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Full text of "North American Acalephæ"

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ILLUSTRATED CATALOGUE 




OF THE 



MUSEUM OF COMPARATIYE ZOOLOGY, 



AT HARVARD COLLEGE. 



Published by order of the Legislature of Massachusetts. 



No. II. 

NORTH AMERICAN ACALEPH^l. 



BT 



ALEXANDER AGASSIZ. 



CAMBRIDGE: 
FOR SALE BY SEVER AND FRANCIS. 

1865. 



ILLUSTRATED CATALOGUE 



OF THE 



MUSEUM OF COMPARATIVE ZOOLOGY, 



AT HARVARD COLLEGE. 



Published by order of the Legislature of Massachusetts. 



No. II. 
NORTH AMERICAN ACALEPH^l. 



BY 



ALEXANDER AGASSIZ. 



CAMBRIDGE: 
FOR SALE BY SEVER AND FRANCIS. 

1865. 



UNIVERSITY PRESS : WELCH, BICELOW, & Co., 
CAMBRIDGE. 



THE publication of the Illustrated Catalogue of the Museum of 
Comparative Zoology has been undertaken with a threefold 
object. In the first place, like the catalogues of most institutions of 
a similar character, it is intended to make the contents of our Museum 
generally known, and to facilitate our exchanges. In the second place, 
to be the medium of publication of the novelties received at the 
Museum, which require to be described and illustrated by diagrams 
or wood-cuts, or more elaborate plates. Finally, it is hoped that it 
may be the basis of a systematic revision of such natural groups of 
the animal kingdom as are most fully represented in our collections, 
and that it may, as far as possible, present to the scientific world 
the results of the investigations carried on in the Museum with a 
view of ascertaining the natural limits of the Faunae at the present 
time and in past ages, and the genetic relations which may exist 
between the order of succession of organized beings upon the earth, 
their mode of growth, and their metamorphoses during their embry- 
onic life, and the plan and complication of their structure in their 
adult condition. 

The means for publishing this work have been most liberally granted 
by the Legislature, at a time when, in a less enlightened assembly, 
the material cares of the community would have engaged their 
exclusive attention. 

L. AGASSIZ. 
CAMBRIDGE, March 28, 1865. 



PREFACE. 



HHHE progress of our knowledge of the Class of Acalephs is at 
present so closely linked with every new observation which may 
be brought up in the history of the development of these animals, 
that it has been thought advisable to extend this Catalogue some- 
what, and not make it simply an enumeration of the Acalephs in the 
collection of the Museum of Comparative Zoology at Cambridge. It 
has, however, been limited to the North American species ; and even 
many of the Sertularians, Campanularians, and Tubularians in the col- 
lection are not described or mentioned here, because our information 
with regard to them is too scanty to be available. The mere enu- 
meration, with short descriptions, of Hydroids, the development of 
which has not been fully traced, would probably only add, in the 
course of a few years, synonymes to some of the Medusce, the adult 
stages of which may be well known, and would not advance in the 
least degree our acquaintance with the North American Acalephs. 
To make this Catalogue useful to American students, a few species 
described by other authors, of which there are no specimens in the 
Museum collection, are added, to facilitate further investigations. This 
is done with the less hesitation, as it is hoped that in a short time 
most of the species thus enumerated will have been figured in the 
diagrams of the Museum. 

In the descriptions of the species, constant reference has been made 
to the bearing of the facts discussed, on the classification of Acalephs, 
and consequently much has been introduced which would be out of 
place in a descriptive catalogue. The wood-cuts, with the exception 
of a few borrowed from the Contributions to the Natural History of 
the United States by Professor Agassiz, have all been drawn on wood 
from nature by myself, and, though not highly finished, will yet 
generally give a better idea of the Acalephs, in this simple outline, 
than could have been done by a more finished wood-cut. Such an 
elaborate catalogue of Acalephs may seem somewhat out of place 



vi PREFACE. 

here, but as special attention has been paid to them in the Museum 
at Cambridge, and as Professor Agassiz has introduced there a large 
number of diagrams, all copied from original drawings, to illustrate 
the structure and colors of animals which were too small or too 
perishable to be preserved in the ordinary way, these valuable mate- 
rials have been extensively used in the preparation of this Catalogue, 
as forming actually a part of the collections exhibited in the show- 
cases. The diagrams, as well as the authorities from which they are 
taken, are carefully enumerated below, after the specimens preserved 
in the collection. 

For the facilities I have enjoyed in collecting the materials for this 
Catalogue I am mainly indebted to Mr. and Mrs. J. M. Forbes, to Pro- 
fessor A. D. Bache, Superintendent of the Coast Survey, to Mr. T. G. 
Gary, and to Professor Agassiz. I have also to thank, for specimens and 
valuable information, Professor Joseph Leidy, Dr. Fritz Miiller of De- 
sterro, Dr. W. Stimpson, and Professor H. J. Clark, who had already 
arranged the greater part of the Hydroids before the collection of Aca- 
lephs was placed in my charge. The Museum is also indebted for 
specimens to many other persons, whose names will be referred to in 

connection with the different species. 

A. AGASSIZ. 

CAMBRIDGE, MASS., February, 1865. 



CONTENTS. 



PAGE 

LIST OF THE WOOD-CUTS ........... viii 

BIBLIOGRAPHY 3 

CTENOPHOR^E 7 

DISCOPHOR^E ............. 40 

HYDROID^E .............. 64 

GEOGRAPHICAL DISTRIBUTION. 221 

SYSTEMATIC TABLE OF THE ORDERS AND FAMILIES 227 

INDEX OF GENERA AND SPECIES . . . 229 



NO. II. 



LIST OF THE WOOD-CUTS. 



[NOTE. Unless otherwise credited, the Figures are drawn from nature by Alex. Agassiz.] 



PAGE 

Fig. 1. Young BOLIXA ALATA, seen from the narrow side ... ... 15 

" 2. BoEna in state of Fig. 1, seen from the broad side . . . . . . 16 

" 3. Somewhat younger than Fig. 1, seen from the abactinal pole . . . . .16 

" 4. Young Bolina, seen from the abactinal pole, older than previous figures . . 16 

" 5. Formation of lateral tubes in young- Bolina 16 

/ O 

" 6. Bolina in which lobes begin to appear, seen from the narrow side, same state as Fig. 4 16 

" 7. Somewhat more advanced than Fig. 6, seen from the actinal side . . . .16 

" 8. The tentacular ambulacra have united, and the lobes project well beyond the open- 
ing of the mouth . ........... 1 7 

" 9. About in the condition of Fig. 1, seen from the broad side . . . . . 17 

" 10. Somewhat younger than Fig. 8, seen from the broad side . .... 17 

" 11. Fig. 8, seen from the broad side .......... 17 

" 12. Bolina showing first appearance of the auricles, seen from the broad side . . .17 

" 1 3. Bolina in stage of Fig. 1 2, seen from the narrow side ...... 17 

" 14. Fig. 13, seen from the actinal pole ..... .... 18 

" 15. Adult Bolina, seen from the broad side. (L. Agassiz.) . . ... 18 

" 16. Fig. 15, seen from the narrow side. (L. Agassiz.) ....... 18 

" 17. Bolina, seen from the actinal pole. (L. Agassiz.) . 18 

" 18. Bolina, seen from the abactinal pole. (L. Agassiz.) ... ... 18 

" 19. BOLIXA VITREA, seen from the broad side. (L. Agassiz.) 19 

" 20. MXEMIOPSIS GARDEN:, seen from the broad side. (L. Agassiz.) . . . .20 

" 21. Fig. 20, seen from the actinal pole. (L. Agassiz.) 20 

" 22. MXEMIOPSIS LEIDYI, seen from the broad side . .... 21 

" 23. Same as Fig. 22, seen from the narrow side ........ 21 

" 24. A part of the tentacular apparatus near the opening of the actinostome . . .22 

" 25. LESUEURIA IIYBOPTERA, seen from the broad side . . . .24 

" 26. Fig. 25, seen from the narrow side .......... 24 

" 27. The same, seen from the abactinal pole ......... 25 

" 28. Seen from the actinal pole 25 

" 29. Adult MERTEXSIA OVUM, seen from the broad side . . ... 27 

" 30. Young Mertensia, seen from the broad side . ...... 27 

" 31. Fig. 30, seen from the abactinal pole ...... . 27 

" 32. Somewhat more advanced Mertensia, seen from the narrow side . . .28 

" 33. Same as Fig. 32, seen from the actinal pole . ... 28 

" 34. Still more advanced Mertensia, seen from the narrow side ...... 28 

" 35. Fig. 34, seen from the actinal pole .... .... 28 

" 36. Still further advanced Mertensia, seen from the broad side ..... 29 

" 37. Young Mertensia, about in the same condition as that of the preceding figure, seen 

from the narrow side ........... 29 

" 38. Young PLEUROBRACHIA RHOPODACTYLA, seen from the broad side . 30 

" 39. Same as Fig. 38, seen from the narrow side 30 

" 40. Same as Fig. 38, seen from below ... 30 

" 41. Somewhat more advanced, seen from the broad side .... . . 30 



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. F!g. 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 ambulacra! cavity . . 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 navidula. (L. Agassiz.) ...... 42 

" 67. CYAXEA ARCTIC A, very much reduced. (L. Agassiz.) . . 45 

" 68. PELAGIA CYAXELLA. (L. Agassiz.) 47 

" 69. DACTYLOMETRA QUIXQUECIRRA, 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 TRACIIYXEMA CAMTSCHATICUM 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 Trachynema from above . ..... .56 

" 81. Adult female TRACIIYXEMA DIGIT ALE, 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 

u 86. Young Trachynema, measuring over one third of an inch in height . 59 

87. ? LIRIOPE SCUTIGERA. (L. Agassiz.) 60 

88. HALICLYSTUS AURICULA, seen from the actinal pole .... 63 
" 89. Different 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 LAXGUIDA, with a portion of the circular tube 70 

95. Magnified view of the actinostome ..... .71 



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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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LIST OF THE WOOD-CUTS. xi 

151. Profile view, somewhat magnified, of HALOPSIS CRUCIATA 102 

" 152. Natural attitude of the same Medusa (Fig. 151) 102 

" 153. Abactinal view of ZYGODACTYLA GROEXLANDICA 104 

' 154. Profile view of Fig. 153, half natural size 104 

" 155. Portion of the circular tube . . . . . . . . . . .104 

" 156. Young Zygodactyla, greatly magnified ........ 105 

" 157. Profile view of ZYGODACTYLA CRASSA, somewhat reduced in size . . .106 

" 158. Quarter-disk of Zygodactyla crassa . . . . . . . . . 107 

" 159. Portion of the disk of ZYGODACTYLA CYAXEA, from the abactinal pole. (L. Ag.) 107 

" 159". CREMATOSTOMA FLAVA, in profile 109 

" 160. Portion of the disk of ^EQUOREA ALBIDA, from the abactinal pole . . . 110 

" 161. A natural attitude of zEquorea albida 110 

" 162. Magnified view of the marginal tube ........ Ill 

" 163. EIRENE CCERULEA. (L. Agassiz.) 112 

" 164. TIMA FORMOSA, half natural size 113 

" 165. Quarter of the disk, from the abactinal pole, natural size . . . . .113 

" 166. Digestive cavity and actinostome ......... 113 

" 167. Portion of the ovary . . . . . . . . . . . .114 

" 168. Magnified portion of the circular tube ........ 114 

" 169. Young Tima formosa, natural size . . . . . . . . . .114 

" 170. Digestive cavity of Fig. 169 114 

" 171. Young Planula; of Tima ........... 115 

" 172. Single Hydra of the tuft of a Tima Hydrarium, greatly magnified . . . 115 

" 173. Profile of EUTIMA LIMPIDA, reduced in size 116 

" 174. Quarter-disk of Fig. 1 73 . 116 

" 175. Magnified view of proboscis and genital organs . . . . . . .117 

" 176. Magnified portion of a part of the circular canal . . . . . . 117 

" 177. Magnified marginal capsule . . . . . . . . . . .117 

" 178. Magnified view of the rudimentary tentacles 117 

" 179. Profile view, somewhat magnified, of POLYORCHIS PENICILLATA . . .119 

" 180. Ovaries of one of the chymiferous tubes 119 

" 181. Section of bell ............. 120 

" 182. Part of disk of Fig. 1 79, seen from the abactinal pole . . . . 120 

" 183. Two of the marginal tentacles in a contracted state 120 

" 184. Adult Medusa of LAFCEA CALCARATA 122 

" 185. One of the ovaries and the actinostome . . . . . . . .123 

" 186. Actinostome, actinal view .......... 123 

187. Magnified view of a portion of the circular tube ... ... 123 

" 188. Actinostome and rudimentary ovaries, seen in profile . . . . . 123 

" 189. Different attitude of Medusa of Fig. 184 124 

" 1 90. Hydrarium of Lafoea calcarata .......... 1 24 

" 191. Reproductive calvcle . . . . . . . . . . . .125 

" 192. Medusa immediately after its escape from the reproductive calycle . . . 125 

" 193. Medusa somewhat more advanced, from the abactinal pole . . . . .125 

' 194. Young Medusa still further advanced than Fig. 193 126 

" 195. LAODICEA CELLULARIA 127 

" 196. One of the lips of the actinostome ......... 127 

" 197. GOXIONEMUS VERTENS, attached by its tentacles 129 

" 198. The same in motion, natural size 129 

" 199. Base of a contracted tentacle . 130 

" 200. A portion of the genital organs ......... 130 

" 201. One of the chymiferous tubes and half the digestive cavity . . . 130 

" 202. Profile of MELICERTUM CAMPANULA, natural size .... 131 

" 203. Profile view of a very young Melicertum campanula ...... 132 

" 204. Half the disk of the same, seen from the actinal pole ... 132 

" 205. Young Melicertum, having only four completely formed chymiferous tubes . .132 

" 20fi. Same, seen from the abactinal pole .133 

" 207. Magnified view of the two chymiferous tubes and genital glands . . . .133 

" 208. Mode of carrying the lips of actinostome ..... . 133 



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xii LIST OF THE WOOD-CUTS. 

Fig. 209. Magnified view of marginal tentacles 133 

" 210. Spherical embryo . 134 

" 211. The same, somewhat more advanced ......... 134 

" 212. The same before it becomes attached ........ 134 

" 213. Group of embryos attached, in different stages of development . . . .134 

" 214. Different stages of growth beyond those of Fig. 213 134 

" 215. Profile of MKLICERTUM GEORGICUM, natural size 135 

" 21(5. Digestive cavity and point of junction of the chymiferous tubes . . . 135 

" 215 a . STAUROPHORA LACLNIATA, having eight tentacles 136 

" 216*. Quarter of the disk of a young Staurophora, with sixteen large tentacles . 136 

" 217. Young Medusa somewhat more advanced than Fig. 21 6 a ..... 136 

218. Different stages of actinostome intermediate between that of Figs. 215* and 219 136 

219. Young Staurophora, having the aspect of the adult 137 

220. Profile view of PTYCHOGENA LACTEA, somewhat reduced .... 138 
" 221. Magnified view of the genital organs, seen from the abactinal pole . . .138 

" 222. Same as Fig. 221, seen in profile 138 

" 223. Actinostome 138 

" 224. Magnified base of tentacles and club-shaped appendages 138 

" 225. Cluster of DYXAMEXA PUMILA. (L. Agassiz.) 141 

" 226. Magnified portion of stem of Fig. 225. (L. Agassiz.) 141 

" 227. Young NEMOPSIS BACIIEI, with four tentacles 149 

" 228. Somewhat more advanced Nemopsis . ........ 150 

" 229. Magnified view of the sensitive bulb 150 

" 230. Nemopsis in which the genital organs extend a considerable distance along the 

chymiferous tubes 150 

" 231. Magnified view of the genital organs, the actinostome, and the oral tentacles . 151 

" 232. Magnified profile view of adult BOUGAIXVILLIA SUPERCILIARIS . . . .153 

" 233. Hydromedusarium of Bougainvillia ......... 154 

" 234. Young elongated Medusa 154 

" 235. Somewhat more advanced than Fig. 234 154 

" 236. Appearance a short time before separating from the stem . . . . .154 

" 237. Same as Fig. 236, expanded 154 

" 238. Young Bougainvillia, immediately after its liberation from the Hydromedusarium 154 

" 239. Magnified view of sensitive bulb 155 

" 240. Tentacular bulb, with young tentacles . . . . . . . . .155 

" 241. Adult MARGELIS CAROLINENSIS, seen in profile, magnified .... 156 

" 242. Digestive cavity, genital pouches, oral tentacles, and actinostome . . . .156 

" 243. Sensitive bull) at base of one of the chymiferous tubes 156 

" 244. Young Margelis, having only two marginal tentacles at the base of each chymif- 
erous tube . . . . . . . . . . . . 157 

" 245. Young Margelis, seen from the abactinal pole, in condition of Fig. 244 . . . 157 

" 246. Proboscis of a Margelis, having already six tentacles at each sensitive bulb . 158 

" 247. Hydrarium, greatly reduced in size . . . . . . . . .158 

" 248. Magnified heads and Medusae buds of Margelis cai'olinensis . . . . 158 

" 249. Female MedusEe buds of EUDEXDRIUM DISPAR, in different stages of development 159 

" 250. Part of a male colony of EUDENDRIUM TENUE, magnified .... ICO 

" 251. Adult male of LIZZIA GRATA, seen in profile, magnified 161 

" 252. Quarter-disk of a young Lizzia ...... 161 

" 253. Magnified view of sensitive bulb . . . . . . . .161 

" 254. Proboscis of male Lizzia, magnified ......... 162 

" 255. One of the four lobes of the actinostome, seen from above . . . .162 

" 256. Actinal view of proboscis of young Lizzia ....... 162 

" 257. Actinal view of proboscis of an older specimen . . . . . .162 

" 258. Abactinal view of Fig. 257, somewhat less magnified ..... 162 

" 259. Adult DYSMORPHOSA FULGURANS, magnified . . . . .163 

" 260. Magnified proboscis, showing young Medusa? of the second and third generations 163 

" 261. TURRIS VESICARIA, natural size, seen in profile .... . 165 

" 2G2. The same, with the bell contracted I 65 

" 263. A portion of the disk, seen from the abactinal pole ... . . 165 



LIST OF THE WOOD-CUTS. xiii 

Fig. 264. Magnified profile view of genital organs and actinostome 165 

" 265. Magnified view of a part of a chymiferous tube . . . ." . 166 

" 266. Base of one of the chymiferous tubes, and part of the circular tube . . .166 

" 267. One of the tentacles, in a profile view 166 

" 268. One of the tentacles, seen from the abactinal pole . . . . . .166 

" 269. Young TURRITOPSIS NUTRICULA, with four marginal tentacles . . . 167 

" 270. Somewhat more advanced, having sixteen tentacles ....*.. 167 

" 271. STOMOTOCA ATRA, somewhat magnified, seen in profile ..... 169 

" 272. Magnified view of genital organs . . . . . . . . . .169 

" 273. Stomotoca atra . ............ 169 

" 274. CLAVA LEPTOSTYLA. (L. Agassiz.) 170 

" 274 a . Young WILLIA ORNATA, having only the second set of tentacles developed . 171 

" 275. Young Willia, nearly in the stage of Fig. 276, seen from the abactinal pole . .171 

" 276. Profile view of a young Willia . ......... 172 

" 277. Part of the circular tube . . . . . . . . . . .172 

" 278. View of ovary of Fig. 276 172 

" 279. Same as Fig. 278, seen from the abactinal pole . . . . . . .172 

" 280. PROBOSCIDACTYLA FLAVICIRRATA 173 

" 281. Actinostome and digestive cavity . . . . . . . . . .173 

" 282. Portion of disk to show mode of branching of chymiferous tubes, and tubes con- 
taining lasso-cells, as in Willia . . . . . . . . 1 74 

" 283. Adult CORYNE MIRABILIS, seen in profile. (L. Agassiz.) . . . . 175 

" 284. Coiyne, with proboscis contracted. (L. Agassiz.) . . . . . .175 

" 285. Coryne, with expanded proboscis. (L. Agassiz.) . . . . . . 175 

" 286. Cluster of Hydraria of Coryne mirabilis. (L. Agassiz.) 176 

" 287. Young Hydrarium of Coryne. (L. Agassiz.) ....... 176 

" 288. Magnified view of head, with Meduste buds attached. (L. Agassiz.) . . .176 

" 289. CORYNE ROSARIA, natural size 177 

" 290. Hydromedusarium of SYXDICTYON RETICULATUM, greatly magnified . . .178 

" 291. Syndictyon reticulatum, immediately after it has become freed from the Hydro- 

medusarium, in profile . . . . . . . . . .178 

" 292. One of the tentacles of Fig. 291, magnified 178 

" 293. Sensitive bulb of Fig. 291 178 

" 294. Digestive cavity of Fig. 291 .178 

" 295. Fig. 291, from actinal pole 178 

" 296. Fig. 291, from abactinal pole . 179 

" 297. Part of net-work of lasso-cells of surface of spherosome . . . . .179 

" 298. Adult Medusa in a natural attitude 180 

" 299. Same Medusa (Fig. 298) with the tentacles contracted 180 

" 300. Actinostome of adult Medusa 180 

" 301. Young DIPURENA CONICA . . . . . . . . . . .181 

" 302. Digestive cavity of a young Dipurena conica . . . . . . . 181 

" 303. Tentacle of Dipurena conica .......... 182 

" 304. Digestive cavity of a Medusa in which the constriction has already separated the 

upper and lower halves . . . . . . . . . .182 

" 305. Adult Dipurena conica, in which the two digestive cavities are widely separated 182 

" 306. Profile view of half a young GEMMARIA GEMMOSA 184 

" 307. Profile view of GEMMARIA CLADOPHORA, magnified 184 

" 308. Quarter-disk of same, seen from the abactinal pole . . . . . .185 

" 309. Actinostome of Gemmaria, enlarged ........ 185 

" 310. Cluster of lasso-cells of the marginal tentacles . . . . . . .185 

" 311, Fertile Hydra of PENNARIA TIARELLA 187 

" 312. Medusa distended by eggs 187 

" 313. Profile view of Medusa of Pennaria tiarella . . . . . . . 187 

" 314. Different attitude of the Medusa, seen from the actinal pole 188 

" 315. Fig. 313, seen from the abactinal pole 188 

" 316. EUPHYSA VIRGULATA, seen in profile 190 

" 317. Magnified proboscis of Fig. 316 190 

" 318. Actinal view of Euphysa virgulata ......... 190 



u 



II 
II 
t( 

II 



xiv LIST OF THE WOOD-CUTS. 

