CONTENTS.

Page
[On Radiates in General]1
[General Sketch of the Polyps]5
[Actinoids]7
[Madreporians]16
[Halcyonoids]19
[General Sketch of Acalephs]21
[Ctenophoræ]26
[Embryology of Ctenophoræ]34
[Discophoræ]37
[Hydroids]49
[Mode of Catching Jelly-Fishes] 85
[Echinoderms]91
[Holothurians]95
[Echinoids] 101
[Star-Fishes]108
[Ophiurans] 115
[Crinoids] 120
[Embryology of Echinoderms]123
[Distribution of Life in the Ocean]141
[Systematic Table] 152
[Index]154

LIST OF THE WOOD-CUTS.

Unless otherwise specified, the illustrations are drawn from nature by Alex. Agassiz.

Fig. Page
[1.]Transverse section of an Actinia (Agassiz)5
[2, 3, 4.]Actinia in different degrees of expansion (Agassiz)8
[5.]Metridium marginatum fully expanded8
[6.]Vertical section of an Actinia10
[7.]View from above of an expanded Actinia11
[8, 9.]Young Actiniæ11
[10.]Rhodactinia Davisii13
[11.]Arachnactis brachiolata14
[12.]Young Arachnactis14
[13.]Young Arachnactis showing the mouth14
[14.]Bicidium parasiticum15
[15.]Halcampa albida16
[16.]Colony of Astrangia Danæ17
[17.]Magnified individuals of Astrangia17
[18.]Single individual of Astrangia18
[19.]Lasso-cell of Astrangia18
[20.]Limestone pit of Astrangia19
[21.]Single individual of Halcyonium carneum19
[22.]Halcyonium community20
[23.]Expanded individual of Halcyonium20
[24.]Branch of Millepora alcicornis (Agassiz)22
[25.]Expanded animals of Millepora (Agassiz)22
[26.]Transverse section of branch of Millepora (Agassiz)23
[27.]Pleurobrachia rhododactyla (Agassiz)27
[28.]The same as Fig. 27 seen in plane of tentacles (Agassiz)28
[29.]Pleurobrachia in motion29
[30.]Pleurobrachia seen from the extremity opposite the mouth30
[31.]Bolina alata seen from the broad side (Agassiz)31
[32.]Bolina seen from the narrow side (Agassiz)31
[33.]Idyia roseola seen from the broad side (Agassiz)32
[34.]Young Pleurobrachia still in the egg35
[35.]Young Pleurobrachia swimming in the egg35
[36.] Young Pleurobrachia resembling already adult35
[37.]Young Idyia35
[38.] Young Idyia seen from the anal pole36
[39.] Idyia somewhat older than Fig. 3736
[40.] Idyia still older36
[41.] Young Bolina in stage resembling Pleurobrachia37
[42.] Young Bolina seen from the broad side37
[43.] Young Bolina seen from the narrow side37
[44.] Cyanea Arctica40
[45.] Scyphistoma of Aurelia (Agassiz)41
[46.] Scyphistoma older than Fig. 45 (Agassiz)41
[47.] Strobila of Aurelia (Agassiz)41
[48.] Ephyra of Aurelia (Agassiz)42
[49.] Aurelia flavidula seen in profile (Agassiz)42
[50.] Aurelia seen from above (Agassiz)43
[51.]Campanella pachyderma44
[52.]The same from below44
[53.]Trachynema digitale45
[54.]Haliclystus auricula46
[55.]Lucernaria seen from the mouth side47
[56.]Young Lucernaria48
[57.]Hydrarium of Eucope diaphana50
[58.]Magnified portion of Fig. 5750
[59.]Part of marginal tentacles of Eucope51
[60.]Young Eucope51
[61.]Adult Eucope, profile51
[62.]Quarter-disk of Fig. 6051
[63.]Quarter-disk of Eucope older than Fig. 6252
[64.]Quarter-disk of adult Eucope52
[65.]Oceania languida just escaped from the reproductive calycle53
[66.]Same as Fig. 65 from below53
[67.]Young Oceania older than Fig. 6554
[Diagram of succession of tentacles]55
[68.]Adult Oceania55
[69.]Attitude assumed by Oceania56
[70.]Clytia bicophora escaped from reproductive calycle57
[71.]Somewhat older than Fig. 7057
[72.]Magnified portion of Hydrarium of Clytia57
[73.]Adult Clytia57
[74.]Zygodactyla groenlandica58
[75.]The same seen in profile59
[76.]Tima formosa61
[77.]One of the lips of the mouth61
[78.]Head of Hydrarium of Tima62
[79.]Melicertum campanula from above (Agassiz)63
