LIST OF THE WOOD-CUTS. ix 



Fig. 42. Fig. 43, seen from above . • . . . . 30 



" 43. Fig. 42, seen from the broad side 30 



" 44. Pleurobrachia, immediately before the escape from the egg ..... 31 



" 45. Fig. 44, somewhat less magnified, to show the relative size of the egg-case and the 



embryo 31 



" 46. Fig. 44, seen from the actinal pole 32 



" 47. Pleurobrachia swimming freely about, seen from the broad side .... 32 



" 48. Somewhat less advanced than Fig. 47, showing the lateral tubes from the narrow 



side, as a prolongation of the ambulacral ca-\ity 33 



" 49. Pleurobrachia about in state of Fig. 47, seen from the actinal pole . . . .33 



" 50. Adult Pleurobrachia, natural size, from broad and narrow side .... 33 



" 51. Adult Pleurobrachia in a natural attitude, natural size ...... 33 



" 52. Young Idyia roseola, seen from the narrow side 36 



" 53. Fig. 52, seen from the abactinal pole ......... 36 



" 54. Young Idyia, with distinct ambulacral tubes, seen from the narrow side . . 36 



" 55. Fig. 54, seen from the abactinal pole 37 



" 56. Somewhat more advanced than Fig. 54, seen from the broad side ... 37 



" 57. The long chymiferous tubes extend to the level of the actinostome . . . .37 



" 58. The long chymiferous tubes have united with the lateral tubes ; first trace of the 



ramifications of the long tubes . . . . . . . . .37 



" 59. The short ambulacra have nearly united with the circular tube .... 37 



" 60. The circuit is now complete between the short and long ambulacra ; the spurs or 



ramifications of the chymiferous tubes are numerous, resembling somewhat 



those of the adult ........... 37 



" 61. Fig. 57, seen from the abactinal pole 38 



" 62. Adult Idyia, reduced in size one half. (L. Agassiz.) 38 



" 63. Idyopsis Clarkii, seen from the broad side. (L. Agassiz.) 39 



" 64. Fig. 63, seen from the abactinal pole. (L. Agassiz.) ...... 39 



" 65. Profile view of Aurelia flavidula, much reduced. (L. Agassiz.) . . .42 



" 66. Abactinal view of Aurelia flavidula. (L. Agassiz.) 42 



" 67. Cyanea arctic a, very much reduced. (L. Agassiz.) 45 



" 68. Pelagia cyanella. (L. Agassiz.) 47 



" 69. Dactylometra quixqdecirra, reduced about one fourth 48 



" 70. Profile view of Campaxella pachyderma 53 



" 71. Actinal view of Fig. 70 53 



" 72. A somewhat more magnified view of Fig. 71 ....... 53 



" 73. View of part of the actinal surface 53 



" 74. Magnified profile view of portion of the base of a tentacle ..... 53 



" 75. View of basal portion of tentacle, seen from above 53 



" 76. Profile view of Trachynema camtscuaticum 56 



" 77. One of the genital organs .56 



" 78. Section of Trachynema ........... 56 



" 79. Chymiferous cavity at the end of the gelatinous proboscis . . . . .56 



" 80. View of Trachj'nema from above .......... 56 



" 81. Adult female Trachyxema digitale, seen in profile 57 



" 82. Actinal view of the veil and circular tube of a very young Trachynema . . 57 



" 83. Profile view of a part of the circular tube 57 



" 84. Profile view of a young Trachynema, about one eighth of an inch in height . 58 



" 85. Somewhat more advanced than Fig. 84 58 



" 86. Young Trachynema, measuring over one third of an inch in height ... 69 



" 87. ? LiRioPE scuTiGERA. (L. Agassiz.) 60 



" 88. Hahclystus auricula, seen from the actinal pole 63 



" 89. Difierent attitudes of Haliclystus auricula, attached to eel-grass . . . .63 



" 90. Young Haliclystus auricula, magnified ......... 63 



" 91. TiAROPSis DIADEMATA, natural size. (L. Agassiz.) 69 



" 92. Young Tiaropsis, having twenty-four tentacles ....... 69 



" 93. Young Tiaropsis, having forty tentacles. (L. Agassiz.) ...... 69 



" 94. Two marginal tentacles of OcEAXiA LANGUID A, with a portion of the circular tube 70 



" 95. Magnified view of the actinostome 71 