Fig. 319. One of the tentacles, seen in profile 190 

" 320. Profile of ECTOPLEURA OCHRACEA, magnified 191 

" 321. The same, seen from the abactinal pole . . . . . . .192 

" 322. The same, seen from the actinal pole . . . . . . . . 192 

" 323. The base of one of the tentacles, magnified . . . . . . . .192 

" 324. Medusa of CORYMORPHA PENDULA, seen in profile. (H.J.Clark.) . . 193 

" 325. Single Hydra of HYBOCODON PROLIFER. (L. Agassiz.) 193 

326. Ilybocodon prolifer, seen from the broad side. (L. Agassiz.) . . . . 194 

327. Hybocodon prolifer, seen facing the long tentacle. (L. Agassiz.) . . .194 

328. Medusa bud of Ilybocodon prolifer. (L. Agassiz.) 194. 

" 329. Part of male community of HYDRACTINIA POLYCLINA. (L. Agassiz.) . . 198 

" 330. Part of female community. (L. Agassiz.) ....... 198 

" 331. Oil-float of NANOMIA CARA, magnified 200 

" 332. Nanomia cara, natural size 201 

" 333. Swimming-bell of Nanomia cara, seen facing the side of the straight chymiferous 

tubps 202 

" 334. The same bell, from the actinal pole 202 

335. Portion of the same bell, seen from the abactinal pole 202 

336. Same bell as Fig. 333, seen from the other side 203 

337. Group of swimming-bells in different stages of development . . ... 203 

338. Cluster of Medusas (Polyps) of first kind formed, with knob-shaped tentacles . 204 
" 339. Enlarged view of the knob of a tentacle of the first kind of Medusas . . 205 
" 340. Second kind of Medusas, with cork-shaped tentacles ...... 205 

" 341. Third kind of Medusa, having a single thread-like tentacle .... 205 

" 342. Cluster of Medusas (Polyps), in different stages of development, before the ap- 
pearance of the scale and of the tentacles ....... 206 

" 343. Knobs like those of Fig. 339, in different stages of development . . . 207 

" 344. Same kind of knob, still further developed . . . . . . . .207 

" 345. Young scale, seen from different sides ........ 207 

" 346. Youngest Nanomia found swimming on surface ....... 208 

" 347. Somewhat more advanced .......... 208 

" 348. The terminal Hydra is open, tentacles are developed as well as clusters of small 

swimming-bells ........... 209 

" 349. Still more advanced Nanomia 209 

" 350. Young Nanomia, where we find several Medusas of the first kind . . . 209 

" 351. PHYSALIA ARETHUSA Til. (L. Agassiz.) 214 

352. Bunch of single Hydras and clusters of Medusas of Physalia. (L. Agassiz.) . 215 

353. Bunch of Hydras. (L. Agassiz.) 215 

" 354. Bunch of Medusas in various stages of development. (L. Agassiz.) . . 215 

" 355. Enlarged view of one of the fertile Hydras of VELELLA MUTICA. (L. Agassiz.) 216 

" 356. Velella, seen from below, to show the Hydras. (L. Agassiz.) . . . . 216 

" 357. Magnified view of a free Medusa of Velella mutica. (L. Agassiz.) . . . 216 

" 358. Magnified view of extended Hydroids of MILLEPORA ALCICORNIS. (L. Agassiz.) 219 

" 359. Branch of Millepora alcicornis, natural size. (L. Agassiz.) . . . . .219 

360. Transverse section of a branch. (L. Agassiz.) 219 



it 
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u 



NORTH AMERICAN ACALEPH.E. 



IBLIOGRAPHY. 



AGASSIZ, L. 



ALDER, J. 



ALLMAX, J. G. 



No memoirs published previous to 1800 have been included in this list, as they can 
be found in AGASSIZ'S Bibliographia Zoologice et Geologice, and in CARUS and ENGEL- 
MANX'S Bibliotheca Zoologica. 

AGASSIZ, A. The Acalephian Fauna of the Southern Coast of Massachusetts, Buzzard's Bay ; in 

Proc. Bost. Soc. Nat. Hist., VIII. p. 224. 1861. 
" " Mode of Development of the Marginal Tentacles of the Free Medusse of some Hy- 

droids ; in Proc. Bost. Soc. Nat. Hist., IX. p. 81. 1862. 
" " Nanomia cara ; in Proc. Bost, Soc. Nat. Hist,, IX. p. 181. 1863. 

Halopsis ocellata ; in Proc. Bost. Soc. Nat. Hist., IX. p. 219. 1863. 
Contributions to the Natural History of the United States (Acalephae). Yols. HI. 

and IV. Boston. 1860-1862. 

Methods of Study in Natural History. Boston. 1863. 
Supplement to a Catalogue of Zoophytes of Northumberland and Durham ; in Trans. 

Tyneside Nat. Club, V. p. 225. 
Description of some New and Rare Zoophytes found on the Coast of Northumberland ; 

in Ann. & Mag. N. II., IX. p. 311. 1862. 

Observations on British Zoophytes ; in Edinb. New Phil. Journ., p. 144. 1862. 
Descriptions of a Zoophyte and two Species of Echinodermata new to Britain ; in 
Ann. & Mag. N. H., V. p. 73. 1860. 

On Laomedea tennis ; in Rep. Br. Ass. Adv. Sc. for 1859, p. 143. Trans. Sec. 
On the Generative Zooid of Clavatella ; in Br. Ass. Adv. Sc. for 1862, p. 100. 
Note on the Structure and Terminology of the Reproductive System in the 

Corynidae and Sertularidae ; in Ann. & Mag. N. H., VI. p. 1. 1860. 
On the Reproductive System in the Hydroidea ; in Rep. Br. Ass. Adv. Sc. 1863. 

London. 1864. p. 351. 

Note on Carduella cyathiformis ; in Ann. & Mag. N. H., VI. p. 40. 1860. 
On the Structure of Carduella cyathiformis, a Contribution to our Knowledge of 

the Lucernariadaj ; in Trans. Mic. Soc., p. 125. London. 1860. 
Notes on the Hydroid Zoophytes ; in Ann. & Mag. N. II., VIII. p. 168. 1861. 
Notes on the Phosphorescenee of Beroe ; in Proc. Roy. Soc. Edinb., IV. p. 528, 

Jan. 1862. Same in Edinb. New Phil. Journ., 1862, XV. p. 284. 
Contributions to our Knowledge of the Structure and Development of the Bero- 
ida; ; in Proc. Roy. Soc. Edinb., IV. p. 519, Jan. 1862. Same in Edinb. 
New Phil. Journ., 1862, XV. p. 287. 
On the Structure of Lucernariada; ; in Rep. Brit. Ass. Adv. Sc. for 1859, p. 143. 

London. 1860. Trans. Sec. 
On Dicoryne stricta, a new Genus and Species of the Tubularida? ; in Rep. Br. 

Ass. Adv. Sc. for 1859, p. 142. London. 1860. 

Notes on the Hydroidea. I. On the Structure of Corymorpha nutans. II. Diag- 
nosis of new Species of Tubularidaj obtained, during the Autumn of 1862, 
on the Coasts of Shetland and Devonshire ; in Ann. & Mag. N. II., Jan. 
1863, XI. p. 1. 

Notes on the Hydroidea ; in Ann. & Mag. N. II.. July, 1864. 
On the Structure of Corymorpha nutans ; in Rep. Br. Ass. Adv. Sc. for 1862, 
p. 101. Trans. Sec. 



" 



" 



<t 
u 



" 



4 BIBLIOGRAPHY. 

ALLMAN, J. G. On the Construction and Limitation of Genera among the Ilydroidea ; in Ann. 

& Mag. N. H., XIII. 1864. 

" " On some new British Tubularidse ; in Rep. Br. Ass. Adv. Sc. for 1862, p. 101. 

" " Kep. on the Reprod. Syst. in the Hydroidea; in Rep. Br. A. A. S. f. 18G3, p. 351. 

" " On the Occurrence of Amsebiform Protoplasm, and the Emission of Pseudopodia 

among the Hydroidea ; in Ann. & Mag. N. II. March, 18G4. 
BENEDEN, J. P. VAN. On the Strobilation of the Scyphistomata ; in Ann. & Mag. N. II., 18GO, 

V. p. 504. From Acad. Belg. 
BOECK, CHR. Beskrivelse over en Tubularie fra Belsund paa Spitzbergen, Tubularia regalis, in 

Forhandl. Vid. Selsk. (Aar 1859.) Christiania. 1860. pp. 59, 66, 151. 

BRONX, H. G. Die Klassen u. Ordnungen des Thier-Reichs (Actinozoa). Leipzig u. Heidel- 
berg. 1860. 
BUSK, G. On a new Hydroid Polype belonging to the Genus Cordylophora AIL, discovered by 

Senator Kirchenpauer of Ritzebiittel ; in Mic. Jour., p. 283. 1861. 
CLAPAREDE, A. R. E. BeitrJige zur Fauna der Schottischen Kiiste ; in Zeits. f. Wiss. Zool., X. 

p. 401. 1860. 
Beobachtungen iiber Anatomic u. Entwickelungsgeschichtc Wirbelloser 

Tliiere. Leipzig. 1863. 

" " in Bibliog. Univ. tie Geneve, XV. p. 150. 1862. 

CLAUK, H. J. Lucernaria, the Coenotype of Acaleplue ; in Proc. Bost. Soc. N. II., p. 47. 1862. 
" " Prodromus of the History, Structure, and Physiology of the order of Lucernarire ; 

in Journ. Bost, Soc. Nat. Hist., VII. 1863. 

" " Lucernaria, . . . . ; in Am. Journ. Arts and Sciences, May, 1863. 

" " " . . . . ; in Ann. & Mag. N. II., XII. p. 19. 1863. 

" " in Agassiz's Contrib. Nat. Hist. U. S., Vols. III. and IV. passim. 

" " Tubularia not Partlienogenous ; in Am. Journ. Arts and Sciences. Jan. 1864. 

CLAUS, C. Neuc Beobachtungen iiber die Structur u. Entwickelung der Siphonophoren ; in Zeit. 

f. Wiss. Zool., XII. p. 536. Jan. 1863. 
" " Ueber Physophora hydrostatica, ncbst Bemerkungen iiber andere Siphonophoren ; in 

Zeit. f. Wiss. Zool., X. p. 8. 1860. 
DAWSON, J. "W. Zoological Classification, or Coelenterata and Protozoa versus Radiata ; in Can. 

Nat. & Geol., VII. p. 438. 
" " Elementary Views of the Classification of Animals ; in Can. Nat. & Geol., 

Aug. 1864. 

EDWARDS, II. MILNE et HAIME, J. Histoire Naturclle des Coralliaires, T. III. Paris. 1860. 
FULLER, C. B. In Journ. Portland Soc. N. H., I. pp. 64, 91. 1862. 

u " Report on Marine Zoology ; in Second Annual Report Nat. Hist. & Geol. of the 

State of Maine, p. 129. 1863. 
GEGENBAUR, C. Neue Beitriige zur Niiheren Kenntniss der Siphonophoren ; in Nova Acta Acad. 

Nat. Cur. 1860. 

GOSSE, P. H. Evenings with the Microscope. New York. 1864. 
" " The Blue Cyanea ; in Intellectual Observer, Oct. 1863. 

" On the Lucernaria cyathiforinis of Sars ; in Ann. & Mag. N. H., V. p. 480. 1860. 

GREENE, J. R. Manual of the Sub-kingdom Coelenterata. London 1861. 

" " Recent Contributions to the Literature of the Sub-kingdom Ccelenterata ; in Nat. 

Hist. Rev., I. 1861. 

" " Review of Agassiz's Contrib. to Nat. Hist. U. S. ; in Nat. Hist. Rev. III. 1863. 

" " On Sertularia tricuspidata, and on the Genus Huxleya ; in Ann. & Mag. N. H., 

V. p. 431. 1860. 

" " A "Word on Embryology, with Reference to the Mutual Relations of the Sub- 

kingdoms of Animals; in Rep. Br. Ass. Adv. Sc., p. 132. 1860. Trans. Sec. 
GRUBE, E. Ausflug nach Triest u. clem Quarnero. Berlin. 1861. 
HINCKS, THOS. On New Australian Hydrozoa ; in Ann. & Mag. N. II., VII. p. 279. 1861. 

On the Production of similar Medusoids by certain Hydroid Polypes belonging to 

different Genera; in Rep. Br. Ass. Adv. Sc. f. 1862, p. 107. Trans. Sec. 
" " On Clavatella, a new Genus of Corynoid Polyps, and its Reproduction ; in Ann. 

& Mag. N. II., VIII. p. 73. 1861. 

" A Catalogue of Zoophytes of South Devon and South Cornwall ; in Ann. & 

Mag. N. II., VIII. pp. 172, 251, 290, 360. 1861. 



BIBLIOGRAPHY. 5 

HIXCKS, THOS. Catalogue of Zoophytes of South Devon and South Cornwall ; in Ann. & Mag. 

N. II., IX. pp. 22, 200, 303, 467. 1862. 

" " On the Production of. Similar Gonozooids by Hydroid Polyps belonging to dif- 

ferent Genera ; in Ann. & Mag. N. II., X. p. 459. 1862. 
" " Catalogue of the Zoophytes of South Devon and South Cornwall ; in Ann. & 

Mag. N. H., X. p. 360. 1862. 

" " On some new British Hydroids ; in Ann. & Mag. N. H., XI. p. 45. 1863. 

" " On the Development of the Hydroid Polyps, Clavatella and Stauridia, with 

Remarks on the Relation between the Polyp and the Medusoid, and between 
the Polyp and the Medusa; in Rep. Brit. Ass. Adv. Science, p. 145. 1861. 
Trans. Sec. 

HODGE, GEO. Contributions to the Marine Zoology of Seaham Harbor. Occurrence of Cory- 
morpha nutans at Seaham ; in Trans. Tyneside Nat. Field Club, V. Pt. II. 
p. 78. 1861. 
" " On a new Hydroid Zoophyte (Podocoryne Alderi) ; in Trans. Tyneside Nat. Field 

Club, V. Pt. U: p. 82. 1861. 

HOUGHTOX, W. On the Hydra rubra of Mr. Lewes ; in Ann. & Mag. N. II., V. p. 228. 1860. 
HUXLEY, THOS. H. Elements of Comparative Anatomy. London. 1862. 
JAGER, G. Ueber das spontane Zerfallen der Siisswasserpolypen nebst einigen Bemerkungen 

iiber Generationswechsel ; in Sitzb. d. Akad. Wien., XXXIX. p. 321. 1860. 
JOURDAIX. Note sur les organes genitaux de la Cyanca aurita Cuv. ; in Comptes Rendus, Vol. 

LV. p. 834. 1862. 

KEFERSTEIX, W. Untersuchungen ueber niedere Seethiere ; in Zeits. f. Wiss. Zool., XII. p. 1. 

June, 1862. I. Ueber die Gattung Lucernaria 0. F. Mullcr ; in Zeits. f. 
"\Yiss. Zool., XH. p. 1. II. Ueber einige Quallen ; in Zeits. f. Wiss. Zool., 
XII. p. 26. 
" " u. EIILERS, E. Auszug aus den Untersuchungen vom Mittelmeer ; in Wieg- 

mann's Archiv, 1860. I. p. 324. 

" " Same in Naehricht. der Univ. u. Ges. d. Wiss. Gottingen, No. 23, p. 25. 1860. 

KIRCHEXPAUER. Die Seetonnen der Elbmiindung. Ein Beitrag zur Thier u. Pflanzen Topo- 
graphic ; in Abhandl. d. Naturh. Yereins, IY 3 . Hamburg. 1862. 
KROHX, A. Beobachtungen iiber den Ban u. die Fortpflanzung der Eleutheria Quatref.; in 

Wieg. Archiv, 1861. I. p. 157. 
" Observations on the Structure and Reproduction of Eleutheria Quatref. ; in Ann. & 

Mag. N. H., IX. p. 1. 1862. 
LACAZE-DuTniERS, H. Embryogenie des Rayonnes, Reproduction geneagenitique des Porpites ; 

in Comptes-Rendus, LV. p. 851. Nov. 1861. 

" On the Reproduction of Porpita; in Ann. & Mag. N. H., p. 186. 1862. 

LEUCKART, R, Bericht ueber die Leistungen in der Naturgeschichte der niederen Thiere ; in 

Archiv fur Nat, 1860-1863. 

LEWES, G. H. New British Species of Hydra ; in Ann. & Mag. N. H., V. p. 71. 1860. 
LUTKEX, CIIR. F. Forvandlingerne i Dyrei-iget ; in Tids. for pop. Freni. af Nat. 1861-62. 
McAxDREW, R. List of the British Marine Invertebrate Fauna ; in Rep. Br. Ass. Adv. Sc., 

p. 217. 1860. 

METTEXHEIMER, C. Ueber die Gesichtsorgane des violetten Seesterns, nebst Beobachtungen 
iiber die Ohrenqualle u. Versuchen iiber die Motilitiit derselben ; in Archiv f. Anat. u. 
Phys., p. 214. 1862. 
MEYER, A. u. MOBIUS, K. Kurzer Ueberblick der in der Kieler Bucht von uns beobachteten wir- 

bellosen Thiere, als Vorliiufer einer Fauna derselben ; in Archiv f. Nat,, 1862. I. p. 229. 
MULLER, FR. Cunina Kollikeri F. Milll. ; Beitrag zur Naturgeschichte der JSginiden ; in Archiv 

f. Nat., I. p. 42. 1861. 
" " Polypen ii. Quallen v. Santa Catharina, Olindias sambaquiensis ; in Archiv f. Nat., 

1861. I. p. 312. 
" " Ueber die Angebliche Bilateralsymmetrie der Rippenquallen ; in Archiv f. Nat., 

1861. I. p. 320. 

" " Ueber die System. Stellung der Charibdeiden ; in Archiv f. Nat., 1861. I. p. 302. 

" " On the Systematic Position of the Chai'ibdeida? ; in Ann. & Mag. N. H., X. p. 6. 1862. 

" " Ueber die Ursache der Strbmungen in der Leibeshble der Sertularien ; in Archiv 

f. Nat,, I. p. 34. 1863. 



6 BIBLIOGRAPHY. 

MURRAY, A. Descriptions of New Sertularidae from the California!! Coast ; in Ann. & Mag. 

N. H., V. p. 250. 1860. 

" On Sertularia tricuspidata ; in Ann. & Mag. N. II., V. p. 504. 18GO. 
NORMAN, A. M. On Undescribed British Hydrozoa, Actinozoa, and Polyzoa ; in Ann. & Mag. N. 

II., XIII. p. 82. Jan. 18C4. 

" " On the Crustacea, Echinodermata, and Zoophytes obtained in a Deep-Sea 

Dredging, off" the Shetland Islands in 1861 ; in liep. Br. Ass. Adv. Sc., 
p. 151. 1861. Trans. Sec. 
PACKARD, A. S. JR. A List of Animals dredged near Caribou Island, Southern Labrador ; in 

Canadian Nat. & Geolog. Dec. 1863. 

PAGENSTECHER, II. Untersuchungen u'ber niedere Seethiere aus Cette ; VIII. Zur naheren 
Kenntniss dcr Vellelidenform Rataria, nebst Betrachtungen uber die Velleliden im Allge- 
meinen ; in Zeits. f. Wiss. ZooL, XII. p. 406. Jan. 1863. 
PEACH, C. W. On the Zoophytes of Caithness; in Rep. Br. Ass. Adv. Sc., p. 155. 1859. 

Trans. Sec. 

PETERS, W. C. H., CARUS, J. V., & GERSTAECKER, C. E. A. Ilandbtich der Zoologie- Leip- 
zig. 1863. 
PRICE, JOHN. On the Genus Cydippc ; in Rep. Br. Ass. Adv. S. 1859, p. 155. London. 1860. 

Trans. Sec. 

QUATREFAGES, A. DE. Metamorphoses de 1'homme et des animaux. Paris. 1862. 
SAKS. M. Ueber das Ammengeschlecht Coryrnorpha und seine Arten, nebst den von diesen aufge 

ammten Medusen ; in Archiv f. Nat., 1860. I. p. 341. 
" " Bemaerkninger over norske Coelenterater ; in Vidensk. Selks. Forh., p. 140. Chris- 

tiania. I860. 
" " Tegninger af og Oplysninger om nogle Coelenterater fra Norges Kyster ; in Skand. 

Naturf. Mode i Kjobenhavn. 1860. p. 690. 
" " On the Nurse Genus Coryrnorpha and its Species, together with the Medusae produced 

from them ; in Ann. & Mag. N. H., VIII. p. 353. 1861. 

" " Bemaerkninger over d. norske Hydroider ; in Videns. Selks. Forhand. 1862. 
" " Geologiske og zoologiske Jagttagelser anstillede paa en Reise i en Deel af Trondhjems 

Stift. Christiania. 1863. 

SIEBOLD, K. TH. v. Ueber Parthenogenesis. Miinchen. 1862. 
SEMPER, K. Reisebericht von Di\ Karl Semper, Brielliche Mittheilung, an A. Kolliker ; in Zeits. 

f. Wiss. Zool., X. p. 558. 

