X LIST OF THE WOOD-CUTS. 



Fig. 96. Young Medusa of Oceania laxguida, immediately after escaping from the re- 

 productive calycle 72 



" 97. The same, seen from the actinal pole 72 



" 98. Somewhat more advanced ^Medusa 72 



" 99. Quarter of the disk of a still more advanced Oceania 72 



" 100. Adult Oceania languida, natural size 73 



" 101. Magnified view of an ovary 73 



" 102. Peculiar attitude sometimes assumed by the Medusae 73 



" 103. One of the four lips of the actinostome of OCKANIA GREGARIA ... 74 



" 104. EUCHEILOTA VENTRICULARIS 74 



" 105. More magnified view of a quarter of the disk ....... 75 



" 106. EdCHEILOTA DDODECniALIS 75 



" 107. Junction of one of the chymiferous tubes with the circular tube ... 76 



" 107". Female Medusa of Eucheilota duodecimalis 76 



" 108. Clytia BicoPHORA, immediately after its escape from the reproductive calycle 78 



" 109. A somewhat older Medusa . 78 



" 110. An adult Medusa, measuring a quarter of an inch 78 



" 111. Sterile Hydra and reproductive calycle, seen from the broad side .... 79 



" 112. Reproductive calycle of Platypyxis CYLiNDRic A, seen from the broad side . 80 



" 113. The same, seen from the narrow side ......... 80 



" 114. Sterile Hydra of Platypyxis cylindrica. (L. Agassiz.) 80 



" 115. A EucopE DiAPHANA, Seen in profile, just after its escape from the reproductive 



calycle 83 



" 116. Quarter of the disk of the same, seen from above . 83 



" 117. A more advanced Eucope, with the second set of tentacles .... 83 



" 118. An adult Eucope, seen in profile 84 



" 119. Quarter of Fig. 118, more magnified 84 



" 1 20. Magnified view of the circular tube of a young Eucope 84 



" 121. Spermaries of Eucope ........... 84 



" 122. Female genital organs ............ 84 



" 123. Proboscis of an adult Medusa 85 



" 124. Hydrarium of Eucope diaphana, natural size 85 



" 125. Magnified view of a sterile Hydra and reproductive calycle .... 85 



" 126. Magnified view of part of main stem of Eucope POLYGENA 87 



" 127. Eucope PYRiFORJiis, seen in profile 88 



" 128. Quarter-disk of same Medusa 88 



" 129. Portion of a Hydrarium of Fig. 127 88 



" 130. Quarter-disk of Eucope articulata 89 



" 131. Portion of a Hydrarium of Eucope articulata ....... 89 



" 132. Hydrarium of Eucope eusiformis 90 



" 133. Quarter-disk of the Medusa of Fig. 132 90 



" 134. Portion of stem of Hydrarium of Obelia commissuralis 91 



" 135. Quarter-disk of the Medusa of Fig. 134 92 



" 136. Profile view, natural size, of Rhegmatodes tenuis 95 



" 137. Quarter-disk of Fig. 136, seen from the actinal side 96 



" 138. Magnified portion of the circular canal ......... 96 



" 139. Rhegmatodes FLORIDANUS, natural size. (L. Agassiz.) .... 97 



" 140. Actinostome of Stomobrachium tentaculatum, magnified .... 98 



" 141. Stomobrachium tentaculatum, seen from the abactinal pole, natural size . . 98 



" 142. Same as Fig. 141, seen in profile 99 



" 143. Portion of the disk of Halopsis ocellata, seen from the abactinal pole, some- 

 what reduced 100 



" 144. Cavity from which the chjTniferous tubes radiate 100 



" 145. Profile, natural size, of Halopsis ocellata 100 



" 146. Magnified part of circular tube 101 



" 147. Magnified view of one of the eyes .......... 101 



" 148. Young Halopsis ocellata, natural size 101 



" 149. Young Halopsis ocellata, one fifth of an inch in height . . . . . .101 



" 150. Magnified portion of circular tube of Fig. 149 ....... 101 



