Thayer, Mr Abbot, [184]-7 Thompson, Seton, [354] Thomson, [103], [136], [145], [166], [306], [326], [340] Throat disease, [353] “Through Southern Mexico,” [197], [245] “Through the Heart of Patagonia,” [359] Thrush, [203], [207], [355] Tiger, [334] Tit, [245] Toad, [210], [219], [241] Toad-flax, [56] Tortoise, [222] Trefoil, [274] Trochilium, [229] Trogon, [62] Tropidonotus piscator, [220] Troupial, [244], [281], [284] Tsetse-fly, [352] Tupaia, [180], [216] T. ellioti, [216] Turbit, [72], [91]-3 “Turbit, The Modern,” [91] Turkey, [95], [363] Turnspit dog, [59] Turtur cambayensis, [333] T. suratensis, [333] T. risorius, [33], [123], [126] Tylor, Mr Alfred, [287]

U Ungulates, [67] Unilateral transmission, [341] Unit characters, [148]-52 Uria grylle, [245] U. lacrymans, [58] Urial, [120], [130], [131] Urodynamis tritensis, [243]

V Valezina, [103] Vanessa levana, [154] V. prorsa, [154] Vapourer moth, [215] Variation, [52]-110 —— cause of, [59]-60 —— continuous, [56], [69], [76], [105] —— definite, [55] —— determinate, [55] —— discontinuous, [43], [56], [72], [73], [76], [78], [79], [87], [105], [106], [133], [159], [295] —— germinal, [106]-10, [133] —— indefinite, [55], [59] —— somatic, [106]-110 Viola, [260] V. tricolor, [260] Volckamer, [86] Vulture, [282]

W Waggett, [12] Wagner, [369], [372] Wagtail, [122], [203] Wallace, [3], [10], [13], [14], [25], [26], [35]-42, [53], [112], [114], [116], [117], [171], [175], [177], [183], [184], [207], [213], [228], [230], [251], [253], [256], [287], [296], [308], [321]-7, [343], [372], [377] Wallaceian school of biologists, [14], [24], [25], [47], [192], [210], [251], [346], [347], [366], [377] Wallaceism, [172], [202] Walrus, [190] Warblers, British, [315], [332] Warning colours, [173], [176], [198], [212]-26 Wasp, [174], [178], [179], [214], [227] Wasp-beetle, [229] Water-rail, [251] Waxbill, blue-bellied, [104] Weasel, [190] Weaver, red-billed, [98] Weber, [86] Weir, Mr Jenner, [299] Weismann, [25], [106], [107], [151], [154] Weka rail, [365] “Westminster Review,” [112] Weston, G. E., [127] Whale, [42], [185], [190], [193] Wheatear, [253] Whinchat, [253] Wiesner, [151] Wilson, Prof. E. B., [166] Winter coat, [188] Wolf, [48], [130], [185], [192] Wonder horse, [95], [96] Woodpecker, [102] Wright, Mr, [304] Wyman, Professor, [357]

X X-element, [165]

Y Yak, [120] Yarrow, [268] “Year-book of the Smithsonian Institution,” [184] Yerbury, Col., [239] Youatt, [63]

Z Zebra, [196] Zebu, [120] Zocher & Co., [56] Zoological Gardens, Lahore, [309] ——, London, [104], [119], [126], [130], [206], [304], [316] Zoological Society of London, [330] Zygæna filipendulæ, [102]

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By DOUGLAS DEWAR