STEEXSTRUP, J. B. Om de ved Norges Kyst forekommendc Arter af Slaegten Lucernaria ; in 

Forhand. Vid. Selsk. i Christiania, Aar 1860. Christiania. 1861. p. 145. 
" " Bidrag til Kundsab om de nordiske Lucernarier ; in Vidensk. Med. 1859, 

p. IOC. Kjobenhavn. 1860. 

TROSCHEL, F. II. Ilandbuch der Zoologie. Berlin. 1864. 6 te Auflage. 

VERRILL, A. E. List of Polyps and Corals sent by the Museum of Comparative Zoology to other 
Institutions in Exchange, with Annotations ; in Bulletin Museum Comparative Zoology, 
No. 3. Cambridge. 1864. 
WRIGHT, T. S. On the Reproduction of Thaumantias inconspicua ; in Quart. Journ. Mic. Scien., 

p. 221. 1862. 
" " Observations on British Zoophytes and Protozoa ; in Edinb. New Phil. Journ., 

XVI. p. 154. 18C2. 

" " Observations on British Zoophytes ; in Quart. Journ. Mic. Scien., p. 45. 1863. 

" " On the Reproduction of ^Equorea vitrea ; in Edinb. New Phil. Journ., XV. p. 

144. 1862. 
" " Observations on British Protozoa and Zoophytes ; in Ann. & Mag. N. II., VIII. 

p. 120. 1861. 
" " On Hermaphrodite Reproduction in Chrysaora hyoscella ; in Ann. & Mag. N. II., 

VII. p. 357. 1861. 
" " Observations on British Zoophytes and Protozoa ; on Atractylis coccinea ; in 

Edinb. New Phil. Journ., XIV. p. 150. 1861. 
WOOD, W. In Journ. Portland Soc. Nat. Hist., I. p. 63. 1862. 



NORTH AIEKICAN ACALEPHJE. 



OEBEE CTENOrilOR/E ESCH. 

Clrnopliorcc Escn. Syst. der Acalcphen, p. 20. 1820. 
Ctenoplione GKGEXBAUK. Archiv. f. Natur^., 1856. I, p. 1G3. 
Ctfnophone Ac; ASS. 18GO. Cont. Nat. Hist. U. S., III. p. 289. I860. 
Ciliof/radex BLAINV. Man. d'Actin., p. 143. 1830. 
Beroides LESS. Zoopb. Acal., p. 01. 1843. 

The affinities of the Ctenophorai have become one of the most fertile 
topics of discussion among recent investigators. Vogt, following Quoy, 
removes them from the Acalephs altogether. Huxley places them in 
close proximity to Polyps. Clark has made a special class of them, 
equivalent to Echinoderms, while Milne Edwards and Agassiz, after a 
careful revision of the whole subject, have followed Cuvier and Esch- 
scholtz, and retained them as an order of Acalephae. These various views 
of the true relations of the Ctenophorse are based upon very different 
grounds, and are urged with more or less force in accordance with the 
degree of importance attached by investigators to the details of struc- 
ture upon which they separate the Ctenophorre from the Acalepho?, and 
refer them to other classes of the Animal Kingdom ; the apparent bilat- 
erality so strongly developed in some of the families (as Cestum, Bolina, 
and Mertensia) being urged by Vogt as the principal ground for re- 
moving them from Acalephs, and associating them with the Mollusks ; 
while Huxley places them with Polyps on the ground of the special 
structure of their digestive cavity ; and Clark simply states his belief 
in their separation as a class, without furnishing us any proofs. We 
are able to throw new light on this question by a series of facts derived 
from their embryological development, hitherto unnoticed. As the ob- 
servations of Dujardin on the development of Coryne gave us the key 
which led to the ultimate separation of the Hydroids from the Polyps, 
so I hope to be able to show that the development of the Ctenophorse 
gives us a true insight into the disputed affinities of these animals. 

Before the publication of the valuable observations of McCrady on the 
development of a species of Bolina, little was known of their embryology 
except the mere fact, derived from the few casual observations of Miiller, 
Wright, Boeck, and Price, that the Ctenophoree were probably all repro- 



8 CTENOPHOR^E. 

duced from eggs, and that at an early age they gave unmistakable 
signs of their parentage. McCrady's observations showed us how great 
were the changes of figure their young undergo before they assume 
the aspect of the parent. It has been my good fortune to trace these 
changes in several of our species of Ctenophorae somewhat in detail, 
and I shall make use of the material thus afforded in discussing the 
position of these animals, as well as their pretended bilaterality, and, 
by comparing their mode of development with that of Polyps, Acalephs, 
and Echinoderms, endeavor to ascertain whether their association with 
them into one great branch of the Animal Kingdom is true to nature, 
or whether the affinities between the mode of execution in the plan of 
the members of the Ccelenterata are really of such a character as to 
justify their separation from the other Radiates as one great branch 
of the Animal Kingdom. 

Let us first examine the character of the Coelenterata and of the 
Radiata as they are understood. What is common to Polyps, Acalephs, 
and Echinoderms is a vertical axis, or rather an axis through which 
we can pass a plane at right angles, and in this plane draw two axes 
at right angles to each other. These axes, of course, are not equally 
prominent in Polyps, Acalephs, and Echinoderms ; taking, for instance, 
the three axes as we find them in some of the Spatangoids, we have a 
vertical axis, a coeliac axis, and a diacoeliac axis, the mouth and anus 
being placed in such a position with reference to the coeliac axis as to 
give us a right and left, an anterior and a posterior extremity. In the 
Acalephs, it is only among the Ctenophorre that we can distinguish 
between the coeliac and diacoeliac ; but we have neither right nor left 
no anterior or posterior side ; while in Polyps we can distinguish 
their axes with greater exactness than in the Hydroids and Discophorse. 
We are so accustomed to impose our notions of symmetry on every- 
thing w r e meet, that it is difficult to divest ourselves of the idea that 
every animal has not necessarily a right and a left side, an anterior and 
a posterior extremity ; we start with the idea that such relations must 
exist in all animals, however disguised, and under this impression we 
try to reconcile plans which are totally distinct. If, however, we admit 
the idea of different plans as the foundation of animal life, we must 
give up all attempt to find some passage from one to the other. Ani- 
mals the equation of which could be represented by that of a sphere, 
or by that of two parallel planes, or of a series of cylinders, or of two 
parallel cylinders, can never pass from one to the other ; the equation 
of a sphere cannot be transformed into that of a plane, nor into a 
cylinder ; the equations representing each of these figures include, it 
is true, all the possible spheres or all the possible cylinders which may 
be constructed by changing the values of the variables, but can never 
be transformed one into the other. The infinite variety of forms, and 



CTENOPIIORvE. 9 

apparently aberrant types, constantly met with among animals, has 
been the main cause of our difficulty in referring them to their proper 
plan. It is not always an easy matter to reduce an equation to its 
simplest form, and find out what it is ; it may be concealed by coef- 
ficients which will disappear only after repeated operations, and then 
only enable us to determine of what degree the equation is. These 
coefficients in an equation may be compared to the modifications of 
those parts which appear to affect the mode of execution in animals ; 
and it may not always be an easy matter nor a possible one, in the 
present state of our knowledge, to solve these organic equations. The 
history of Science is full of examples of this kind ; and we may have 
to discover new methods in Natural History, as well as in Mathematics, 
before we can proceed with our eliminations, or arrive at a solution. 
Thus the plan of radiation may be so carried out, by a modification 
of some of the parts, as to appear at first sight to be bilateral ; but 
analyze these modifications carefully, and beneath them all can be 
traced the plan of radiation, hidden only by external features of bilater- 
ality. Such is eminently the case in the larva? of Echinoderms, and to 
a less degree in the imitations of Echinoderm larva), the Ctenophorre. 
Bilaterality seems at first sight to be the plan upon which these animals 
are built ; but an elimination of the deceptive coefficients will show the 
plan of radiation underlying this apparent bilaterality. 

The figures here given of very young Ctenophora) show no indica- 
tion of this bilaterality, at least no more than can be traced in any 
four-rayed jelly-fish. The tubes are as yet all of equal size, no promi- 
nence is given to one side over the other, and the only hint of bilater- 
ality is the early distinction of the longitudinal and of the transverse 
axis by the position of the tentacles. No lateral appendages develop- 
ing into immense lobes, as in the adults, can as yet be detected. The 
characteristic feature of the eggs of the Ctenophoras is the great diam- 
eter of the envelope compared to the yolk, which is hardly more than 
one third the diameter of the egg. The whole yolk is transformed by 
segmentation into the embryo ; this at an early period assumes a very 
slightly pear-shaped form, and is moved by means of a few pairs of 
large locomotive combs, equalling in length the diameter of the em- 
bryos. This is the first indication we have that the embryo is a Cteno- 
phore ; and the early stages are marked by the constant and violent 
Happing of the combs, arranged in four bunches near the abactinal 
pole, immediately at the base of the large eye, also disproportionately 
large in the young, containing but few granules, and seeming almost 
like a glass ball fastened to the top of this active embryo. During this 
stage the young Ctenophore is moving about somewhat slowly within 
the envelope of the egg. With increasing age the locomotive flappers 
descend somewhat along the spheromeres, and we find at the opposite 

NO. II. 2 



10 CTENOPHOR.E. 

extremity from the eye the first trace of a small cavity (the digestive 
cavity of the adult), which increases in size till it becomes spherical. At 
about this time there is found, between the four clusters of the locomo- 
tive flappers, a second cavity, which has at first no connection whatever 
with the digestive cavity, and develops independently of it. This sec- 
ond formed cavity, now a large rectangular bag, slightly lobed between 
each of the four clusters of locomotive flappers, is the chymiferous 
cavity, from which the funnel and the chymiferous tubes take their 
origin in somewhat older stages. With advancing age the walls of the 
two cavities become more circumscribed, and at the same time more 
clearly defined, approaching each other constantly, until finally they 
open into each other. The digestive cavity and the chymiferous tubes 
diminish in diameter, becoming more circumscribed, and losing little by 
little the character of broad pouches for that of narrow tubes, extending 
through the gelatinous mass. The locomotive flappers extend with the 
chymiferous tubes along each one of the four pouches, which have 
given rise to two chymiferous tubes, one long and one short one, devel- 
oping independently. This difference is barely perceptible in the adult 
Pleurobrachia ; it is well marked in Mertensia, still better in Idyia, 
quite prominent in Lesueuria, and takes its greatest development in 
Bolina, where adjoining tubes anastomose after almost endless windings 
through the large lobes formed by the lateral projections of the gelati- 
nous mass. The cause of the predominence of some of the sphero- 
ineres over the others, is the unequal development of these two sets of 
tubes, which may or may not extend into lobes, thus giving to the 
Ctenophora3 the appearance of bilateral animals. But examine this 
same development in another class of Radiates, among the Echino- 
derms, in the Spatangoids, for instance, where the odd ambulacrum is 
the one which takes the least development, when the other four are 
more equally developed, and no one will for that reason forget their 
radiate character, and call them strictly bilateral animals. 

We can thus distinguish, among Spatangoids, an anterior and a poste- 
rior extremity, a right and a left side. In Ctenophoree, owing to the 
peculiar manner in which the difference between the chymiferous tubes 
is developed, we are enabled to distinguish simply two diameters, but 
not an anterior and a posterior extremity, or a right and a left side ; it 
seems, therefore, scarcely logical to call these animals bilateral, when in 
reality they show less sign of bilaterality than the Spatangoids, which 
no one, except Huxley, seems to doubt belong to Radiates.* The axes 
we can thus distinguish among the Ctenophora? by the unequal devel- 
opment of the chymiferous tubes, would not enable us to decide whether 
the long tubes of the different genera were the same tubes developed 
more fully in the different species. For instance, we should at first 

* See analysis of this view in Agassiz's Contributions, Vol. V. p. 60, by A. Agassiz. 



CTENOPHOR^E. 

sight suppose the long tubes of Pleurobrachia, of Mertensia, of Idyia, of 
Bolina, of Lesueuria, to be homologous, but such is not really the case ; 
and the only means we have of determining this is the plane passing 
through the tentacles, enabling us to ascertain whether the longitudinal 
axis is in the trend, or at right angles to that plane. We shall soon see 
that in Pleurobrachia and Mertensia the plane, including the tentacles, 
passes through the long axis, while in Bolina and Lesueuria it passes 
through the short axis ; that the long tubes are on each side of the ten- 
tacles, and consequently that the long tubes of Mertensia and the long 
tubes of Bolina are not homologous ; but what corresponds strictly to 
the long tubes of Pleurobrachia and Mertensia are the short tubes 
placed on each side of the tentacular system. The lateral tubes invari- 
ably in the plane of the tentacular system give us the means of deter- 
mining to which of these two classes Idyia belongs, and we find that 
its longitudinal axis corresponds with that of Bolina, the lateral tubes 
being in the shorter axis, as in the last-named genus, while in Pleuro- 
brachia, as in Mertensia, they are in the longer axis. Such is the origin 
of the characters which give to some members of the Ctenophorse their 
remarkable bilateral appearance. It is simply a modification of what is 
perfectly familiar to us among Echinoderms, and especially among the 
Spatangoids ; but owing to the bilateral character of their develop- 
ment, the Ctenophorse make us lose sight entirely of the original radi- 
ate plan upon which these animals are built. Viewing, however, this 
differentiation of the axis in all its stages, as we find it in Pleurobra- 
chia, in Idyia, in Mertensia, in Lesueuria, in Bolina, we constantly keep 
before our eyes the original formula from which the other members are 
derived. 

Examined in the light of prophetic beings, the bilaterality of the 
Acalephs is but another of those wonderful links which unite in one 
great whole the different members of the Animal Kingdom. As the 
Polyps are the prophetic representatives of the Acalephs in their em- 
bryonic condition, the Hydroid state, so must we look at the Ctenophorse 
as the prophetic type of those still more wonderful beings, the Echino- 
derm larva?, in which bilateral symmetry is carried to such an extent 
that even the great mind of a Miiller is led to consider them as exhibit- 
ing a direct passage from a bilateral to a radiate plan of structure. In 
the bilateral symmetry of the Ctenophoroa we are constantly reminded 
of the general appearance of Echinoderm larvce, in which the radiate 
structure should still be so far apparent as not to be concealed by the 
bilateral symmetry. 

Looking at the Ctenophorae as prophetic animals, we are able to 
understand the separation of the digestive cavity into two distinct 
parts. It is only what we find more fully developed in the Echino- 
derm larvae ; the separation of a sort of alimentary canal, in Ctenophorce, 



12 CTENOPHORvE. 

from the rest of the digestive apparatus, exactly corresponding to what 
exists in Echinoderm larvae. The connection between the water system 
and the digestive system is likewise precisely similar to that of Echino- 
derms in their larval state ; for although in the adult Star-fish, or Sea- 
urchin, or Ophiuran, there is no apparent connection between the am- 
bulacra! and the digestive system, yet in the young larvae we can see 
that this connection exists, the water system being formed by diver- 
ticula from the digestive cavity ; while the injections of Professor Agas- 
siz have proved the existence, in the adult, of a similar connection in 
Echinarachnius, in Mellita, and in Clypeaster. 

It was only after the embryos of Echinoderms had been compared 
with Ctenophoroe that undoubted evidence of their identity of plan was 
obtained. The embryological development of Ctenophoroa leaves no 
doubt as to the Acalephian character of the order. It remains only for 
us to see whether the Ctenophora3 form a group of equal value with the 
rest of the Acalephs, or stand simply as an equivalent of the other two 
orders, the Discophorae and the Hydroids. The careful examination 
lately made of many genera of which we had no definite knowledge 
before, as well as their embryology, has now left it difficult to decide 
whether the Discophorae and Hydroids are independent orders, or wheth- 
er the distinction established between the Discophorne and Hydroids is 
merely a subordinal division in a great order, including these two. If 
so, this order might be called the Medusido?, in opposition to the Cteno- 
phoro?, which are an order perfectly and accurately circumscribed ; the 
presence of locomotive flappers being as characteristic for the Cteno- 
phorne, and as constant a feature of Ctenophorrc among Acalephoe, as 
feathers are for the class of Birds among Vertebrates. These flappers 
exist almost from the earliest embryonic stages, and thus far not a 
single exception is known to the rule. Fritz Miiller and Agassiz have 
shown that it is hardly natural to associate the Charibdeidce and JEg'i- 
nidoe with the Hydroids, and the latter has proposed to unite them with 
DiscophonB, while the former would make a separate order of them. 
This seems hardly justifiable, as there are as many reasons their mar- 
ginal appendages, genital organs, c. for uniting them with Disco- 
phorae, as for leaving them with the Hydroids, the shape of the bell, 
the great development of the veil. If, in addition, we take into account 

what we have observed in the Trachvnemidoe, it will be seen that we 

/ 

can no longer draw the line between the Discophorae and Hydroids as 
distinctly as before ; while the creation of a third group equivalent 
to these two, to contain the families in dispute, does not bring us any 
nearer to the solution of the problem. A more accurate knowledge of 
the tropical forms will go far to settle this point ; and in the mean 
while, with this explanation, I will place temporarily (until further 
information can be gained) the ^Eginida) and the Trachynemidse among 



CTENOPHOR^E. 13 

the Discophoroe, with the full expectation that future researches will 
give us better reasons than we have at present for abandoning, as con- 
trary to nature, two orders which have thus far been almost universally 
acknowledged by all investigators of Medusae. If the Discophorae are 
to be united with the Hydroids, we shall have to divide the Acalephs 
into two orders, Ctenophorae and Medusidae ; the different suborders of 
the latter division including all the suborders of the Discophorre of 
Eschscholtz, and those of the Hydroids as limited by Professor Agassiz. 

The remarkable changes of form the Ctenophorae undergo until they 
attain their adult state, will necessitate at no very distant time a com- 
plete revision of the Ctenophorse, as soon as the embryology of a suffi- 
cient number of families has become well known. What is now espe- 
cially wanting is an embryology of Cestum, which would give us, with 
what has been shown here of the embryology of the three other sub- 
orders of Ctenophorse, a standard for an embryological classification of 
the Ctenophorre. We can already see that many of the genera of 
Eschscholtz (Medea and Pandora], as has already been suggested by 
Professor Agassiz and by McCrady, are only embryonic stages ; all such 
species as the Cijdippe qiiadricostata of Sars (BoUna norvegica), the 
Cydl-ppe brevicostata of Will (Ckiaja multicornis M. Edw.), and the 
Sicyosoma rutilum of Gegenbaur, are undoubtedly undeveloped stages 
of some of the well-known Ctenophorce of the Northern Ocean, the 
Adriatic, and the Mediterranean. From what has been shown of the 
transformations of Bolma alata, I should even be inclined to consider 
the Cydippe hormiphora of Gegenbaur as one of the stages of growth 
of Euramphaxi vexiUigera Gegenb. It seems to me that there is be- 
tween these two species the same relation which exists between some 
of the stages here figured of Bolma alata. The material at my com- 
mand is too imperfect to attempt anything more definite than the few 
hints here thrown out for more fortunate observers. 

Professor Agassiz, in his third volume of the Contributions, intended 
to give an embryology of some of our species of Ctenophora?. He 
made many observations previous to 1856, which, however, were never 
noted down ; only a couple of sketches of a young Pleurobrachia were 
drawn by Mr. Sonrel ; and during the subsequent summers other and 
more pressing work compelled him to forego his intentions. The ob- 
servations here presented, in the descriptions of our common species, 
were made independently during the summers of 1860 - 63. 



14 LOBAT^E. 



SUBORDER LOBAT^E ESCH. 

Lobataz ESCH. Isis., p. 741. 1825. 

Lobatce AGASS. Cont. Nat. Hist. U. S., III. p. 289. 1860. 

Mnemiidce ESCH. Syst. d. Acalephen, p. 29. 1829. 

In the Lobatae we find that the diameter passing through the ten- 
tacular apparatus is invariably the smaller, while the compression of 
the spherosome is in the plane at right angles to it. This is reversed 
in the Saccatae. The spheromeres at the extremity of the longer trans- 
verse axis, the coeliac axis, develop into lobes. 



Family BOLINID^E Agassiz. 

Bolinidce AGASS. Cont. Nat. Hist. U. S., HI. pp. 200, 289. 18CO. 

The family of Bolinidae has here a somewhat different circumscrip- 
tion from that ascribed to it by Professor Agassiz in his " Contribu- 
tions." The genus Lesueuria, of which no species was known on our 
coast in 1860, has been removed from the Mnemiidae to the Bolinidae. 
It is evident from the description hereafter given of Lesueuria, that 
this genus is only a Bolina with diminutive lateral lobes. The genus 
Mnemiopsis also is shown to belong to the Bolinida3, and not the 
Mneinidaa. 

BOLINA MEET. 

Bolina MEET. Mem. Acad. St. Petersb., H. p. 513. 1833. 
Bolina AGASS. Mom. Am. Acad., IV. p. 349. 1849. 
Bolina AGASS. Cont. Nat. Hist. U. S., III. p. 249. 1860. 
Mnemia SARS (non Esch.). Beskriv., p. 32. 1835. 
Alcinoe LESS, (iwn Rang). Zooph. Acal., p. 88. 1843. 
Anais LESS. Zooph. Acal., p. 101. 1843. 



Bolina septentrionalis MEET. 

Bolina septentrionalis MERT. (non Agass.). Acad. St. Petersb., p. 515, PI. VH. 1833. 
Bolina septentrionalis LESS. Zooph. Acal., p. 83. 1843. 

Off Matthaei Island, Behring's Straits (Mertens). 



BOLINA ALATA. 15 



Bolina alata AGASS. 

Bolina alata AGASS. Mem. Am. Acad., Vol. IV. Pt. 2, p. 349, Pis. 6, 7, 8. 1849. 

Bolina alata AGASS. Cuntrib. Nat. Hist. U. S., Vol. III. pp. 249, 289. 