[80.]The same seen in profile64
[81.]Planula of Melicertum65
[82.]Cluster of planulæ65
[83.]Young Hydrarium65
[84.]Dynamena pumila66
[85.]Magnified portion of Fig. 8466
[86.]Dyphasia rosacea67
[87.]Medusa of Lafoea67
[88.]Colony of Coryne mirabilis (Agassiz)68
[89.]Magnified head of Fig. 88 (Agassiz)68
[90.]Free Medusa of Coryne (Agassiz)68
[91.]Turris vesicaria69
[92.]Bougainvillia superciliaris70
[93.]Hydrarium of Bougainvillia70
[94, 95, 96.]Medusæ buds of Fig. 9371
[97.]Young Medusa just freed from the Hydroid71
[98.]Tubularia couthouyi (Agassiz)72
[99.]Cluster of Medusæ of Fig. 98 (Agassiz)72
[100.]Female colony of Hydractinia polyclina (Agassiz)73
[101.]Male colony of the same (Agassiz)73
[102.]Unsymmetrical Medusa of Hybocodon prolifer (Agassiz)74
[103.]Medusa bud of Hybocodon (Agassiz)74
[104.]Hybocodon Hydrarium (Agassiz)74
[105.]Dysmorphosa fulgurans75
[106.]Proboscis of Fig. 105 with young Medusæ75
[107.]Young Nanomia cara76
[108.]Nanomia with rudimentary Medusæ76
[109.]Nanomia somewhat older than Fig. 10877
[110.]Heart-shaped swimming bell of Nanomia77
[111.]Cluster of Medusæ with tentacles having pendent knobs78
[112.]Magnified pendent knob79
[113.]Medusa with corkscrew-shaped tentacles79
[114.]Medusa with simple tentacle80
[115.]Adult Nanomia81
[116.]Oil float of Nanomia82
[117.]Physalia arethusa (Agassiz)83
[118.]Bunch of Hydræ (Agassiz)84
[119.]Cluster of Medusæ (Agassiz)84
[120.]Velella mutica (Agassiz)84
[121.]Free Medusa of Velella (Agassiz)84
[122.]Ptychogena lactea86
[123.]Ovary of Ptychogena87
[124.]Synapta tenuis95
[125.]Anchor of Synapta96
[126.]Caudina arenata97
[127.]Cuvieria squamata98
[128.]Young Cuvieria99
[129.]Cuvieria somewhat older than Fig. 12899
[130.]Pentacta frondosa100
[131.]Toxopneustes drobachiensis102
[132.]Portion of shell of Fig. 131 without spines (Agassiz)103
[133.]Sea-urchin shell without spines (Agassiz)103
[134.]Sea-urchin from the mouth side (Agassiz)104
[135.]Magnified spine104
[136.]Transverse section of spine105
[137.]Pedicellaria of Sea-urchin105
[138.]Teeth of Sea-urchin106
[139.]Echinarachnius parma107
[140.]Transverse section of Echinarachnius (Agassiz)108
[141.]Ray of Star-fish, seen from mouth side (Agassiz)109
[142.]Astracanthion berylinus110
[143.]Single spine of Star-fish111
[144.]Limestone network of back of Star-fish111
[145.]Madreporic body of Star-fish111
[146.]Cribrella oculata112
[147.]Ctenodiscus crispatus114
[148.]Ophiopholis bellis115
[149.]Arm of Fig. 148, from the mouth side (Agassiz)116
[150.]Tentacle of Ophiopholis116
[151.]Astrophyton agassizii118
[152.]Pentacrinus121
[153.]Alecto meridionalis122
[154.]Young Comatulæ122
[Figs 155, 156, 157.]Egg of Star-fish in different stages of development124
[158.]Larva just hatched from egg125
[159-164.]Successive stages of development of Larva125
[165.]Larva in which arms are developing126
[166.]Adult Star-fish Larva (Brachiolaria)127
[167.]Fig. 166 seen in profile128
[168-170.]Young Star-fish (Astracanthion) in different stages of development129
[171.]Lower side of ray of young Star-fish130
[172.]Very young Star-fish seen in profile130, 130
[173-175.]Larvæ of Sea-urchin (Toxopneustes) in different stages of development130, 131
[176.]Adult Larva of Sea-urchin132
[177.]Fig. 176 seen endways133
[178.]Sea-urchin resorbing the arms of the larva133
[179-181.]Successive stages of young Sea-urchin133, 134
[182.]Ophiuran which has nearly resorbed the larva135
[183.]Larva of Ophiuran (Pluteus)136
[184.]Young Ophiuran137
[185.]Cluster of eggs of Star-fishes over mouth of parent137
[Diagram of a rocky beach]149