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 PACHYDERMA 44 52. The same from below 44 53. TRACHYNEMA DIGITALE 45 54. HALICLYSTUS AURICULA 46 55. Lucernaria seen from the mouth side 47 56. Young Lucernaria 48 57. Hydrarium of EUCOPE DIAPHANA 50 58. Magnified portion of Fig. 57 50 59. Part of marginal tentacles of Eucope 51 60. Young Eucope 51 61. Adult Eucope, profile 51 62. Quarter-disk of Fig. 60 51 63. Quarter-disk of Eucope older than Fig. 62 52 64. Quarter-disk of adult Eucope 52 65. OCEANIA LANGUIDA just escaped from the reproductive calycle 53 66. Same as Fig. 65 from below 53 67. Young Oceania older than Fig. 65 54 Diagram of succession of tentacles 54 68. Adult Oceania 55 69. Attitude assumed by Oceania 56 70. CLYTIA BICOPHORA escaped from reproductive calycle 57 71. Somewhat older than Fig. 70 57 72. Magnified portion of Hydrarium of Clytia 57 73. Adult Clytia 57 74. ZYGODACTYLA GROENLANDICA 58 75. The same seen in profile 59 76. TIMA FORMOSA 61 77. One of the lips of the mouth 61 78. Head of Hydrarium of Tima 62 79. MELICERTUM CAMPANULA from above (Agassiz) 63 80. The same seen in profile 64 81. Planula of Melicertum 65 82. Cluster of planulæ 65 83. Young Hydrarium 65 84. DYNAMENA PUMILA 66