A/fi/niif rcniiicularis GOULD (-non Rang). Inverteb. of Mass., p. 349. 1841. 

Bolina alata STIMPS. Mar. Inv. Grand Manan, p. 11. 1853. 

Bolina alata PACKD. A List of Animals dredged near Caribou Island, Can. Nat. & Geol. 1SG3. 

It is quite remarkable that there should be no mention made by 
Fabricius of a single Ctenophore which may be identified with any 
species of the genus Bolina. There is hardly a more common Medusa 
than the Bolina alata of our coast ; and the occurrence of so many of 
our species of Ctenophorae on the coast of Greenland makes the ab- 
sence of Bolina the more striking, and quite interesting in a geograph- 
ical point of view, as we should thus have among Acalephs a case of 
geographical distribution analogous to that of Echinarachnius, which 
does not extend farther north than Labrador. 

To the description of the adult given by Professor Agassiz I have 
nothing of importance to add, with the exception that the chymiferous 
tubes which run along the edge of the lateral lobes, when seen from 
the narrow side, should unite, and thus complete the circuit (Fig. 16), 
instead of stopping short at a little distance apart, as they have been 
represented by him. This connection takes place at an early period of 
the development. (See Fig. 8.) 

The compression of the spherosome of Bolina and of Pleurobrachia 
is in different planes, otherwise it would be exceedingly difficult to 
distinguish a very young Pleurobrachia from a young Bolina. In the 
young Bolina, as has been shown already by McCra- 
dy, we find long tentacles ; so that the younger stages 
of this Medusa are so unlike the adult, that it would 
be the most natural error to commit, to consider it 
the young of Pleurobrachia. The accompanying fig- 
ures (1-3) are taken immediately after the escape of 
the young from the egg. It will be noticed, when compared to Pleuro- 
brachia, that besides the position of the tentacular organ, the outline of 
the spherosome is somewhat different, and that the ambulacra are quite 
narrow. The digestive cavity also fills a comparatively small space. 
(Fig. 2.) The extreme tenuity of the tubes soon becomes a character 
by which the young Bolina is at once distinguished from the young 
Pleurobrachia, as well as its ellipsoid shape, which greatly increases 

In all the young Ctenophorse the following lettering has been adopted : f/, digestive cavity ; 
o, anal rosette ; 7, tentacle ; c, long ambulacral tube (longitudinal ambulacra) ; c', short ambulacra! 
tube (lateral ambulacra) ; e, eye speck ; /, funnel ; , ambulacral cavity ; /, lateral tubes, c' is the 
longest tube at first, and c the shorter ; n, lobes of spherosome ; the names are taken from the adult. 

Fig. 1. Young Bolina, seen from the narrow side. 




16 



BOLIXA ALATA. 



with age. (Fig. 4, which is Fig. 6 seen from abactinal side.) We soon 
perceive in the young of this species changes of shape similar to those 
to be described in Idyia and Pleurobrachia : the outline becomes more 
elongated ; the lateral tubes, at first simple diverticula from the main 



Fig. 2. 



Fig. 3. 



Fig. 4. 







ambulacra! tubes (I, Fig. 5), extend to the level of the opening of the 
mouth (Fig. 6). We can also trace a difference in the rapidity of 
growth of the ambulacral tubes, but, contrary to what we find in 
other genera, we observe the tentacular ambulacra are the most rapid 

in their growth. When 

Fig - 6 - Fig - 7 - they reach the bottom of 

the spherosome, they bend 
towards each other (Fig. 
7), and finally join (Fig. 8), 
but have at present no 
connection with the lat- 
eral tubes near the mouth. 
It will be noticed by the 
figure (, Fig. 8) that that 
part of the spherosome 
which contains the junc- 
tion of the two lateral am- 
bulacra (Figs. 9, n, 10), has a tendency to expand beyond the level 
of the mouth ; this is the first appearance of the lobes of the adult 
Bolina. This part of the spherosome increases rapidly in dimensions, 
and we have a minute Ctenophore with well-marked lobes, like a 
Bolina, and highly developed tentacles, like a Pleurobrachia (Fig. 11). 
Still greater changes are yet to take place ; we soon perceive that 

Fig. 2. Bolina in state of Fig. 1, seen from the broad side. 

Fig. 3. Somewhat younger than Fig. 1, seen from the abactinal pole. 

Fig. 4. Young Bolina, seen from the abactinal side, somewhat older than previous figures. 

Fig. 5. Formation of lateral tubes in young Bolina. 

Fig. 6. Bolina in which lobes begin to appear, seen from narrow side, same state as Fig. 4. 

Fig. 7. Somewhat more advanced than Fig. 6, the tube c' not yet having formed the circuit ; 
seen from the actinal side. 




BOLINA ALATA. 



17 



Fig. 8. 



Fig. 9. 




Fig. 10. 



Fig. 11. 



the long ambulacra do not remain regularly arched, but bend towards 
the vertical axis (Figs. 12, 
13) ; this bend is soon 
changed into a loop, which 
passes through a corre- 
sponding protuberance of 
the spherosome. This be- 
comes the auricle, from 
the angle of which (Fig. 
14) we also perceive a 
branch of the chjmiferous 
tube, which soon pushes 
its way through the gela- 
tinous mass, and forms a 

junction with the lateral tubes, exactly as we shall find it to be the 
case with Idyia. In the mean time the other ambulacra have been 

increasing in length, and we 
find that they reach almost to 
the lower end of the lobe ; 
when there, they make a sharp 
angle, turn upward, and form 
thus the beginning (Figs. 12, 
13) of the complicated system 
of windings which w r e find in 
the lobes of the adult Bolina. 
During the later stages of 
growth the tentacular appara- 
tus has been shifting its posi- 
tion, the opening coming nearer 
and nearer to the level of the mouth ; the tentacular bulb lengthening 
in proportion, and finally appearing like a long, narrow rod, with a 
slight swelling at the extremity, from, 
which the remnants of the threads 
of the tentacles are suspended. The 
only changes necessary to make this 
young an adult Bolina, are changes 

*/ o O 

of quantity. The apparent differ- 
ence in the mode of growth of the 

Fig. 8. The tentacular ambulacra have united, and the lobes () project well beyond the 
opening of the mouth. 

Fig. 9. About in the condition of Fig. 2, seen from the broad side. 
Fig. 10. Somewhat younger than Fig. 8, seen from the broad side. 
Fig. 11. Fig. 8, seen from the broad side. 

Fig. 12. Bolina with first appearance of the auricles, seen from the broad side. 
Fig. 13. Bolina of stage of Fig. 12, seen from the narrow side, 
xo. ir. 3 




Fig. 12. 



Fig. 13. 




18 



BOLINA ALATA. 



Fi S . H. 



lateral and longitudinal tubes is entirely done away with in subsequent 

changes, as we find that the 
short ambulacra are the lateral 
ambulacra, though at first they 
are more rapid in their growth, 
but are afterwards outstripped 
by the rapid increase in length 
of the longitudinal tubes ; but 
it must be remembered that, 
in this genus, the flattening of 
the spherosome takes place in 
different planes from Idyia and Pleurobrachia. The young Bolina has 
now attained a condition in which it will be very easy to recognize 
the different parts of the adult, if compared in homologous positions. 
Fig. 15 is an adult seen from the broad side, corresponding to Fig. 12 ; 
Fig. 1C is an adult seen from the narrow side, corresponding to Fig. 




Fig. 17. 




IL 





Z. Ill 



h 'r o 



13 ; Fig. 17 is an adult Bolina, seen from the actinal side, corre- 
sponding to Fig. 14 ; and in Fig. 18 we have the adult seen from the 
abactinal pole. 

Coast of New England, and northward to the Bay of Fundy ( Agassiz). 

Museum diagrams Nos. 1, 2, after L. Agassiz. 

Fig. 14. Fig. 13 seen from the actinal pole, and more magnified, r, circular tube ; in, auri- 
cles. 

Fig. 15. Adult Bolina seen from the broad side, ,/, longitudinal ambulacra; g, It, lateral 
ambulacra; o, eye-speck ; i-m, digestive cavity; i-o, funnel; v, lateral tube leading to tentacular 
apparatus just on level of mouth, in ; r, r, auricles ; t, t, prolongation of the longitudinal ambulacra ; 
n, H, same tubes turning upwards, bending down at x, x ; 2, s, point of junction of tubes from oppo- 
site sides ; -, prolongation of tubes from the lateral ambulacra. About half natural size. 

Fig. 1C. Fig. 15 seen from the narrow side, a, b, longitudinal ambulacra; c, /, lateral ambu- 
lacra ; other letters, as in Fig. 15. 

Fig. 17. Bolina seen from the actinal pole ; lettering as above. 

Fig. 18. Bolina seen from the abactinal pole, a, b, e, /, longitudinal ambulacra; c,fl,g,h, 
lateral ambulacra ; s, s, circumscribed area ; other letters, as above. 



MNEMIOPSIS. 



19 



Bolina vitrea AGASS. 

Bolina vitrea AGASS. Contrib. Nat. Hist. IT. S., Vol. III. pp. 269, 289, Fig. 93. 1860. 
? Bolina littoralis McCR. On the Development of two Species of Ctenophorse, 1857 ; Proc. Elliot 
Soc. N. 11.,-p. 1. 1858. 



The Bolina littoralis McCr. is probably either this 
species, or one of our species of Mnemiopsis ; but 
not having the means to determine this point, a 
figure (Fig. 19) of the Bolina vitrea Agass. is added 
here, to serve as a basis for its identification here- 
after. 

Reef of Florida (Agassiz) ; Charleston (McCrady). 



Fig. 19. 




Bolina microptera A. AGASS. 

Bolina septentrionalis AGASS. (non Mortens). Cont. Nat. Hist. U. S., HI. p. 289. 1860. 

The discovery of several species of Bolinidse on the eastern coast of 
North America, belonging to different genera, which had all been con- 
founded together, has induced me to examine anew the descriptions 
and drawings of the species of Bolina observed on the northwest coast. 
I have become satisfied that the species of Bolina here noticed is not 
the B. septentrionalis of Mertens, but differs specifically from it. It 
is quite elongated ; the lateral lobes are very short, with complicated 
windings of the long ambulacral tubes. This species resembles in out- 
line more the Bolina vitrea Agass. than any other. It has, like it, 
a long digestive cavity, but differs from it in the proportions of the 
lateral lobes, and the complexity of the windings of the long ambulacra. 
It is, like the B. vitrea, perfectly transparent and nearly colorless, of a 
slight bluish tinge ; the polar diameter measures about two inches. 
Found in June, in the Straits of Rosario, Washington Territory. 

Gulf of Georgia, W. T. (A. Agassiz). 



MNEMIOPSIS AGASS. 

Mnemiopsis AGASS. Cont. Nat. Hist. U. S., III. pp. 269, 290. 1860. 

The genus Mnemiopsis is remarkable among the Bolinidoe for the 
peculiar structure of the tentacular apparatus, which sends a branch 
along a deep furrow, protected by a lappet, to the base of the auricles. 

Fig. 19. Bolina vitrea seen from the broad side. Z 2 , F, long ambulacra; ?', / 8 , short ambu- 
lacra ; /, funnel ; d, digestive cavity ; I, tentacular tube ; x ^ X*' auricles ; /, /, anterior and poste- 
rior lobes ; /*', tentacle. 



20 



MNEMIOPSIS LEIDYL 



Mnemiopsis Garden! AGASS. 

Mnemiopsis Gardeni AGASS. Cont. Nat. Hist. U. S., III. pp. 269, 290, Figs. 95, 96. 1860. 



Fig. 20. 



The accompanying figures (Figs. 20, 21) of 
Mnemiopsis Gardeni Agass. are here introduced 
to show how striking are the differences in the 
proportions of the two Medusae of this genus 
found upon our coast. The great length of the 
digestive cavity, together with the size of the 
auricles and lobes, enable us at once to distin- 
guish this species from its ally, the Mnemiopsis 
Leidyi A. Agass. The genus Mnemiopsis had 
been placed by Professor Agassiz among the 
Mnemiidae, on account of the deep furrow sepa- 
rating the anterior and posterior lobes from the 
lateral spheromeres. The differences of form 
based upon this structural feature, which are in 
such striking contrast in Bolina and Mnemiopsis Gardeni, are for from 
being marked when we compare Bolina alata and Mnemiopsis Leidyi. 
Charleston, S. C. (L. Agassiz). 




Mnemiopsis Leidyi A. AGASS. 

This Medusa would readily be mistaken for a true Bolina, at first 
glance ; a closer examination, however, will show that, notwithstanding 
the short digestive cavity which reminds us of Bolina, we have the 
deep furrow separating the anterior and posterior lobes from the lateral 
spheromeres. The long ambulacra are covered with locomotive flap- 
pers to the actinal margin, and we have long auricles, showing that 
this is a Mnemiopsis, with longer anterior and posterior lobes than we 
have in the M)iemio2)sis Gardeni Agass. 

This species grows very large, specimens measuring six and even 
eight inches in length are frequently found. Like the other Cteno- 
phora3 of our coast, it is gregarious ; thousands being collected to- 
gether basking in the sun. It is exceedingly phosphorescent ; and 
when passing through shoals of these Medusa?, varying in size from 
a pin's head to several inches in length, the whole water becomes 
so brilliantly luminous that an oar dipped in the water up to the 

Fig. 20. Mnemiopsis Gardeni seen from the broad side, a, folds of digestive cavity. Letter- 
ing of Figs. 20 and 21 same as Fig. 19. 

Fig. 21. Fig. 20 seen from the actinal pole, o, mouth ; Z 4 , Z 5 > lateral ambulacra ; /> X"i auri ' 
cles ; Z 2 , Z 3 , Z 6 , Z 7 , anterior and posterior ambulacra. 



MXEMIOPSIS LEIDYI. 



21 



handle can plainly be seen, on dark nights, by the light produced 
by this illumination. The seat of the phosphorescence is confined to 
the rows of locomotive flappers, and so exceedingly sensitive are they 
that the slightest shock to the jar in which these Medusas are kept 
is sufficient to make them plainly visible by the light emitted from 
the eight phosphorescent ambulacra. This species is long, almost ellip- 
soidal, when at rest. (Fig. 22.) The auricles extend about one third 
their length beyond the oral aperture (o, Fig. 22), taking their origin 
on a level with the eye-speck (, Fig. 22). The prolongation of the 
chymiferous tubes, and their manner of anastomosing, is exceedingly 
simple ; we find nothing of the complicated bends and turns (Fig. 23) 



Fig. 22. 



Fig. 23. 





of the same tubes which we have in Bolma alata (Fig. 16). Bolina 
alata ranks among the most perishable of all our Medusae ; but this 
species seems to be very hardy, as I kept one large specimen alive 
for three weeks, during the whole of my stay at Naushon. This speci- 
men also laid eggs, which were developed into small Mnemiopsidas, 
after passing through stages in which it was almost impossible to say 
whether the Medusa w r as a young Pleurobrachia or not. As is the 
case in Bolina, the long tentacles, the globular outline of the young, 
resembled so closely the young of Pleurobrachia, which were develop- 
ing at the same time in another bottle, that frequently I would be 
unable, after leaving them for some time, to decide at once to which 

Fig. 22. Mnemiopsis Leidyi seen from the broad side, o, starting-point of branch of tentacu- 
lar apparatus extending along the furrow, f, to a, the base of the auricles. 
Fig. 23. The same as Fig. 22, seen from the narrow side. 



22 



MNEMIOPSIS LEIDYI. 



species the young belonged, as the difference between the diameters is 
far less marked than in Bolina. As they advance in size, the lobes 
become developed, the tentacles disappear, and they can be readily 
distinguished. The development goes on in the envelope for a week 
or ten days after the eggs are laid, the young Medusa not breaking 
through the outer membrane before it is well advanced, and capable 
of guiding its motions through the w r ater. The difference between the 
two transverse diameters of the spherosome is not as great as in Bolina, 
as will readily be seen by comparing the broad and narrow views of 
this Ctenophore (Figs. 22, 23). What is very peculiar in the genus 
Mnemiopsis is the peculiar development of the tentacular apparatus. 
It is not, as in Bolina, reduced to a simple bulb, with a few tentacles 
clustered at the base ; but is more like what we find in Lesueuria, 
where the threads of the tentacular bulb are quite long, and have a 
decided tendency to spread fan-shaped on both sides of the bulb. We 

have a rather small tentacular bulb placed 
at the end of a long, slender tube, a short 
distance above the opening of the actino- 
stome (o, Fig. 22). This tentacular bulb 
is protected by a kind of two-lapped hood 
(Fig. 24), the folds of which extend on 
each side along a groove towards the abac- 
tinal pole, to the very origin of the auri- 
cles, at ft, Fig. 22, taking their origin at 
o, Fig. 22 ; their origin from the bulb is 

better seen in Fig. 24, where a portion of the two branches of the 
tentacular apparatus, extending along this groove, is represented. 
It is exactly as if we had the tentacles of a Pleurobrachia, instead of 
swimming and floating freely about, protected by a kind of cover, and 
thus pressed towards the spherosome, and prevented from moving 
freely about. The whole spherosome is covered with minute spots, 
clusters of lasso cells scattered irregularly over the surface. (See 
Fig. 23.) 

From what we know of the amount of water which enters into the 
composition of Acalephs, and when we remember that not more than one 
half of one per cent, is animal matter, it seems strange that anything 
like a parasite should be found upon these Acalephs, and stranger still 
that this parasite should be able to find enough to live upon in such 
a delicate animal. As early as 1835 Sars had observed a species of 
intestinal worm (Scolex acalepharum) upon a large species of Mnemia 
(M. norvegica Sars), ten and even twelve specimens being found at- 

Fig. 24. A part of the tentacular apparatus, near the opening of the actinostome, to show the 
mode in which the branches of the tentacle extend, under cover of a lappet, towards the abactinal 
extremity. 




LESUEURIA. 23 

tached to the inner wall, near the upper part of the farrow, separating 
the lobes from the spherosome. Foster, in 1841, found a species of 
Filaria, which he called Tetrastoma Playfair'd, upon a species of Cy- 
dippe y Greene and others have also seen parasites upon Hydroid 
Medusas ; and finally, in this species, five to eight worms, which re- 
semble more a leech than anything else, though I cannot refer them 
to any of the genera which are described, attaining a length of an 
inch, and even an inch and a half, are frequently found attached to 
the inner wall, in the upper part of the long furrow, near the eye- 
speck. Hardly a specimen of this Medusa is found which has not one 
or two of these parasites. It is a long, flesh-colored, cylindrical worm, 
with five longitudinal white lines extending the whole length ; the 
mouth, by which it is fastened to the jelly-fish, occupying the whole 
of the anterior part. This mouth can be closed, extended to a point, 
snd, when inserted in the substance of the jelly-fish, it is expanded 
again like the mouth of a trumpet, and the worm is firmly fastened. 
These worms are sluggish in their movements, and when detached and 
disturbed hardly show signs of life by the slow contractions of their 
body. The worms live several days after they have been separated 
from the Medusae. 

Naushon, Buzzard's Bay (A. Agassiz). 



LESUEURIA MILNE EDW. 

Lesueuria MILNE EDW. Ann. Sc. Nat., XVI, 1841, p. 199. 

Lesueuria LESS. Zooph. Acal., p. 90. 1843. 

Lesueuria AGASS. ' Cont. Nat. Hist. U. S., III. p. 290. 1860. 



Lesueuria hyboptera A. AGASS. 

In Lesueuria the tentacular ambulacra are by far the most developed ; 
the locomotive flappers of the short ambulacra extend but to the be- 
ginning of the auricle ; the immense size of this apparatus, projecting 
beyond the level of the mouth, and the winding of the tube running 
through the auricle, before it joins the lateral chymiferous tube, gives 
this tube a great length when compared to the longitudinal ambulacra, 
which run in an almost straight course from the abactinal pole till they 
meet the horizontal part of the tentacular branch which connects near 
the mouth with the opposite tentacular apparatus. The tentacular ap- 
paratus is similar to that of Bolina, and is also situated in the short 
transverse axis. The lobes of a Lesueuria can hardly be called by that 
name, as what corresponds to the lobes of Bolina are small projections 
scarcely reaching below the level of the mouth, and in which all we 



24 



LESUEURIA. 



find corresponding to the complicated windings of the longitudinal 
ambulacra are a few short, straight projections of the ambulacral tubes, 
running like spurs into the thickness of the spherosome. 

The outline of our Lesueuria (Fig. 25) is entirely different from that 
of the Mediterranean ; the latter is quite ellipsoidal, while the North 
American species shows a strong tendency to bulging out near the 
actinostome, and to imitate in its outline that of Bolina, mutilated 
specimens of which, when seen swimming in the water, can easily be 
mistaken for this species. It is only on noticing the position of the 
mouth, the great length of the auricles, that the mistake becomes 
apparent. Lesueuria is as transparent as Bolina, and even more slug- 
gish ; it grows to a large size, four inches in polar diameter, and is 
exceedingly abundant during September, large numbers being visible 
on almost any clear, hot day. Its phosphorescence is a very peculiar 
bluish light, of an exceedingly pale steel color, but very intense. 

What is peculiar to our species is the almost rectangular outline 
which it has when seen from the broad side (Fig. 25). The shortness 



Fig. 25. 




Fig. 26. 




of the funnel ; the extreme tenuity of the chymiferous tubes ; the deep 
depression, or rather cut, in which the eye-speck is situated, for the 
abactinal part of the gelatinous spheromeres joins so closely above this 
that the eye-speck literally seems imbedded in the solidity of the 



Fig. 25. Lesueuria seen from the broad side, natural size. 
Fig. 26. Fig. 25 seen from the narrow side. 



OCYROE.E. 



25 



Fig. 27. 




