LECTUREPAGE
I.Introductory[1]
II.The Darwinian Theory[25]
III.The Darwinian Theory (continued)[42]
IV. The Coloration of Animals and its relation to the
Processes of Selection		[57]
V.True Mimicry[91]
VI.Protective Adaptations in Plants[119]
VII.Carnivorous Plants[132]
VIII.The Instincts of Animals[141]
IX.Organic Partnerships or Symbiosis[161]
X.The Origin of Flowers[179]
XI.Sexual Selection[210]
XII.Intra-Selection or Selection among Tissues[240]
XIII.Reproduction in Unicellular Organisms[253]
XIV.Reproduction by Germ-cells[266]
XV.The Process of Fertilization[286]
XVI.Fertilization in Plants and Unicellular Organisms
and its immediate significance		[312]
XVII.The Germ-plasm Theory[345]
XVIII.The Germ-plasm Theory (continued)[373]
XIX.The Germ-plasm Theory (continued)[392]

LIST OF ILLUSTRATIONS

FIGUREPAGE
1.Group of various races of domestic pigeons[35]
2.Longitudinally striped caterpillar of a Satyrid[67]
3.Full-grown caterpillar of the Eyed Hawk-moth (Smerinthus ocellatus)[67]
4.Full-grown caterpillar of the Elephant Hawk-moth (Chærocampa elpenor)[68]
5.The Eyed Hawk-moth in its 'terrifying attitude'[69]
6.Under surface of the wings of Caligo[70]
7.Caterpillar of a North American Darapsa[71]
8.Caterpillar of the Buckthorn Hawk-moth (Deilephila hippophaës)[73]
9.Hebomoja glaucippe, from India; under surface[76]
10.Xylina vetusta, in flight and at rest[77]
11.Tropidoderus childreni, in flying pose[79]
12.Notodonta camelina, in flight and at rest[80]
13.Kallima paralecta, from India, right under side of the butterfly at rest[83], [357]
14.Cœnophlebia archidona, from Bolivia, in its resting attitude[85]
15.Cærois chorinæus, from the lower Amazon, in its resting attitude[86]
16.Phyllodes ornata, from Assam[87]
17.Caterpillar of Selenia tetralunaria, seated on a birch twig[90], [360]
18.Upper surfaces of Acræa egina, Papilio ridleyanus, and Pseudacræa boisduvalii[102]
19.Barbed bristles of Opuntia rafinesquii[123]
20.Vertical section through a piece of a leaf of the Stinging-nettle (Urtica dioica)[123]
21.A piece of a twig of Barberry (Berberis vulgaris)[124]
22.Tragacanth (Astragalus tragacantha)[125]
23.Bladderwort (Utricularia grafiana)[133]
24.Pitcher of Nepenthes villosa[134]
25.Butterwort (Pinguicula vulgaris)[136]
26.The Sundew (Drosera rotundifolia)[137]
27.A leaf of the Sundew[137]
28.Leaf of Venus Fly-trap[138]
29.Aldrovandia vesiculosa[138]
30.Aldrovandia, its trap apparatus[139]
31.Sea-cucumber (Cucumaria)[148]
32.Metamorphosis of Sitaris humeralis, an oil-beetle[150]
33.Cocoon of the Emperor Moth (Saturnia carpini)[158]
34.Hermit-crab[163]
35.Hydra viridis, the Green Freshwater Polyp[169]
36.Amœba viridis[170]
37.Twig of an Imbauba-tree, showing hair cushions[172]
38.A fragment of a Lichen[173]
39.A fragment of a Silver Poplar root[176]
40.Potentilla verna[181]
41.Flower of Meadow Sage[183]
42.Alpine Lousewort (Pedicularis asplenifolia)[184]
43.Flower of Birthwort (Aristolochia clematitis)[185]
44.Alpine Butterwort (Pinguicula alpina)[185]
45.Daphne mezereum and Daphne striata[187]
46.Common Orchis (Orchis mascula)[188]
47.Head of a Butterfly[190]
48.Mouth-parts of the Cockroach[191]
49.Head of the Bee[192]
50.Flowers of the Willow[194]
51.The Yucca-moth (Pronuba yuccasella)[201]
52.The fertilization of the Yucca[202]
53.Scent-scales of diurnal Butterflies[217]
54.A portion of the upper surface of the wing of a male 'blue' (Lycæna menalcas)[218]
55.Zeuxidia wallacei, male[218]
56.Leptodora hyalina[224]
57.Moina paradoxa, male[225]
58.Moina paradoxa, female[226]
59.An Amœba: the process of division[253]
60.Stentor rœselii, trumpet-animalcule[254]
61.Holophrya multifiliis[256]
62.Pandorina morum[257]
63.Volvox aureus[270]
64.Fucus platycarpus, brown sea-wrack[272]
65.Copulation in a Daphnid (Lyncæid)[276]
66.Spermatozoa of various Daphnids[277]
67.Spermatozoa of various animals[278]
68.Diagram of a spermatozoon[279], [338]
69.Ovum of the Sea-urchin[281], [338]
70.Daphnella[283]
71.Bythotrephes longimanus[283]
72.Sida crystallina, a Daphnid[284]
73.Diagrammatic longitudinal section of a hen's egg before incubation[285]
74.Diagram of nuclear division[288]
75.Process of fertilization in Ascaris megalocephala[296]
76.Diagram of the maturation divisions of the ovum[299]
77.Diagram of the maturation divisions of the sperm-cell[301]
78.Diagram of the maturation of a parthenogenetic ovum[305]
79.The two maturation divisions of the 'drone eggs' of the Bee[307], [337]
80.Fertilization of the ovum of a Gasteropod[310]
81.Formation of polar bodies in a Lichen[313]
82.Fertilization in the Lily[314]
83.Conjugation of Noctiluca[317]
84.Conjugation and polar body formation in the Sun-animalcule[319]
85.Diagram of the conjugation of an Infusorian[321]
86.Conjugation of an Infusorian[323]
87.Diagram to illustrate the operation of amphimixis[348]
88.Sperm-mother-cells (spermatocytes) of the Salamander[350]
89.Anterior region of the larva of a Midge[364], [393]
90.The Common Shore-Crab, seen from below[367]
91.Hind leg of a Locustid[371]
92.Echinoderm-larvæ[387]
93.Development of a limb in the pupa of a Fly[395]
94.Diagram to illustrate the phylogenetic shifting back of the origins of the germ-cells in medusoids and hydroids[412]
95.Diagram to illustrate the migration of the germ-cells in Hydromedusæ[414]

COLOURED PLATES

SOME MIMETIC BUTTERFLIES AND THEIR IMMUNE MODELS

Plate Ito face page[112]
Plate II" "[114]
Plate III" "[116]