x LIST OF THE WOOD-CUTS. 



Fig. 96. Young Medusa of OCEANIA LANGUIDA, 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 Medusas ...... 73 



" 103. One of the four lips of the actinostonie of OCEANIA GREG ARIA ... 74 



" 104. EUCHEILOTA VENTRICULARIS 74 



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



" 106. EUCHEILOTA DUODECIMALS 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 CYLINDRICA, 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 



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



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



" 127. EUCOPE PYRIFORMIS, 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 FUSIFORMIS 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 



" 1 38. Magnified portion of the circular canal ......... 96 



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



" 140. Actinostonie 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 chymiferous 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 



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