Fig. 28. 



spherosome. The lateral tubes are also very attenuated, and bulge 
well out from the digestive cavity, as is 
seen in a profile view from the narrow 
side (Fig. 26). The view from the narrow 
side shows this species to be compressed 
to a far greater extent than anything we 
know in Bolina ; approaching almost to 
Mertensia. When in motion the auricles 
are often held out extended from the body 
(Fig. 26), one pair bending one way, and 
the other in the opposite direction, as is 
shown in Fig. 27 ; the outline of the body 
when seen from the abactinal pole is nearly 
elliptical (Fig. 27), and we have not the 
strongly-ribbed appearance so characteris- 
tic of the other Ctenophorae. The connec- 
tion between the lateral and longitudinal 
ambulacra, forming a circular tube round 
the actinostome, can be traced in Fig. 28, 
and it differs in no essential way in its 
mode of formation from what we observe 
in Bolina. 

Massachusetts Bay, and Newport, R I. (A. Agassiz). 

Museum diagram No. 2 after A. Agassiz. 




Family OCYROE^ Less. 

Ocyroece LESS. Zooph. Acal., p. 98. 1813. 

Ocyroece AGASS. Cont. Nat. Hist. U. S., III. p. 292. 1860. 



OCYROE RANG. 

Ocyroe RANG (nan Per. et Les.). Mem. dc la Soc. d'Hist. Nat., IV. p. 170. 1829. 

Oci/roe LESS. Zooph. Acal., p. 98. 1843. 

Ocyroe AGASS. Cont. Nat. Hist. U. S., III. p. 292. 1860. 



Ocyroe maculata RANG. 

Ocyroe maculata RANG. Me'm. Soc. d'Hist. Nat. de Paris, IV. 1829, PI. 20, Fig. 1. 

Ocyroe maculata LESS. Zooph. Acal., p. 99. 1843. 

Ocyroe maculata AGASS. Cont. Nat. Hist. U. S., III. p. 292. 1860. 

Antilles (Rang). 

Fig. 27. Lesueuria seen from the abactinal pole. 

Fig. 28. Seen from the actinal pole, to show the connection of the lateral and longitudinal 
ambulacra. 

NO. II. 4 



26 SACCATE. 



SUBORDER SACCAT^E AGASSIZ. 

Saccatce AGASS. Cont. Nat. Hist. U. S., III. p. 293. I860. 
Callianiridce ESCH. Syst. der Acal., p. 21. 1829. 



Family MERTENSID^E Agass. 

Mertensidcz AGASS. Cont. Nat. Hist. U. S., III. pp. 196, 293. 1860. 

MERTENSIA LESS. 

Mertensia LESS, (non Gegenb.). Zooph. Acal., p. 100. 1843. 

Mertensia ovum MORCH. 

Ci/flippe (M< rtfnxia) orum MORCII. In Nat. Bid. til en Besk. af Grdnland, p. 97. 1857. 

Beroe ovum FAB. Faun. Groenl. 1 780. No. 355. 

Beroe cuculhis MOD. Svensk. Vet. Ak. Nya Handl., XL 1 790. 

Beroe pilaus SCOR. (nee Fab. nee Mull.). Arct. Reg., II. PI. XVI. Fig. 4. 1820. 

Cydippe ovum ESCH. Syst. d. Acal., p. 25. 1829. 

('//if/pjic cuculhis ESCH. Syst. d. Acal., p. 25. 1829. 

Mertensia Scorexlyi LESS. Zooph. Acal., p. 100. 1843. 

Cydippe cucumit LESS. (syn. not correct). Zooph. Acal., p. 105. 1843. 

Mertensia cucullus AGASS. Cont. Nat. Hist. U. S., III. p. 293. 1860. 

The compression of Mertensia coincides with that of Pleurobrachia. 
The axis passing through the tentacular apparatus is more than twice 
as long as the coeliac diameter. What is very characteristic of this 
genus is the great distance at which the lateral chymiferous tubes are 
placed from the digestive cavity, and the close connection which is 
shown there to exist between the tentacular apparatus and the lateral 
tubes, the base of the tentacular apparatus seeming to give rise to 
this long, slender tube, enclosing the digestive cavity in its two wide 
arches, when seen from the broad side. (Fig. 29.) The spherosome 
rises so much above the opening for the passage of the tentacular appa- 
ratus, that it seems, in adult specimens, as if the tentacular ambulacra 
were the longest. 

Only one large adult specimen of this jelly-fish has been taken in 
our Bay. It was at first mistaken for a large Pleurobrachia ; but the 
great flattening of the spherosome, and the peculiar spiral motion 
which they keep up while active, soon enables one to distinguish them 
readily from that genus, while swimming in the water. The color, also, 
is of a light-pink hue ; the spermaries are of a very brilliant crimson, 
the ovaries being more dull. It has the rosette of an Idyia, with the 



MERTENSIA OVUM. 



27 



Fis 29. 



edges smooth ; the circumscribed area is quite small ; the tentacles are 
but moderately long, apparently not capable of as 
great expansion as Pleurobrachia. Our species of 
Mertensia is exceedingly delicate ; the specimens 
taken at Nahant and Eastport, though treated 
with the greatest care, not living more than a 
couple of hours when brought into confinement. 
I suppose this to be the Beroe ovum of Fabricius. 
The difference between the tentacular chy- 
niiferous tubes and the median pairs is very 
marked in young specimens. In the youngest 
Mertensia observed, we find the same pear-shaped 
form noticed in young Pleurobrachia. (See Fig. 41.) 
The ambulacra, however, are far more advanced 
in comparison to the tentacles, and occupy nearly 
the whole of the spherosome (Fig. 30) ; the 
pouches of the ambulacra concealing almost en- 
tirely the digestive cavity. There are also very 
prominent orange pigment-cells, which are not 
found in the young of Pleurobrachia, along the 

rows of locomotive flappers ; the tentacles remain simple much longer 
than in Pleurobrachia. The young Mertensia is not as much com- 
pressed as the young Pleurobrachia (compare Figs. 31 and 46, repre- 
senting almost corresponding stages of Mertensia and of Pleurobrachia). 




Fig. 30. 



Fig. 31. 





The compression goes on increasing with age, and in the adult it has 
become one of the striking characteristics of the genus. With advan- 
cing age the actinal part of the young Medusa becomes more promi- 
nent, while the ambulacra have remained nearly unchanged, the long 
and short ambulacra not retaining quite the same proportions they had 
before they were almost equally developed ; the funnel has become 



Fi"-. 29. Adult Mertensia seeii from the broad side. 

Fig. 30. Young Mertensia seen from the broad side, with a simple tentacle. 

Fi<>-. 31. The same as Fig. 30, seen from the abactinal pole. 



28 



MERTENSIA OVUM. 



Fig. 32. 




Fig. 33. 





formed, the digestive cavity (d) and the lateral tubes (?) are well de- 
fined. (Fig. 32.) In a view from below of this same individual (Fig. 33) 
we notice the narrowing of the large ambulacral pouch into somewhat 

more circumscribed 
tubes. In the next 
stage which is here 
represented ( Fig. 34), 
the ambulacra have 
assumed still more 
the aspect of tubes, 
the funnel has elon- 
gated, the tentacles 
have begun to send 
out lateral processes, 
the lateral tubes ex- 
tend nearly to the 
level of the mouth, 

the actinal part of the young Medusa having 
taken a still greater development, and having 
become as long as the ambulacral part. The 
tubes, both ambulacral and lateral, when seen 
from below (Fig. 35), are also more narrowed 
and better circumscribed. In the next stage the development of the acti- 
nal part of the spherosome (Figs. 36, 37) has become so striking, that we 

cannot fail to recognize in the young Acaleph a 
Mertensia. The difference between the coeliac and 
diacoeliac axis is quite prominent, giving to the 
animal, when viewed from the broad (Fig. 36) or 
narrow side (Fig. 37), a totally different aspect. 
The tentacular apparatus differs from that of Pleu- 
robrachia in being limited to the abactinal part of 
the spherosome, and not extending towards the 
actinostome, as in Pleurobrachia. In the young 
stages the lateral tubes are still quite close to the 
digestive cavity, and do not yet flare out, as in the 
adult. (See Figs. 29, 36.) The ambulacra are very nearly equally 
developed, the tentacular pairs and the median tubes differing but 
slightly in length. The tentacles are lashed and covered with large 
orange pigmen1>spots, similar to those of the rows of locomotive 

Fig. 32. Somewhat more advanced Mertensia, seen from the narrow side ; the lateral tubes, I, 
are present. 

Fig-. 33. The same as Fig. 32, seen from the actinal pole. 

Fig. 34. Still more advanced Mertensia, seen from the narrow side. 

Fig. 35. The same as Fig. 34, seen from the actinal pole ; the tubes are circumscribed, and 
the tentacular apparatus isolated. 



Fig. 35. 




CYDIPPIDJE. 



29 



flappers. The pigment-spots become smaller and less conspicuous with 

Fig. 36. Fig. 37. 



advancing age. 





This species is exceedingly common in Eastport harbor, during the 
month of September. 

Arctic Ocean (Mertens, Scoresby) ; Baffin's Bay (Fabricius) ; Massa- 
chusetts Bay, and Eastport, Me. (A. Agassiz). 



Museum diagram No. 3 after Alex. Agassiz. 



Family CYDIPPID^E Gegenb. (rest AG.) 

CydippidcE GEGENB. Archiv f. Nat., 1856, I. p. 196. 
Callianiridce ESCH. (p. />.) ' Syst. d. Acal., p. 21. 1829. 
Cydippidce AGASS. Cont. Nat. Hist. U. S., in. p. 293. 1860. 



PLEUROBRACHIA FLEM. 

Pleurobracliia FLEM. Phil. Zool., II. p. 612. 
Cydippe ESCH. Syst. tier Acal., p. 29. 1829. 
Cydippe LESS. Zooph. Acal., p. 104. 1843. 
Pleurobracliia AGASS. Mem. Am. Acad., IV. 1849, p. 314. 
Pleurobracliia AGASS. Cont. Nat. Hist. U. S., HI. p. 203. 1860. 

Fig. 36. Still further advanced Mertensia, seen from the broad side. 

Fig. 37. Young Mertensia about in the same condition as that of the preceding figure, seen 
from the narrow side. The main branches of the ainbulacral system have lost the character of 
pouches. 



30 



PLEUROBRACHIA RHODODACTYLA. 



Pleurobrachia rhododactyla AGASS. 

Pleurobrachia rhododactyla AGASS. Mem. Am. Acad., IV. p. 314, Pis. 1, 2, 3, 4, 5. 

Pleurobrachia rhododactyla AGASS. Cont. Nat. Hist. U. S., III. pp. 203, 294, PL 2\ 18GO. 

Beroe pileus FAB. (non Flem., Miill., and Eseh.). Faun. Grb'nl. 1780. No. 354. 

C yd ippe pileus GOULD. Rep. Inv. Mass., p. 349. 1841. 

Pleurobrachia rhododactyla STIMPS. Mar. Inv. Grand Manan, p. 11. 1853. 

C ydippe pileus MORCH. In Naturhist. Bid. til en Besk. af Gronland, p. 97. 1857. 

Pleurobrachia Scoresbyi MORCII. In Naturh. Bid. til en Besk. af Gronland, p. 98. 1857. 

Pleurobrachia rhododactyla PACKARD. List of Animals dredged near Caribou Island. 18G3. 

The young Pleurobrachia early assumes an outline resembling the 
adult ; it is slightly pear-shaped, with two very small protuberances, 
like buttons, indicating the first appearance of the tentacles (Figs. 
38-40, ), and has a very large transparent sphere (e) with two or 



Fig. 38. 



Fig. 39. 




Fig. 40. 





three granules, as an eye-speck. The first cavity formed in this em- 
bryo is a small spherical space (Figs. 38-40, d) near the pole opposite 
the eye-speck. As this grows larger it becomes elliptical, reaching to 



Fig. 41. 



Fig. 43. 



Fig. 42. 





the base of the tentacular (Fig. 41, f) knob, which now extends, like 
the handle of a jar, beyond the outline ; this cavity is the digestive 
cavity, and there is up to this time no sign of ambulacra! tubes or cavi- 

Fig. 38. Young Pleurobrachia seen from the broad side. 

Fig. 39. Same as Fig. 38, seen from the narrow side. 

Fig. 40. Same as Fig. 38, seen from below. 

Fig. 41. Pleurobrachia somewhat more advanced, seen from the broad side. 

Fig. 42. Same as Fig. 43, seen from above. 

Fig. 43. Same as Fig. 42, seen from the broad side, older than Fig. 41. 



PLEUROBRACHIA RHODODACTYLA. 



31 



Fig. 44. 




ties of any kind. The position of the ambulacra! system is early well 
defined by four short double rows of combs, each row not having more 
than three or four combs (Figs. 38-41). The spherosome early shows 
the great difference in the size of the longitudinal and coeliac diameters, 
the tentacular diameter being nearly twice as long as the other (Figs. 
40, 42). The locomotive rows extend rapidly to the level of the upper 
part of the digestive cavity. At this time the ambulacral cavity makes 
its appearance as a small spherical cavity, in the same way as the diges- 
tive cavity. The ambulacral cavity increases rap- 
idly, soon attains the size of the digestive cavity, 
and occupies the w T hole of the abactinal extrem- 
ity of the animal (Fig. 43, o). At this time the 
young Pleurobrachia is quite pear-shaped, with 
solid tentacles about as long as the polar diam- 
eter. The ocular sphere is large, very promi- 
nent (Fig. 43, e}. There are two large elliptical 
cavities, of nearly equal size (Fig. 43, o, d}. In 
the next stage the two cavities differ in their 
outline, the ambulacral cavity becoming more 
and more rectangular, and the digestive cavity 
triangular, the two being separated by a wall which grows thinner and 
thinner. The combs of the ambulacral rows increase in size, and the 
flappers are quite long, equalling in length half the transverse diameter 
of the spherosome. The ambulacral cavity extends towards the abac- 
tinal region on both sides of the thickening of the wall, supporting the 
sensitive bulb. This is the first sign of the for- 
mation of the funnel (Fig. 44,/), and its division 
into the two branches, opening outwards. The 
compression of the digestive cavity is plainly 
seen at this stage, as when seen facing the ten- 
tacles the cavity comes close to the outer wall 
(Fig. 44), while when seen at right angles to 
the tentacular diameter it occupies but a much 
smaller space (Fig. 45). The tentacular bulb becomes more isolated, 
the tentacle is about three times as long as the polar diameter. During 
all this time, and from the first appearance of the locomotive flappers, 
the young Medusa moves about with the greatest rapidity, turning over 
in every possible direction, running round and round, with the diges- 
tive cavity forward, in the envelope of the egg, as if trying to make 
its escape from it ; while at other times the young Medusa remains 

Fig. 44. Pleurobrachia in which the digestive cavity and the ambulacral cavity are already- 
connected, immediately before the escape of the Medusa from the egg. 

Fig. 45. Same as Fig. 44, somewhat less magnified, to show the relative size of egg envelope 
and embrvo. 



Fig. 45. 




32 



PLEUROBRACHIA RHODODACTYLA. 



Fig. 46. 




Fig. 47. 



poised in the centre of the egg, rotating slowly on its axis, imitating, 
while still in the egg, all the movements which are so characteristic of 
the adult. The young Medusa, before it escapes from the egg, occupies 
a comparatively small space, having thus ample room for its manifold 
movements. In Fig. 44 the outline of a part of the egg is seen ; Fig. 45 
is the same as Fig. 44 from the opposite side, showing the whole egg. 

Before the young leaves the egg, we 
find that the ambulacral cavity and 
digestive cavity connect by means of 
a small opening in the centre of the 
dividing wall, and at the same time a 
depression at the actinal pole soon 
increases sufficiently to pierce through 
the wall, and make an opening, 
the mouth (Fig. 46). The young 
Pleurobrachia now makes its escape 
from the egg, and the changes it undergoes are very rapid ; the funnel 
becomes well isolated, and the digestive cavity quite compressed, and 
we see the first sign of the separation of the double row of locomotive 
flappers into two very distinct rows. At the same time, when facing 

the tentacular bulb, we see a small triangular 
pouch extending along the digestive cavity, 
which, when seen in profile, plainly appears 
to be nothing but a coecum of the ambulacral 
cavity, formed exactly as in Bolina (Fig. 5). 
These pouches are the rudimentary lateral 
chymiferous tubes so characteristic of Cteno- 
phorae. At this stage the ambulacral flappers 
are not as near the abactinal pole as in 
former stages, on account of the elongation 
of portions of the spherosome. The lateral 
tubes increase rapidly in length, and soon 
extend to the level of the mouth (Fig. 47, ), 
while the forking of the ambulacral tubes becomes more deep. We 
notice also at this time a marked difference in the size of the ambu- 
lacral tubes. The tentacular ambulacra (those on each side of the 
tentacular apparatus) are much shorter than the longitudinal ambulacra 
(Fig. 48, c). The tentacle, also, is no longer a simple solid thread ; 
long, slender offshoots, similar to the tentacle, have developed near the 

Fig. 46. Same as Fig. 44, seen from actinal side. 

In all the preceding figures the embryo has been drawn without the egg envelope ; but it must 
be remembered that the little Medusa does not escape from the egg till it reaches the condition of 
Fig. 44. 

Fig. 47. Pleurobrachia swimming freely about, in which the lateral tubes, the funnel, have 
become highly developed ; seen from the broad side. 




PLEUROBRACHIA RHODODACTYLA. 



33 



point of attachment., and the peculiar abactinal system (Fig. 48) has 
also made its appearance. The young Pleurobrachia has now all the 



Fig. 48. 



Fig. 49. 





Fig. 50. 





appearance of the adult, only it is more pear-shaped, and it is about one 
half of an inch in polar diameter. The ambulacra are yellowish, with large 
orange pigment-cells on the surface of the ambulacra! tubes (Fig. 49). 

The difference between the 
axes, the coeliac and the clia- 
coeliac, grows less and less with 
advancing age, till they assume 
the almost identical outlines of 
the adult, as seen in Fig. 50, 
which represents the coeliac 
and diacoeliac views of an adult. 
In Figs. 47 and 48 we have 
also the first trace of the cirri 
which assume such graceful 
shape in the tentacles of the 
adult Medusa (Fig. 51) ; the 
cirri begin nearest the tentac- 
ular bulb, and there are at 
first but two or three at the base of each tentacle. 

Greenland (Fabricius) ; New England (Agassiz). 

Cat. No. 366, Nova Scotia, Anticosti Expedition, 1861. 

Museum diagrams Nos. 4, 5, after L. Agassiz and Alex. Agassiz. 

Fig. 48. Somewhat less advanced than Fig. 47, showing the lateral tubes from the narrow 
side, as a prolongation of the ambulacral cavity. 

Fig. 49. Pleurobrachia about in condition of Fig. 47, seen from actinal pole. 
Fig. 50. Adult Pleurobrachia, from the head and narrow side, natural size. 
Fig. 51. Adult Pleurobrachia in a natural attitude, natural size. 

5 




& 

NO. n. 



34 DRYODORA. 

Pleurobrachia Bachei A. AGASS. 

Pleurobrachia Bachei A. AGASS. ; in Agassiz's Cont. Nat. Hist. U. S., III. p. 294. 1860. 

Pleurobrachia Bachei A. Agass. resembles Pleurobrachia rhododac- 
tyla in its general appearance, having about the same size ; the color 
of the spherosome and of the tentacles being nearly the same. The 
opening of the tentacular sac, however, is at a greater distance from 
the pole, and the tentacles come out more from the side of the sphero- 
some than in Pleurobrachia rhododactyla. The cceliac cavity is also 
shorter, the funnel is longer, and the actinal portion of the sac shorter. 
The branches leading from the digestive cavity to the chymiferous 
tubes are much longer and more slender, the junction being above the 
opening of the tentacular sac, while in Pleurobrachia rhododactyla 
it is below, nearer the actinal pole. The greatest swelling of the 
spherosome is nearer the actinal pole, not in the middle of the actinal 
axis. 

Found in the Gulf of Georgia, and entrance of Admiralty Inlet, W. T., 
during the whole Summer of 1859, from May to September. 

Washington Territory (A. Agassiz). 

Cat. No. 288, Gulf of Georgia, W. T., 1859, A. Agassiz. 



JANIRA OKEN. 

Janira OKEN. Lehrb. d. Naturg., III. 1815. 

Janira cucumis LESS. 

Janira cucumis LESS. Zooph. Acal., p. 104. 1843. 

Beroe cucumis MERT. (non Fab. n. Esdi.). Mem. Ac. St. Pet,, p. 522, PI. VHI. 1843. 

Janira cucumis AGASS. Cont. Nat. Hist. U. S., HI. p. 294. 1860. 

Between Sitka and Unalaschka (Mertens). 



DRYODORA AGASS. 

Dryodora AGASS. Cont. Nat. Hist. U. S., III. p. 196. 1860. 

EscJischoltzia LESS. (ex. p.). Zooph. Acal., p. 102. 1843. 

Mertensia GEGEXBAUR (jwn Less.). Archiv f. Nat., 1856. I. p. 198. ' 



Dryodora glandiformis AGASS. 

Dryodora glandiformis AGASS. Cont. Nat. Hist. U. S., HI. p. 294. 1860. 
Beroe glandiformis. MERT. Mem. Acad. St. Pet., p. 530, PL XL 1833. 
Eschscholtzia glandiformis LESS. Zoopb. Acal., p. 102. 1843. 
Mertensia glandiformis GEGEXB. Archiv f. Nat., 1856, I. p. 198. 

Behring's Strait (Mertens). 



EURYSTOM.E. 35 



SUBORDER EURYSTOM^E LEUCK. 

Etirystomce LEUCK. ; in Van d. Hoeven Handbnch d. Zool. German Transl. 1850. 
Eurystomce AGASS. Cont. Nat. Hist. U. S., III. p. 295. 1860. 



Family BEROID^E Esch. 

BeroidfK ESCH. Syst. d. Acal., p. 38. 1829. 

Beroidce AGASS. Cont. Nat. Hist. U. S., III. p. 295. 1860. 



BEROE BROWN. 

Beroe BROWN. Nat. Hist. Jam., p. 384. 1756. 
Medea ESCII. (ex p.}. Syst. d. Acal., p. 38. 1829. 
Cydalisia LESS. Zool. de la Coq., p. 101. 1829. 
Ci/dalisia LESS. Zooph. Acal., p. 138. 1843. 
Beroe AGASS. Cont. Nat. Hist. U. S., III. p. 295. 1860. 



Beroe punctata CHAM. & EYSEN. 

Beroe punctata CHAM. & EYS. Nov. Act., X. p. 361, PI. 31, Fig. 1. 

Beroe punctata ESCH. Syst. d. Acal., p. 37. 1829. 

Beroe punctata BLAINV. Man. d'Actin., PI. 7, Fig. 2. 1830. 

Cydalisia punctata LESS. Zooph. Acal., p. 139. 1843. 

Beroe punctata McCR. Proc. Elliot Soc. N. H., p. 1. 1858. 

Beroe punctata AGASS. Cont. Nat. Hist. U. S., III. p. 295. 1860. 

McCrady has identified a species of Beroe found at Charleston with 
the B. punctata Esch. I am inclined to think that it may prove to be 
one of the species of Idyopsis found on the coast of Florida. 

Charleston, S. C. (McCrady). 



IDYIA FREM. 

Idyia FREM. Nouv. Bull. Soc. Phil., 1809, p. 329. 
Medea ESCH. (ex. />.). Syst. d. Acal., p. 38. 1829. 
Idyia LESS. Zooph. Acal., p. 132. 1843. 
Idyia MERT. Mem. Acad. St. Petersb., II. p. 532. 1833. 
Idyia AGASS. Cont. Nat. Hist. U. S., III. p. 295. 1860. 



Idyia ovata LESS. 

Idyia ovata LESS. Zooph. Acal., p. 134. 1843. 

Beroe BROWN. Nat. Hist. Jam., p. 384. 1756. 

Medusa Beroe LINN: Syst. Nat. ed. X. p. 660. 

Beroe ot-ata ESCH. Syst, d. Acal., p. 36. 1S20. 

Idy'ui onita AGASS. Cont. Nat. Hist. U. S., III. p. 295. 1860. 

Is this not one of our species of Idyopsis ? 
Jamaica (Patrick Brown). 



3(3 IDYIA ROSEOLA. 



Idyia cucumis LESS. 

Idyia cucumis LESS. Zooph. Acal., p. 133. 1843. 
Beroe cucumis FAB. Fauna Gronl., 1780, No. 353. 
Beroe cucumis ESCH. Syst. d. Acal., p. 36. 1829. 
Medea fulgens LESS. Zooph. Acal., p. 136. 1843. 
Beroe cucumis MOKCH; in Naturh. Bid. af Gronland, p. 98. 1857. 
Idyia cucumis AGASS. Cont. Nat. Hist. U. S., III. p. 296. 1860. 
? Idyia borealis LESS. Zooph. Acal., p. 134. 1843. 

The many species of Idyia which are described from the arctic parts 
of the Atlantic Ocean, and which have been identified with Idyia 
cucumis and Idyia borealis Less, by Professor Agassiz, are probably 
all identical with the Beroe cucumis of Fabricius. 

Baffin's Bay (Fabricius). 



Idyia roseola AGASS. 

Uyia roseola AGASS. Cont, Nat. Hist. U. S., HI. pp. 270, 296, Pis. 1, 2. 1860. 
Idi/ia roseola PACK. List of Animals dredged near Caribou Island. 1863. 

In the youngest Idyia which I have had the opportunity to observe 
the digestive cavity, the eight ambulacral rows, the lateral chymiferous 
tubes were already developed. When seen from above, the ambulacral 
cavity has the shape of an eight-lobed rosette, with loops of different size. 



Fig. 52. 

Fig. 53. 






occupying half the space of the spherosome, seen in profile (Fig. 52), and 
the whole when seen from the abactinal pole (Fig. 53). We are struck 
by the immense size of the lateral tubes (I), and find that the inequality 
in the lobes of the ambulacral cavity is caused by the greater size of 

In Idyia, owing to a mistake in the lettering of the figures, c' is the long tube, and c the short 
ambulacra! tube, so that the lettering of Idyia does not exactly correspond to that of the other 
young Ctenophorse. 

Fig. 52. Young Idyia, seen from the narrow side. 

Fig. 53. Fig. 52, seen from abactinal pole. 

Fig. 54. Young Idyia, in which the ambulacral tubes are distinct, seen from the narrow side. 



IDYIA ROSEOLA. 



37 



the longitudinal ambulacra, the rows of locomotive flappers extending 
but little way from the abactinal pole, as is the case in Pleurobrachia. 
We find also the whole spherosome covered with large pigment cells. 



Fig. 56. 



Fig. 57. 




Fig. 55. 





Iii specimens slightly older, the difference in size between these two 
sets of tubes becomes more marked in proportion as they become sepa- 
rated and distinct, as is seen in the two figures, in profile (Fig. 56) and 



Fig. 60. 




Fig. 58. 





from above (Fig. 55). The manner in which the ambulacral tubes are 
formed, by the drawing up into loops of the original chymiferous cavity, 
is very easily followed in Idyia. It is the same in all the Ctenophorse 

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

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

Fig. 57. The chymiferous tubes, c', have extended to level of actinostome ; narrow side. 

Fig. 58. The chymiferous tubes, c', have united with the lateral tubes, and formed a circular 
tube, towards which the short ambulacra, c, are fast pushing their way. First trace of the ramifi- 
cations on the long tubes, c'. Figs. 58 -GO are seen from the broad side. 

Fig. 59. The short ambulacra, c, have nearly united with the circular tube ; the spurs of the 
ambulacra have become more numerous and quite prominent. 

Fig. GO. 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. 



38 



IDYIA CYATHINA. 



Fig. 61. 



Fig 62. 



I have observed ; but as the tubes of the other genera are so soon 
hidden by the rows of locomotive flappers, it becomes more difficult to 
follow this separation than in Idyia, where the ambulacra retain always 
a great size, and develop faster than the rows of flappers which cover 
them. The longitudinal ambulacra increase rapidly in length, pushing 
their way through the gelatinous mass (Fig. 56, c') till they reach the 
level of the mouth (Fig. 57) ; they then bend inwards (Fig. 58) till 
they meet the lateral chymiferous tube. The lateral ambulacra go 
through the same process (Figs. 58, 59) ; and thus we have formed, by 

the junction of the ambulacra 
with the lateral chymiferous 
tubes, a circular tube round the 
mouth. (Fig. 60.) The distinc- 
tion between the longitudinal 
and lateral ambulacra is always 
maintained by the length of the 
rows of locomotive flappers which 
cover the ambulacral tubes. The 
fringed abactinal apparatus is in 
the young a circular ring ; afterwards it has four folds developed at 
the extremity nearest the sensitive bulb (Figs. 59, 61), which soon 
become fringes similar to those of the adult. Shortly before the circuit 
is thus completed (Figs. 58, 59), the ambulacra of the young Idyia give 
out a few lateral processes, the first traces of the ramifications of the 
ambulacra of the adult (Fig. 62), which become more and more numer- 
ous until the processes branch as in Fig. 60. 

The short chymiferous tubes are, as in Pleurobrachia, on each side of 
the lateral tubes, while in Bolina this is not the case, the long tubes 
being near the short transverse axis. 

Coast of New England, and northward to Bay of Fundy (Agassiz). 
Catalogue No. 368, Nova Scotia, Anticosti Expedition, 1861. 
Museum diagrams Nos. 6, 7, after Alex. Agassiz and L. Agassiz. 




Idyia cyathina A. AGASS. 

Idyia cyathina A. AGASS. ; in Agassiz's Contrib. Nat. Hist. U. S., Vol. III. p. 296. I860. 

This species differs from the Idyia roseola Agass. of the coast of New 
England, by the sudden widening of the spherosome from the abactinal 
pole. It is widest at two thirds the distance from the mouth ; it then 
tapers as suddenly for another third of the distance to the mouth, and 

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

Fig. 62. Adult Idyia, reduced in size one half. , ami opening ; fi, lateral radiating tube ; 
c, circular tube ; d, e, /, </, /*, vertical rows of flappers. Seen from the broad side. 



IDYIOPSIS. 



39 



then very gradually. The actinal extremity of the spherosome is 
slender and exceedingly movable, and the edges of the actinostoine 
can be extended so that it presents the appearance of two distinct 
lobes. The ovaries and spermaries are much longer sacs than in /. 
roseola, and not so numerous. The locomotive flappers do not extend 
as far down the chymiferous tubes as they do in our species, though 
this difference may only be one of age. Found in the Gulf of Georgia, 
W. T., and in the eastern part of the Straits of Fuca, during the sum- 
mer of 1859. The habits of this Idyia are somewhat different from 
those of our species. Instead of the sluggish movements which charac- 
terize Idyia roseola, Idyia cyath'ma is very active, and seems to retain 
the embryonic features of the genus, short rows of flappers, and 
great activity in its adult condition. 

Northwest coast of North America (A. Agassiz). 

Cat. No. 287, Gulf of Georgia, W. T., A. Agassiz, 1859. 



IDYIOPSIS AGASS. 

Idyiopsis AGASS. Cont. Nat. Hist. U. S., III. pp. 288, 296. 1860. 

Short vertical axis ; ambulacra very prominent ; interambulacra con- 
cave ; fringes of circumscribed area arranged in two prolonged circles ; 
numerous branching tubes arising from circular tube ; compression of 
the body very striking. (Agassiz.) 



Idyiopsis Clarkii AGASS. 

Idyiopsis Clarkii AGASS. Cont. Nat. Hist. U. S., HI. pp. 288, 296, Figs. 101, 102. 



1860. 



Fig. 63. 



Fig. 64. 



r 



It remains yet to be shown 
whether the two species of Idyi- 
opsis here mentioned may not be 
identical with species of Idyia de- 
scribed by Eschscholtz as found on 
the Brazilian coast and in the Gulf 
of Mexico. The figures of Idyiop- 
sis given by Professor Agassiz are 
here reproduced. (Figs. 63, 64.) 

South Carolina (L. Agassiz). 



Fig. 63. Idyiopsis Clarkii seen from the broad side. /, funnel ; Z 2 , Z 7 , anterior and posterior 

ambulacra ; J 1 , / 8 , lateral ambulacra ; d, digestive cavity ; o, mouth ; r, the lateral tube. 

Fig. 64. Fig. 63, seen from the abactinal pole, c, circumscribed area; I 1 , I s , I*, Z 5 , lateral 

ambulacra ; I", I 3 , I 6 , f, anterior and posterior ambulacra. 





40 DISCOPIIOR^E. 

Idyiopsis affinis AGASS. 

Idyiopsis affinis AGASS. Cont. Nat. Hist. U. S., III. pp. 288, 296. 1860. 

Gulf of Mexico, Tortugas, and Florida (L. Agassiz). 



OKDEK DISCOPHOR^ ESCH. 

Medusarice LAMK. (/?./>) 1816. 

Meduses PER. et LES. (p. p.). 1809. 

Discophorcc planerocarpce ESCH. Syst. d. Acal. 1829. 

Discophorcv cri/ptocarpce ESCH. Syst. d. Acal. 1829. 

Pulmograda BL. (p. p.). Manuel d'Actinologie. 1830. 

Medusidce BR. (p. p.). Mem. Acad. St. Petersb. 1833. 

Medusae LESS. (p. jo.) Zooph. Acal. 1843. 

Steganophihalma FORBES. Brit. Nak. Medusas. 1848. 

Acraspeda GEGENB. Syst. d. Med. ; in Z. f. AV. Zool. 1856. 

Craspedota GEGENB. (p. p.). Syst. d. Med.; in Z. f. W. Zool. 1856. 

Lucernariadcc HUXL. (non Johnst.). Lectures on Genl. Nat. Hist. . . . 1856. 

Discophorce AGASS. Cont. Nat. Hist. U. S., IV. 1862. 



SUBORDER RHIZOSTOME^E AGASS. 

Rlrizostomece AGASS. Cont. Nat. Hist. U. S., Vol. IV. pp. 9, 131. 1862. 
Rhizostomidce ESCH. Syst. der Acal., p. 42. 1829. 
Polystomoe BR. Mem. Acad. St. Petersb. 1835, Prod., p. 228. 
Rhizostomidees LESS. Zooph. Acal., p. 404. 1843. 



Family RHIZOSTOMIDCE Esch. 

Rhizostomidce ESCH. Syst. der Acal., p. 42. 1829. 

Rhizostomidce AGASS. Cont. Nat. Hist. U. S., Vol. IV. p. 149. 1862. 



STOMOLOPHUS AGASS. 

Stomolophus AGASS. Cont. Nat. Hist. U. S., Vol. IV. pp. 138, 151. 1862. 

Stomolophus meleagris AGASS. 

Stomolophus meleagris AGASS. Cont. Nat. Hist. U. S., Vol. IV. pp. 138, 151 ; HI. PL 14. 
Cephea rhizostoma GIBBES (non Lamk.). Fauna of South Carolina. 1847. 

Atlantic Ocean, coast of Georgia. 

Catalogue No. 335, Warsaw Shoals, Georgia, L. Agassiz. 

Museum diagram No. 8 after L. Agassiz. 



SEM^EOSTOME^E. 41 

Family POLYCLONIDjE Agass. 

Polyclonidce AGASS. Cont. Nat. Hist. U. S., Vol. IV. pp. 140, 159. 1862. 

POLYCLONIA BR. 

Polydonia BR. Mem. Aoad. St. Petersburg, p. 396, Pis. 21-23. 1838. 
Polydonia AGASS. Cont. Nat. Hist. U. S., IV. p. 139. 1862. 

Polyclonia frondosa AGASS. 

Polydonia frondosa AGASS. Cont. Nat. Hist. U. S., Vol. IV. pp. 139, 159, HI. Pis. 13, 13". 

Medusa frondosa PALL. Spicil. Zool., p. 30, PL 2, Figs. 1-3. 

Cassiopea frondosa LAMK. (non Til.). Anim. s. Vert., H. p. 512. 

Cassiopea frondosa ESCH. Syst. d. Acal., p. 43. 1829. 

Cassiopea Pallas PER. et LES. Hist. Gen. d. Med. ; in An. Mus., XIV. p. 45. 

Medusa frondosa Bosc. Hist. Nat. d. Vers., II. p. 170. 

Cassiopea frondosa LESS. Zooph. Acal., p. 405. 1843. 

West Indies (Pallas) ; Florida, Key West, and Key Largo (L. Agassiz). 

Cat. No. 332, Tortugas, Fla., March, 1858, L. Agassiz. 

Cat. No. 333, Key West, Fla., March, 1858, L. Agassiz and J. E. Mills. 

Cat No. 334, Key West, Fla., March, 1858, L. Agassiz and J. E. Mills. 

Cat. No. 346, Florida, L. Agassiz. 

Cat. No. 383, Havana, Professor F. Poey. 

Museum diagram No. 8, after L. Agassiz. 

SUBORDER SEM^EOSTOME^E AGASS. 

Semceostomece AGASS. Cont. Nat. Hist. U. S., Vol. IV. pp. 9, 159. 1862. 

Family AURELIADJE Agass. 

Aureliadce AGASS. Cont. Nat. Hist. U. S., Vol. IV. pp. 80, 159. 1862. 

AURELIA PER. et LES. 

Aurelia PER. et LES. Ann. du Mus., XIV. p. 45. 1809. 
Aurelia LESS. Zooph. Acal., p. 348. 1843. 
Aurelia AGASS. Cont. Nat. Hist. U. S., IV. p. 159. 1862. 
Medusa LINN. Faun. Suec., p. 511. 
Medusa ESCH. Syst. der Acal., p. 61. 1829. 
Ephyra PER. et LES. Hist. Gen. des Med., p. 42. 
Ocyroe PER. et LES. Hist. Gen. des Med., p. 43. 
Evayora PER. et LES. Hist. Gen. des Med., p. 31. 
Scypliistoma SARS. Bidrag til Soedyrenes Nat. 1829. 
Rhizostoma ESCH. Syst. d. Acal., p. 45. 1829. 
Strolila SARS. Beskriv. . . . over Polyp, ... p. 16. 1835. 
Diplocraspedon BR. Prod. Mem. Acad. St. Petersburg, p. 226. 1835. 
Monocraspedon BR. Prod. Mem. Acad. St. Petersburg, p. 225. 1835. 
Claustra LESS. Zooph. Acal., p. 378. 1843. 
Biblis LESS. Zooph. Acal., p. 339. 1843. 
KO. II. 6 



42 



AURELIA FLAVIDULA. 




Aurelia flavidula PER. et LES. 

Amelia flavidula PER. et LES. Ann. Mus., XIV. p. 47. 1809. 

Aurelia flavidula LESS. Zooph. Acal., p. 376. 1843. 

Medusa aurita FAB. Faun. Gron., No. 356. 1780. 

Aurelia aurita GOULD. Rep. Inv. Mass., p. 348. 1841. 

Aurelia flavidula GOULD. Rep. Inv. Mass., p. 348. 1841. 

Epliyra octolobata GOULD. Rep. Inv. Mass., p. 348. 1841. 

Aurelia aurita STIMPS. Mar. Inv. Grand Manan, p. 11. 1853. 

Aurelia aurita MORCH ; in Nat. Bid. til en Besk. af Gronl., p. 95. 1857. 

Aurelia sex-ovariis MORCH ; in Nat. Bid. til en Besk. af Gronl., p 95. 1857. 

Aurelia flavidula AGASS. Cont. Nat. Hist. U. S., III. Pis. 6, 7, 8, 9, 11, IP, 11"; PI. 10, Figs. 18, 

22, 31, 32, 36 ; PI. 10% Figs. 4, 13, 15% 16-41 ; PI. 11% Figs. 1-13 ; IV. pp. 10, 160. 
Aurelia flavidula PACKARD. A List of Animals . . . 1863. 

g- 65. Occurs from March to the 

end of October ; they collect 
together, and form large 
banks at the spawning sea- 
son. Professor Agassiz has 
already spoken of the possi- 
bility of this species proving 
identical with the Northern 
European Aurelia aurita. 
But this, as well as the 
identity of Cyanea arctica 
with the European represent- 
ative, can only be decided 
after renewed examination 
of these species. 

Figs. 65, 66 are copied 
from Professor Agassiz's Con- 
tributions ; they give a pro- 
file, and a view from the ab- 
actinal pole, of our Aurelia. 

Greenland (Fabricius) ; 
New England (Gould, Ag- 
assiz). 



Fig. 66. 




a 



Cat. No. 337, Nahant, 1861, L. Agassiz. 

Cat. No. 338, Nahant, 1861, A. Agassiz. 

Cat. No. 339, Nahant, 1858, L. Agassiz. 

Cat. No. 340, Boston, 1862, H. J. Clark. 

Cat. No. 341, Trenton, Me., 1860, Verrill and Shaler. 

Cat. No. 347, Boston, 1862, H. J. Clark. 

Cat, No. 367, Gulf of St. Lawrence, 1861, Anticosti Expedition. 

Museum diagrams Nos. 9, 10, 11, after L. Agassiz. 

Fig. 65 is a profile view of Aurelia flavidula, much reduced. 

Fig. 66 an abactinal view of Aurelia flavidula. I, II, III, IV, are the ambulacral zones ; A, B, 
c, D, the interambulacral zones ; 1,2, 3, 4, a, b, the respective halves of these systems. 



STHENONLE. 43 



Alirelia labiata CHAM, et EYSEN. 

Aurelia labiata CHAM, et EYSENH. N. Acta, X. p. 358, PI. 38, Fig. 1. 

Medusa labiata ESCH. Syst. d. Acal., p. 64. 1829. 

Ocyroe labiata BL. Man. d'Actinol., PI. 42, Figs. 1, 2. 1834. 

Aurelia labiata LESS. Zooph. Acal., p. 377. 1843. 

Aurelia labiata AGASS. Cont. Nat. Hist. U. S., IV. p. 160. 1862. 

Many of the Discophone of the southern part of the Northwest Coast 
must breed during the whole year, as I have found the adult with the 
ovaries fully developed during nearly every month of the year, in the 
harbor of San Francisco. This is at least the case with Phacellophora 
and Aurelia, which are the two most common genera of the harbor of 
San Francisco. Further north, however, in the Gulf of Georgia, the 
Discophorre pass the winter in their hydra state. 

North California (Cham, and Eysen.) ; California (Eschscholtz) ; San 
Francisco Bay (A. Agassiz). 

Aurelia marginalis AGASS. 

Aurelia marginalis AGASS. Cont. Nat. Hist. U. S., IV. pp. 86, 160. 1862. 

Florida, Key West (L. Agassiz). 

Cat. No. 352, Key West, Fla., L. Agassiz. 



Family STHENONI^E Agass. 

Sthenonice AGASS. Cont. Nat. Hist. U. S., Vol. IV. pp. 115, 161. 1862. 

HECC^DECOMMA BR. 

Hecccedecomma BRANDT. Mem. Acad. St. Petersb., p. 300. 1838. 
Hecccedecomma AGASS. Cont. Nat. Hist. U. S., IV. p. 161. 1862. 

Heccaedecomma ambiguum BR. 

Hecccedecomma ambiguum BR. Mem. Acad. St. Petersb., p. 300, Pis. 27, 28. 1838. 
Heccaedecomma ambiguum AGASS. Cont. Nat. Hist. U. S., IV. p. 161. 1862. 
Cyanea ambigua LESS. Zooph. Acal., p. 388. 1843. 

A species of this genus was observed in the Straits of Fuca, agreeing 
with the description and figures of Mertens so closely, that it is prob- 
able he observed this same species on the coast of Russian North 
America, 

Port Townshend, W. T. (A. Agassiz). 



44 CYANEIM:. 



PHACELLOPHORA BR, 

Phacellophora BR. (non Huxl.). Prod. Mem. Acad. St. Pet., p. 223, 1835. 
Phacellophora LESS. Zooph. Acal., p. 343. 1843. 
Phacellophora AGASS. Cont. Nat. Hist. U. S., IV. p. 161. 1862. 



Phacellophora camtschatica BR. 

Phacellophora camtscJiatica BR. Mem. Acad. St. Petersb., p. 366, PI. 8. 1838. 
Phacellophora eamtschatica LESS. Zooph. Acal., p. 344. 1843. 
Pliacellophora eamtschatica AGASS. Cont. Nat. Hist. U. S., IV. p. 161. 1862. 

The number of species of large Discophorous Medusae found on the 
western coast of North America gives to the Acalephian Fauna of 
California a very characteristic stamp, when compared with that of 
the eastern coast. 

Petropaulowsk (Mertens) ; San Francisco Bay (A. Agassiz). 



Family CYANEID^E Agass. 

Cyaneidce AGASS. Cont. Nat. Hist. U. S., Vol. IV. pp. 114, 161. 1862. 

CYANEA PER. et LES. 

Cyanea PER. et LES. Ann. du Mus., XIV. p. 51. 1809. 

Ci/anea ESCH. Syst. der Acal., p. 67. 1829. 

Cyanea Cuv. Reg. An. 1818. 

Cyanea LESS. Zooph. Acal., p. 379. 1843. 

Cyanea AGASS. Cout. Nat. Hist. U. S., Vol. IV. p. 161. 1862. 

Cyanea arctica PER. et LES. 

Ci/anea arctica PER. et LES. Ann. Mus., XIV. p. 51. 1809. 

Cyanea arctica AGASS. Cont. Nat. Hist. U. S., IV. pp. 87, 162; Vol. HI., Pis. 3, 4, 5, 5 s ; PI. 10, 

Figs. 1-17, 19-21, 23-30, 33-35, 37-38 ; PI. 10% Figs. 1 -4% 5-12% 14, 15, 17-40. 
Medusa capillata FAB. (non Lin.) Faun. Groenl. No. 358. 1 780. 
Cyanea Postelsii GOULD (lion Br.). Rep. Inv. Mass., p. 347. 
Cyanea Postelsii STIMPS. Mar. Inv. Grand Manan, p. 11. 1853. 
Cyanea arctica MORCH. In Naturh. Bid. til en Besk. af Gronl., p. 95. 1857. 
Cyanea arctica PACKARD. Canad. Nat. Dec. 1863. 

This species attains an enormous size. I measured myself a speci- 
men at Nahant, the disk of which had attained a diameter of seven and 
a hah feet, the tentacles extending to a length of more than one 
hundred and twenty feet. Our total ignorance of the young of these 
large Discophorre is due to their peculiar habits. As has already been 
suggested, they probably remain a great part of the time groping about 



CYANEA ARCTICA. 



45 



the bottom of the sea, apparently coming to the surface only in their 
adult condition. Having accidentally visited the wharves of Province- 



Fi S . 67. 




town harbor early one morning, between four and five, I was aston- 
ished to perceive what a large number of young Cyaneas were floating 

Fig, 67. Cyanea arctica very much reduced. The tentacles are cut off for want of room. 



46 CYANEA VERSICOLOR. 

about, measuring all the way from a quarter of an inch to three inches 
in diameter. On my return to the same place at seven o'clock, al- 
though not a breath of air had ruffled the surface, they had all re- 
turned to deeper water. The early habits of the young Cyanea may 
be only one of many similar instances of early rising among Acalephs. 
Fig. 67 is copied from the Contributions of Professor Agassiz. 

Greenland (Fabricius) ; Northeastern Coast of America, from Bay of 
Fundy to Boston Harbor (Gould, Agassiz) ; Long Island Sound, Vine- 
yard Sound (A. Agassiz). 

Cat. No. 326, Chelsea Beach, Oct. 1851, L. Agassiz. 

Cat. No. 327, Nahant, Aug. 1858, L. Agassiz. 

Cat. No. 328, Nahant, Aug. 1858, L. Agassiz. 

Cat. No. 369, Gulf of St. Lawrence, 1861, Anticosti Expedition. 

Museum diagrams Nos. 12, 13, after L. Agassiz. 



Cyanea fulva AGASS. 

Cyanea fulm AGASS. Cont, Nat. Hist. U. S., IV. pp. 119, 162. 18G2. 

The youngest specimen of Cyanea which has been observed meas- 
ured about one third of an inch in diameter. Its peculiar habit of 
always remaining at the bottom of the vessel in which it w r as kept, 
seemed to explain until the observations, above mentioned, of the 
early habits of Cyanea arctica the periodic appearance of adult 
Medusae at certain times of the year, simply for the purpose of spawn- 
ing, while for the remainder of their life they remain groping near 
the bottom. In general appearance the young Cyanea resembles the 
Cyaneida3. It has but few marginal tentacles, the centre one being 
developed far above the others ; the separate lobes of the actinostome 
are, however, distinct, and do not form the inextricable mass of curtains 
surrounding the actinostome of a Cyanea. The digitate appendages 
are developed in pairs on each side of a median line, indicating the 
position of the future genital organs. This gives us at once the rela- 
tive position of the Cyaneidse and Pelagidse, the latter being only per- 
manent forms resembling somewhat embryonic Cyaneidse. 

Long Island Sound (L. Agassiz) ; Vineyard Sound (A. Agassiz). 

Cat. No. 331, Naushon, A. Agassiz, Sept. 1861. Young. 

Cyanea versicolor AGASS. 

Cyanea versicolor AGASS. Cont, Nat. Hist. U. S., IV. pp. 119, 162. 1862. 

South Carolina (L. Agassiz). 

Cat. No. 329, Charleston, S. C., 1852, L. Agassiz. 



PELAGIM;. 



47 



Young ? 



Cyanea Postelsii 

Cyanea Poxtelsi'i BR. Mem. Ac. St. Pet., p. 375, PI. 12, 13, 13*. 1838. 
Cyanea Postelsii AGASS. Cont. Nat. Hist. U. S., IV. p. 1G2. 1862. 
Cyaneopsis beliring/ana BR. Mem. Ac. St. Pet., PI. 11, Fig. 1. 1838. 
? Cyanea ferruginea ESCH. Syst. d. Acal., p. 70. 1829. 
Cyanea Postelsii LESS. Zooph. Acal., p. 387. 1843. 

This species is extremely abundant during the Fall, in the Gulf of 
Georgia and the Straits of Fuca, and rivals in size its representative on 
the eastern shores of North America, 

Kamtschatka, Aleutian Islands, and Western Coast of North America 
(Eschscholtz) ; North Pacific, Norfolk Sound, between Sitka and Una- 
laschka (Mertens) ; Port Townsend, W. T. (A. Agassiz). 



Family PELAGID^E Geg. 

Pelagidce GEGENB. Zeitsch. f. Wiss. Zool., VIII. p. 210. 1856. 
Pelagidce AGASS. Cont. Nat. Hist. U. S., IV. pp. 121, 163. 1862. 



PELAGIA PER. et LES. 

Pelagia PER. et LES. Ann. du Mus., XIV. p. 37. 1809. 

Pelagia ESCH. Syst, der Acal., p. 72. 1829. 

Pelagia LESS. Zooph. Acal., p. 388. 1843. 

Pelagia AGASS. Cont. Nat. Hist. U. S., IV. p. 163. 1862. 

Diancea LAM. Syst. An. s. Vert., II. p. 507. 



Pelagia cyanella PER. et LES. 

Pelagia cyanella PER. et LES. Ann. du Mus., XIV. p. 37. 1809. 

Pelagia cyanella ESCH. Syst. der Acal., p. 75. 1829. 

Pelagia cyanella Bosc. Hist. Nat. des Vers., II. p. 140, PI. 17, Fig. 3. 

Pelagia cyanella AGASS. Cont. Nat. Hist. U. S., IV. pp. 128, 164, IH. Pis. 13, 13% PI. 12. 

Medusa pelagia SWARTZ. Konig. Vetensk. Akad. 1 788. 

Medusa pelagia LOFFLING. Reise, p. 105. 

Medusa pelagia LIN. Syst. Nat. 

Pelagia americana PER. et LES. Ann. clu Mus., XIV. p. 39. 1809. 

Pelagia noctiluca CHAM. ; in Choris' Voyage Pittoresque, p. 3. Fi s- 68 - 

Pelagia denticulata PER. et LES. Ann. du Mas., XIV. p. 38. 

Dianasa cyanella LAMK. An. s. Verteb., II. p. 507. 

Diancea denticulata LAMK. An. s. Verteb., H. p. 507. 

This species (Fig. 68) is found along the Florida 
Keef. In this genus the eggs develop directly into 
the young Medusie, and the embryos are never at- 
tached to the ground. 

Caribbean Sea (Swartz, Loffling) ; Coast of Florida, 
Tortugas (L. Agassiz). 

Fig. 68. Pelagia cyanella Per. et Les. (copied from Agassiz's Conti-ibutions). a, umbrella ; 
m, actinul appendages ; 7, marginal tentacles. 




48 



DACTYLOMETRA. 



Pelagia Brandtii AGASS. 

Pelagia Brandtii AGASS. Cont. Nat. Hist. U. S., IV. p. 164. 1862. 

Pelagia denticulata BR. (non Per. et Les.). Mein. Acad. St. Pet., p. 383, PI. 14, Fig. 2. 1838. 

Aleutian Islands (Mertens). 



DACTYLOMETRA AGASS. 

Dactylometra AGASS. Cont. Nat. Hist. U. S., IV. pp. 125, 166. 1863. 
Chrysaora ESCH. (p-p-)- Syst. d. Acal., p. 78. 1829. 



Fig 69. 



Dactylometra quinquecirra AGASS. 

Dactylometra quinquecirra AGASS. Cont. Nat. Hist. U. S., IV. pp. 125, 166. 1862. 
Pelagia quinquecirra DES. Proc. Bost. Soc. N. H., p. 76. 1848. 

Mr. Desor has described, in the Proceedings of the Boston Society of 
Natural History, a Pelagia under the name of P. quinquecirra; as his 
description is hardly sufficient to enable one to recognize it, I add 

the following particulars, on the 
supposition that the Pelagia which 
I found at Naushon is identical 
with the one described by Mr. 
Desor. 

Several specimens of this Pela- 
gia were taken at Naushon, the 
disk measuring from four to eight 
inches in transverse diameter, and 
one and a quarter to two inches in 
height. The general color of the 
disk is yellowish blue, the surface 
being covered with reddish-brown 
spots (Fig. 69), crowded more 
thickly towards the abactinal pole. 
The spotted surface does not reach 
the margin of the disk only dot- 
ted lines extend from the lobes un- 
til they are lost in the more numer- 
ous spots of the central part. The 
marginal tentacles have the same 
color as the spots of the disk. 
There are five between each of the eight eyes, arranged, one, the 
largest, in the middle of the broader central lobe, and one on each side 

Fig. 69. Dactylometra quinquecirra Agass. one fourth the natural size. 




DACTYLOMETRA QUINQUECIRRA. 49 

of the smaller lobe, the shorter tentacles being placed nearest the eyes. 
There are eight marginal lobes in which the eyes are placed, eight 
large lobes in the middle of the space between the eyes, from which the 
large tentacles arise, and the space between this large lobe and the 
lobe of the eye is occupied by the small lobes on the sides of which 
the smaller marginal tentacles are placed, making in all thirty-two 
marginal lobes. The fringes of the actinostome extend in four simple 
thick lobes, with frilled edges, about twice the length of the transverse 
diameter ; they are flesh color. The ovaries are seen from above as 
four large yellow bunches. These Medusae are nocturnal in their hab- 
its ; they are only occasionally found floating at the surface during the 
day, while at night, in the same localities, the bottom swarms with 
these large masses of dull phosphorescence, moving about with the 
greatest rapidity. When kept in tanks, they remain torpid during the 
day at the bottom of the jars, and when night comes on begin to 
become more animated, and soon move briskly about, emitting a dull 
phosphorescent light. This Pelagia is always accompanied by a spe- 
cies of Clupeoid, found in the folds of the fringes of the actinostome, 
moving along with the jelly-fish, which, when they are pushed off 
accidentally, rush back to their place of shelter. From twenty to thirty 
specimens have been found swimming in the fringes of the actinostome. 
It is strange that the fish should go there for shelter, for every once in 
a while one of them pays the penalty by being swallowed, without this 
disturbing the others in the least ; they in their turn find food in the 
lobes of the actinostome, and even eat the folds themselves, until their 
turn comes to be used as food. I have seen in this way three fishes 
eaten during the course of as many days. The specimens measured 
about an inch in length. Sars, Leuckart, and Peach have observed this 
same kind of parasitism of certain species of fishes upon other Dis- 
cophoroe. Nor is this limited to Acalephs ; some species of Holothu- 
rians, and even a Culcita, are said to give refuge to fishes. 

It is somewhat strange that almost all the Medusae which have been 
observed are found in the brighest sunshine only, or in very dark 
nights. Early in the morning, and till about ten o'clock, even on clear 
days, Medusae do not make then: appearance, while from eleven till one 
or two o'clock they can be caught in abundance. After that time they 
disappear gradually, and late in the afternoon, towards sunset, it is rare 
to see a single jelly-fish. Between nine and twelve o'clock at night, 
they come to the surface again ; and that hour, in fact, is one of the 
most favorable for collecting, in spite of the darkness. 

Nantucket Bay (Desor) ; Naushon (A. Agassiz) ; between Bermudas 
and Azores (J. Dray ton). 

Cat. No. 343, Naushon, Mass., Sept. 1861, A. Agassiz. 

Cat. No. 388, Bermudas, A. S. Bickinore. 



NO. II. 



50 MELANASTER. 



POLYBOSTRICHA BR. 

Polybostricha BR. Mem. Acad. St. Petersb., p. 384. 1838. 
Polybostricha AGASS. Cont. Nat. Hist. U. S., IV. pp. 126, 166. 1862. 

The species of Polybostricha and Melanaster which are here enumer- 
ated were observed during a calm off the bar of San Francisco ; and 
although tolerably accurate notes were taken at the time, yet they are 
not sufficient to warrant the description of these species under new 
names. They are therefore mentioned here more for the sake of the 
geographical distribution of these genera ; and as some of the marine 
animals of Kamtschatka are found on the coast of California, it is 
no means improbable that the species I have referred to the figures ol 
Brandt will prove, on closer examination, to be identical with them. 



Polybostricha helvola BR. 

Polybostricha helvola BR. Mem. Acad. St. Petersb., PL 15, p. 384. 1838. 
Polybostricha helvola AGASS. Cont. Nat. Hist. U. S., IV. p. 166. 1862. 
Chrysaora helvola LESS. Zooph. Acal., p. 402. 1843. 
Polybostricha sp. A. AGASS. ; in Agassiz's Cont. Nat. Hist. U. S., IV. p. 166. 

Aleutian Islands, Sitka (Mertens) ; Punta de los Reyes, California 

(A. Agassiz). 



MELANASTER AGASS. 

Melanaster AGASS. Cont. Nat. Hist, U. S., IV. pp. 126, 166. 1862. 
Chrysaora BR. (p. p.). Mem. Acad. St. Petersb., p. 385. 1838. 



Melanaster Mertensii AGASS. 

Melanaster Mertensii AGASS. Cont. Nat. Hist. U. S., IV. p. 166. 1862. 
Chrysaora melanaster BR. Mem. Acad. St. Petersb., Pis. 16, 17, p. 385. 1838. 
Chrysaora melanaster LESS. Zooph. Acal., p. 403. 1843. 
Melanaster sp. A. AGASS. ; in Agassiz's Cont. Nat. Hist. U. S., IV. p. 166. 1862. 

Kamtschatka and Avatska Bay (Mertens) ; off San Francisco Bar 

(A. Agassiz). 



HAPLOSTOME.E. 51 

SUBORDER HAPLOSTOME^ AGASS. 

Haplostomece AGASS. (excl. Luccrnarice A. AG.). Cont. Nat, Hist. U. S., IV. p. 167. 18G2. 

Family THAL ASS ANTHER Less. 

Thalassanthece. LESS. Zooph. Aeal, p. 298. 1843. 
Tf/alasaanthece AGASS. Cont. Nat, Hist. U. S., IV. p. 167. 1862. 
JErjlnidiK GEGENB. Zeits.. f. W. Zool., VIII. p. 258. 1856. 
JEyinidce McCR. Gynin. Charl. Harb., p. 107. 

FOVEOLIA PER. et LES. 

FoveoHa PER. ct LES. Ann. clu Mus., XIV. p. 27. 1809. 
Foveolia AGASS. Cont, Nat, Hist, U. S., IV. p. 1G8. 1862. 
Cunina ESCH. Syst. d. Acal., p. 116. 1829. 
Cunina BL. Man. d'Actinol., p. 279. 1834. 
Cunina LESS. Zooph. Acal., p. 301. 1843. 
Cunina LAMK. Syst, Anim. s. Vert., III. p. 142. 
Cunina GEGEXB. Zeit. f. Wiss. Zool., p. 259. 1856. 
Cunina McCR. Proc. Elliot Soc., p. 108. 1857. 

Foveolia octonaria A. AGASS. 

Cunina octonaria McCR. Proc. Elliot Soc., PI. XII. Figs. 4, 5, p. 109. 

Cunina octonaria AGASS. Cont. Nat, Hist. U. S., IV. p. 168. 18G2. 

Cunina octonaria McCR. Pis. 4, 5, 6, 7, for Embryolog. Hist. ; Elliot Soc., pp. 1 - 36. 1856. 

Charleston, S. C. (McCrady). 

Museum diagram No. 15, after McCrady. 

CAMPANELLA BL. 

Campanella BL. (non Less.). Man. d'Actin., p. 286. 1R34. 
Campanella AGASS. Cont. Nat. Hist. U. S., IV. p. 169. 1862. 
^Eyinopsis J. MULL, (non Br.). Airhiv f. Anat., p. 272. 1851. 

Fritz Miiller was the first to show (Wieg. Archiv., 1861) that the 
position of the ^Eginidse and Charybdeidas among the Hydroids was 
not a natural one. He proposed for the reception of these groups a 
new division equivalent to the Discophorae and Hydroids. But as he 
considers the Ctenophorse and Hydromedusae as the two great divisions 
of the Acalephs, his group of ^Egineae would hold very nearly the same 
rank as that which we are induced to assign to it here, - - that of a 
suborder among Discophorae. From the examination of the only spe- 
cies of Campanella thus far found on our coast, and a comparison 



52 CAMPANELLA PACHYDERMA. 

with the two species of Trachynema here enumerated, I am inclined to 
add, near this suborder, two other families, the position of which in the 
different systems of classification has always been a great puzzle. I 
mean the Trachyneinidce and the Geryonidse (Persa, Aglauridce).* The 
peculiar solid character of the bell of these families, incapable of con- 
traction to any extent, is in striking contrast with the transparent filmy 
disk of the true Hydroids, reminding us of the solid mass of the larger 
Discophorae. The character of the development, also, which takes 
place directly from the egg, differs from that of the true Hydroids, 
and we should thus remove from them those Jelly-fishes which do not 
pass through an alternate generation. The peculiar character of the 
marginal appendages of the Trachynemidne, so different from anything 
found among the true Hydroids, and which resemble so closely those 
of the Charybdeidoa, is another character in favor of this division, as 
well as the nature of the veil, which is a thick, solid, folded membrane, 
approaching somewhat in character the actinal pouches formed by the 
veil of Campanella. 

Campanella pachyderma A. AGASS. 

This small Medusa is particularly interesting on account of the light- 
it throws on the systematic position of the JEginidae. Having the gen- 
eral appearance of the ./Eginida?, it has, however, distinctly marked 
radiating and circular tubes ; the genital organs are developed, as in 
that family, in horseshoe-shaped pouches arranged round the base of 
the proboscis, which projects through a small space left by the pendent 
folds of the veil beyond the level of its actinal surface. The circular 
tube is thus apparently placed at nearly one third of the height of the 
bell, owing to the great expansion of the eight lobes of the lower floor. 
The veil is attached at the inner extremity near the genital pouches, 
and between every two of the chymiferous tubes it is drawn up, form- 
ing a distinctly marked indentation. The position of the genital pouches 
is very similar to what we find among other Discophoraa, as the Lucer- 
nariae and Cuninida?, for instance, where they form an elongated lobed 
rosette round the centre. The genital pouches extend in a continuous 
line round the base of the proboscis. The shape of the bell is a some- 
what depressed hemisphere, flaring slightly at the base ; the tentacles 
are carried somewhat stiffly (Fig. 70), and are capable of but limited 
contraction and expansion ; the proboscis equals in length the height 
of the bell ; it is conical, and terminates in a smooth opening. The 
veil is not very opaque, and when the medusa is seen from the actinal 
side (Figs. 71, 72), the chymiferous tubes, as well as the circular tube, 

* From the figure given by Gegonbanr of the pedunculated marginal bodies in Aglaura, the 
affinity to Traehynema (Circe) is unquestionable. 



CAMPANELLA PACHYDERMA. 



53 



can readily be seen through its thickness. The bell itself is of a dirty 
yellowish color, with dark sorrel-colored spots scattered thickly over its 



Fig. 71. 



Fig. 70. 




Fig. 72. 





surface ; these pigment spots are similar to the little bunches of lasso 
cells found 011 the surface of Aurelia. The pouches are capable of 



Fig. 73. 



Fig. 75. 






expansion and contraction, as it will often be seen that the proboscis 
has considerable play when the pouches are thrown out beyond the 

Fig. 70. Profile view of Carapanella. 

Fig. 71. Actinal view of Fig. 70 ; the tentacles are cut off. 

Fig. 72 is a somewhat more magnified view of Fig. 71, in which the pouches are thrown out 
beyond the circular tube, p is the outer wall of the proboscis ; g, the genital pouches ; /, the place 
of attachment of the veil, as seen from the actinal side ; _/', one of the pouches formed by the veil ; 
f", the part of the veil intermediate between two pouches ; /, the base of a tentacle. 

Fig. 73 is a view of a part of the actinal surface in the condition of Fig. 71, when the pouches 
are drawn closely round the proboscis ; lettering as in Fig. 72. p', interior of proboscis. 

Fig. 74 is a magnified profile view of a portion of the base of a tentacle, c, the circular tube ; 
t', the chymiferous tube ; />", the pigment spot on lower surface of bulb ; m, the upper part of sen- 
sitive bulb, in which pigment cells are loosely scattered. 

Fig. 75. View of basal portion of tentacle, seen from above ; lettering as in Fig. 74. /, clus- 
ters of lasso cells ; o, outer wall of bulb. 



54 TRACHYNEMIDJE. 

margin of the circular tube (Fig. 72), while at other times it is closely 
hemmed in on all sides. (Fig. 73.) The base of the tentacles swells 
out above and below the chymiferous tube, forming a large bulb, in the 
upper portion of which pigment-cells of a brownish-red color (Fig. 73, m) 
are loosely scattered, while in the lower portion (Figs. 74, 75, p"} a 
dark concentrated pigment-spot is found. The tentacles are hollow, 
and are surrounded for their whole length by clusters of lasso cells 
(Fig. 75, I) similar to those of young Tubularian Medusie, such as 
Coryne and Syndiction. 

The size of this Medusa is about one twentieth of an inch in diameter. 

Found at Nahant, September, Alex. Agassiz. 

Museum diagram No. 1C, after Alex. Agassiz. 



^GINOPSIS Bn. 

JEcfmopds BR. (non ,1. Miiller). Prod. Mem. Acad. St. Petersburg, p. 222. 1835. 
sEginopsi* AGASS. Cont. Nat. Hist. U. S., IV. p. 170. 1862. 
JEyinopsis LESS. Zooph. Acal., p. 304. 1843. 



Laurentii BR. 

JEginopsis Laurentii BR. Mem. Ac. St. Peters!)., PI. 0, p. 363. 1838. 

JEyinopsix Laurentii LESS. Zooph. Acal., p. 304. 1843. 

jEginopsis Laurentii AGASS. Cont. Nat. Hist. U. S., IV. p. 170. 1862. 

Laurent Bay, Behring's Straits (Mertens). 



SUBORDER TRACHYNEMID^E A. AGASS. 

Forbes, in his Natural History of the British Naked-eyed Medusae, 
characterized as a family the Circeidse ; at that time only a few other 
species of this group were known, but so imperfectly described that 
even at the present day the natural affinities of these Medusce are far 
from being well ascertained. Gegenbaur, who has studied Medusae 
which I suppose to be only the young of closely allied forms, has also 
separated his young Medusae as a distinct family, under the name of 
Trachynemidse. The Diancea conica of Lesson may even prove to be 
the adult of his Trachynema ciliahtm, as it is evident from the draw- 
ing of Lesson* that he has figured there a Medusa closely allied to 
Circe Forbes, and perhaps identical with it, A comparison of Trachy- 
nema ciUatwn (Geg. PL IX. Fig. 6) with the young specimens of Circe 
here figured, will show the close affinity of these two Medusae. The 
family name of Trachynemidae ought therefore yield to that proposed 

* Ann. Scien. Nat., Vol. X. PI. 6, Fig. 3. 



TRACIIYNEMA CAMTSCHATICUM. 55 

by Forbes ; unfortunately, the name Circe had already been applied to 
a genus of Mollusks, before Brandt proposed it in 1838, and we have 
therefore retained the name of Gegenbaur. Gegenbaur placed these 
Medusae in the vicinity of the Eucopidse ; but a close examination of 
their characters, to which I have already referred when speaking of 
Campanella, leads us to remove them as well as the AglauridsB, 
Geryonida?, and Leuckartidse to the Discophorse Haplostomeae, as a 
separate suborder closely allied to the ^Eginidae. Dr. Fritz Miiller, 
to whom I had suggested the probability of Circe being the adult of 
Trachynema, says, in one of his letters, that he has found Trachynema 
near Desterro ; " in consequence of this, it is highly probable that they 
are the young of Tamoia, never having met with Circe on our coast." 
If this should prove to be the case, we have a very strong argument 
in favor of joining the Trachynemidse (Circeans) with the Discophorse. 



Family TRACHYNEMIDSE Gegenb, 

Trachynemidce GEGEXB. Zeit. f. Wiss. Zool., VIII. p. 249. 1856. 
Circeidce FORBES. Brit. Naked-eyed Medusas, p. 34. 1848. 
Circeidce AGASS. Cont. Nat. Hist. U. S., IV. p. 348. 1862. 
Trachynemidce AGASS. Cont. Nat. Hist. U. S., IV. p. 365. 1862. 



TRACHYNEMA GEGENB. 

TracJiynema GEGEXB. Generationswechsel, p. 50. 1854. 

Circe MERTEXS. Br. Me'm. Acad. St. Petersb., p. 219. 1835. (Preoccupied in Moll.) 

Circe FORBES. Brit. Nak. Medusae, p. 34. 1848. 

Circe LESS. Zooph. Acal., p. 285. 1843. 

Circe AGASS. Cont. Nat. Hist. U. S., IV. p. 348. 1862. 



Trachynema camtschaticum A. AGASS. 

Circe camtschatica BR. Me'm. Acad. St. Pet., p. 354, PI. I. Figs. 1-5. 1838. 
Circe camtschatica AGASS. Cont. Nat. Hist. U. S., IV. p. 348. 1862. 
Circe camtschatica LESS. Zooph. Acal., p. 285. 1843. 
Circe impatiens AGASS. Cont. Nat. Hist. U. S., IV. p. 349. 1862. 

A few specimens of this beautiful little jelly-fish (Fig. 76) were 
caught on the shores of Galiano Island, in the Gulf of Georgia, W. T. 
The greatest diameter is situated on a level with the point of suspen- 
sion of the ovaries. The ovaries are flat, triangular-shaped (Fig. 77), 
the chymiferous tubes very slender. The solid prolongation of the 
abactinal portion of the spherosome, which extends, in the Eastern 
species, to a short distance of the actinostome, is much shorter (Fig. 
78) ; the chymiferous cavity is especially long, and extends to the 



TRACHYNEMA CAMTSCIIATICUM. 



actinal pole in the ordinary state of expansion (Figs. 76, 79) ; it is only 
slightly contractile, and terminates in four stout lappets. (Fig. 80.) 
The outline of the abactinal portion of the spherosome is conical, with 
two very slight curves, one immediately above the point where the 



Fig. 70. 





Fig. 79. 



Fig. 78. 





Fig. 80. c 




chymiferous tubes turn towards the actinal pole, along the solid pro- 
longation of the spheromere, and the other nearer the abactinal pole. 
The outline of the spherosome bends very suddenly towards the abac- 
tinal pole immediately above the point of attachment of the ovaries, 
somewhat as we have it in younger specimens of Trachy- 
nema. The number of spheromeres is eight, and that of 
the oral appendages four. The ambulacral tentacles (40 
to 48) are rather contractile, and when contracted appear 
as if they had been knotted. The general color is very 
pale pink ; the ovaries, ambulacral tentacles, and the pro- 
boscis being of a light-brown color. Although generally 
this medusa moves very slowly, when disturbed its movements are very 
rapid; and instead of continuing in the same direction, the animal draws 
all its tentacles inside of the actinal veil, and then suddenly throws them 
out again, this contraction turning the medusa almost upside down, and 
starts off in nearly the opposite direction from that which it had previ- 
ously pursued. This species was only seen during a short time in July. 
The drawing of Brandt seems to have misled Forbes ; he speaks of 
the want of ocelli of the British species as distinguishing it from the 
C. camtschatica ; what Forbes has taken for ocelli are only sections of 
the chymiferous tubes leading into the peripheric tube. 

Kamtschatka (Mertens) ; Galiano Island, Gulf of Georgia, W. T. 
(Alex. Agassiz). 

Cat. No. 282, Gulf of Georgia, W. T., 1859, A. Agassiz. 

Fig. 76. Profile view of Trachynema camtschaticuni, slightly magnified. 

Fig. 77. One of the genital organs, g, point of attachment to chymiferous tube. 

Fig. 78. Section of Trachynema to show the size of the gelatinous prolongation, p, and the 
mode of attachment of the genital organs, g. 

Fig. 79. Chymiferous cavity of Trachynema at the end of the gelatinous proboscis. 

Fig. 80. View of Trachynema from above, to show the shape of the lips of the actinostome. 
r, chymiferous cavity at base of proboscis into Avhich the tubes lead ; />, gelatinous part of pro- 
boscis ; /, lips of actiuostome j o 5 opening formed by contraction of part of the chymiferous cavity. 



TRACHYNEMA DIGIT ALE. 



- 



Trachynema digitale A. AGASS. 

Medusa digitalis FAB. Faun. Groenl. No. 361. 1780. 

Tunis (Circe') digitalis MORCH (non Forbes). Bcsk. af Gronl., p. 95. 1857. 

Eirene digitale ESCH. Syst. der Acal., p. 95. 1829. 

There is considerable doubt as to the specific difference of this spe- 
cies of Trachynema from the English Circe of Forbes, and from the 
Circe camtschatica of Brandt, the series of young observed at Nahant 
being the only one which gives us any measure of the changes one 
species undergoes during its growth. It is evident from the figure of 
Forbes that the genital organs are but slightly developed ; in the north- 



rig. 82. 




western species the only specimens observed were all males, while the 
only adults of this species obtained on our coast were females. This 
question must be left undecided until we have a complete history of the 
English species. 

The adult medusa (Fig. 81) is characterized by the thinness of the 
bell, the great size of the gelatinous proboscis, which extends nearly to 

Fig. 81. Adult female Trachynema, seen in profile ; magnified. 

Fig. 82. Actinal view of the veil and circular tube of a very young Trachynema. c, c, c, c, 
tentacles opposite the chymiferous tubes ; greatly magnified. 

Fig. 83. Profile view of a part of the circular tube to show the folds of the veil, e, one of the 
pedunculated marginal capsules ; t, young tentacle ; v, folds of the veil ; somewhat more magnified 



than Fig. 82. 
NO. II. 



58 TRACHYNEMA DIGITALS. 

the level of the circular tube, and the small size of the digestive cavity. 
The eight chymiferous tubes are broad, and their course can readily be 
traced along the proboscis. The summit of the bell is quite conical ; 
the chymiferous tubes lead into a broad circular tube, opening into the 
tentacles, which are hollow ; the tentacles appear to be easily lost, as 
it is rare to obtain adult specimens in which we find anything more 
than mere stumps in the place of tentacles. I have been unable 
on this account to ascertain the normal number of tentacles in the 
adult ; they never seem to become very numerous. (See Fig. 81.) A 
tentacle is placed opposite the base of each chymiferous tube, c, c, c, . . 
Fig. 82, being a view from the actinal side of the youngest Circe 
observed ; between the chymiferous tubes there are in these young 
Medusa3 two other tentacles. We find also four marginal capsules in 
the young as well as the adult ; their number does not increase with 
age. The capsules are large, ellipsoidal, garnet-colored bodies, enclosed 
in a fold, standing out from the circular tube as if attached by a short 
peduncle, (e, Fig. 83.) The veil is thick, snugly folded at the inner mar- 
gin (Fig. 82), the larger folds extending to the circular tube. Owing to 
the slight contractility of the bell of these Medusae, they use the veil as 

Fig. 84. Fig. 85. 





their principal means of propulsion, bending it into the cavity of the 
bell, and then throwing it out with great force (see Fig. 86) ; we have 
nothing of the graceful motions of the gelatinous disk, so characteristic 
of the Hydroid Medusae. In an adult, when seen in profile, the folds 
of the veil are so thick that they are easily mistaken for rudimentary 
tentacles (v, v, Fig. 83) ; it is only when w r e see the veil turned in, or 
expanded fully outside of the bell, that their true nature is under- 
stood. In adult females, the cavity of the bell is almost filled by the 
eight sausage-like ovaries which hang down from near the upper part 
of the chymiferous tubes, almost to the extremity of the gelatinous 
proboscis. (Fig. 81.) They are of a milky color, the bell is of a slightly 
pinkish tint ; far from being transparent, it has a horny look, and be- 

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



Fig. 8.5. Trachynema somewhat more advanced than Fig. 84. 




TRACHYNEMA DIGITALS. 59 

comes wrinkled between the chymiferous tubes ; the tentacles, when 
contracted, become crimson at the extremity. 

The young Medusae are very different in shape from the adults. 
Small specimens, measuring not quite an eighth of an inch in height 
(Fig. 84), are quite globular; they have but few tentacles (Fig. 82), 
the ovaries are not developed, the gelatinous proboscis is a mere knob 
at the bottom of the bell, from which hangs down quite a long digestive 
cavity. The abactinal part of the bell projects but slightly beyond the 
general outline. It is in this stage that it resembles so closely the 
Trachynema cillatum of Gegenbaur. When Fig . 86 . 

disturbed, they carry the lips of the actinos- 
tome turned up, in a very characteristic 
manner, as Gegenbaur has figured them. 
In somewhat older specimens (Fig. 85) the 
bell has become more elongated, the tenta- 
cles more numerous, the ovaries make their 
appearance as small pouches, as in Eucope, 
and the gelatinous proboscis has extended 
somewhat into the cavity of the bell. In 
still older forms (Fig. 86) these parts have 
all taken a more prominent development, 
and we readily recognize, in the somewhat elongated bell, with the 
large proboscis and slightly pendent ovaries, the future adult Trachy- 
nema (Fig. 81), in which the development of the gelatinous proboscis, 
of the ovaries, of the tentacles, the lengthening of the bell, and its 
increase in thickness at the abactinal extremity, have been carried 
still further. The adult medusae attain a height of an inch or an inch 
and a half. 

I have identified this Medusa with the Medusa digitalis of Fabricius. 
Forbes had, in his Naked-eyed Medusoe, supposed a species of Turns to 
be identical with it ; after a careful perusal of the description of Fa- 
bricius, I am satisfied that it does not belong to the genus Turns, but 
to Circe of Brandt, or Trachynema of Gegenbaur. Morch, in his List 
of Medusae of Greenland, retains the generic name of Forbes, and makes 
it synonymous with Circe ; this is certainly a very different interpreta- 
tion of the genus Turris of Lesson from what it has received thus far 
by any writer on Acalephs. 

Baffin's Bay (Fabricius) ; Massachusetts Bay, Nahant (Alex. Agassiz). 

Cat, No. 376, Nahant, Mass., A. Agassiz. Medusae. 

Cat. No. 377, Nahant, Mass., A. Agassiz. Medusa3. 

Cat. No. 440, Nahant, Mass., A. Agassiz. Medusae. 

Museum diagram Nos. 16, after Alex. Agassiz. 

Flo;. 80. Young Tracliyncma, measuring over one third of an inch in height ; the veil is 
thrown out beyond tiie level of the circular tube. 



60 LEUCKARTIM:. 



PERSA McCR. 

Persa McCR. Gymn. Charl. Harb. 1857. 

Persa AGASS. Cont. Nat. Hist. U. S., IV. p. 349. 1862. 



Persa incolorata McCR. 

Persa incolorata McCR. Gymn. Charl. Harb., p. 104, PI. 12, Fig. 3. 1857. 
Persa incolorata AGASS. Cont. Nat. Hist. U. S., IV. p. 349. 18G2. 

Charleston Harbor (McCrady). 



Family LEUCKARTID^E Agass. 

Leuckartidce AGASS. Cont. Nat. Hist. U. S., IV. p. 364. 1862. 
Geryonidce ESCH. (p.p.). Syst. d. Acal., p. 86. 1829. 



LIRIOPE GEGENB. 

Liriope GEGENB. (non Less.). Zeit. f. W. Zool., p. 256. 1856. 

Geryonia LESS. Zooph. Acal., p. 329. 1843. 

Geryonia ESCH. (p. p.). Syst. d. Acal., 1829. (Non Per. et Les.) 

Diancea Q. and G. Voyage de PUranie, p. 566. 

Eurylia ESCH. Syst. d. Acal., p. 118. 1829. Young? 

Eurybiopsis GEGENB. Zeit. f. Wiss. Zool., p. 247. 1856. 

Liriope AGASS. Cont. Nat. Hist. U. S., IV. p. 365. 1862. 



Liriope tenuirostris AGASS. 

Liriope tenuirostris AGASS. Cont. Nat. Hist. U. S., Vol. IV. p. 365. 1862. 

Florida, Key West (L. Agassiz). 

Liriope scutigera McCR. 

Liriope scutigera McCR. Gymn. Charl. Harb., p. 106. 

Liriope scutigera AGASS. Cont. Nat. Hist. U. S., IV. p. 365. 1862. 




HSS^^^ J- n company with Liriope tenuirostris is found 
another species of Liriope (Fig. 87), which may 
prove identical with the Liriope, scutigera of 
McCrady, although it differs in the shape of the 
ovaries, which are more heartrshaped than he 
describes. The description of McCrady agrees 
better with the figure of Liriope catherinensis 
of Fritz Miiller, with which it may prove iden- 
tical. 

Charleston, S. C. (McCrady). 

Fig. 87. Liriope scutigera McCr. ? 



LUCERNARLE. 61 



SUBORDER LUCERNARI^E JOHNST. 

Lucernariadce JOHXST. (non Huxl.). Brit. Zooph., p. 244, Second Edition. 
Calycozoa LEUCK. Morphol. u. Verwandtschat't der AVirbell. Thiere, p. 20. 1848. 
Podactinaria EDW. and HAIME. Brit. Foss. Corals. 1850. 
Lucernariadce A<;ASS. Cont. Nat. Hist. U. S., IV. p. 175. 1862. 
Lucernaria; H. J. CLARK. Proc. Bost. Soc. Nat, Hist,, p. 47. 1862. 
Lucernarice H. J. CLARK. Journ. Bost. Soc. Nat. Hist., p. 531. 1863. 

Clark has made of the Lucernarise an order equivalent to the Hy- 
droids and the Discophorse ; but it should be remembered at the same 
time that his Acalepha3 correspond to the Hydroid and Discophorous 
Medusos of other authors, and do not include the Ctenophorae. We 
would reduce this group to the level of a suborder ; for, as Professor 
Agassiz has very justly said, the Lucernarise are only pedunculated 
Discophorse, and have no claim to be considered as a group of a higher 
value than a suborder. They seem to bear the same relation to the 
free Discophorse which the Pentacrinidse do to the Comatulidse. Their 
mode of development may show that their separation as a distinct sub- 
order is giving even too much weight to their embryonic character ; 
and we may find, with future investigations, a somewhat similar rela- 
tion between them and the Strobila, from which free Discophoras are 
produced, as that which we have between the free and sessile species 
of Tubularians. 



Family CLEISTOCARPID^l H. J. Clark. 

Clelslocarpidce H. J. CLARK. Journ. Bost. Soc. Nat. Hist,, p. 535. 1863. 

HALIMOCYATHUS H. J. CLARK. 

Halimocyathus H. J. CLARK. Journ. Bost. Soc. Nat. Hist., p. 536. 1863. 

Halimocyathus platypus H. J. CLARK. 

Halimocyathus platypus H. J. CLARK. Journ. Bost. Soc. Nat. Hist., p. 537. 

Chelsea Beach, Mass. (H. J. Clark). 

MANANIA H. J. CLARK. 

Manama H. J. CLARK. Journ. Bost. Soc. Nat. Hist., p. 541. 1863. 



62 ELEUTHEROCARPID^E. 



Manama auricula H. J. CLARK. 

Manama auricula H. J. CLARK. Journ. Bost. Soc. Nat. Hist., p. 542. 1862. 
Lucernaria auricula FAB. (won Miill.). Fauna Groenl., 1780, No. 332. 
Lucernaria typica GREENE. Nat. Hist. Rev., p. 132. 1858. 
Lucernaria Fabricii AGASS. Cont. Nat. Hist. U. S., IV. p. 176. 1862. 

I give here only the principal synonymes. For the remaining syno- 
nymes of this and other species of Lucernarias, I would refer to the 
papers of Professor Clark. 

Swampscott (Agassiz) ; Greenland (Fabricius) ; Eastport, Maine (W. 
Stimpson). 



Family ELEUTHEROOARPID^EJ H. J. Clark. 

Eleutherocarpidce, H. J. CLARK. Journ. Bost. Soc. Nat. Hist., p. 536. 1863. 

LUCERNAEIA MULL. 

Lucernaria MULL. Prod. Zool. Dan. 1776. 

Lucernaria AGASS. (y>. p.). Cont. Nat. Hist. U. S., IV. p. 175. 1862. 

Lucernaria II. J. CLARK. Journ. Bost. Soc. Nat. Hist, p. 551. 1863. 

Lucernaria quadricornis MULL. 

Lucernaria quadricornis MULL. Zool. Dan., I. p. 51, PI. 39, Figs. 1 -G. 
Lucernaria quadricornis SARS. Fauna Littor., p. 20, PI. 3, Figs. 1-7. 
Lucernaria quadricornis JOHXST. Br. Zooph., p. 252, PI. 15, Figs. 3-7. 
Lucernaria fascicularis FLEM. Wern. Soc., II. p. 248. 

Lucernaria quadricornis AGASS. Cont. Nat. Hist. U. S., IV. p. 175. 1862. 
Lucernaria quadricornis STIMPS. Mar. Inv. Grand Manan, p. 8. 1853. 
Lucernaria quadricornis II. J. CLARK. Journ. Bost. Soc. Nat. Hist., p. 551. 1863. 
Lucernaria quadricornis ED\V. & HAIME. Hist, des Cor., III. p. 459. 

Grand Manan (W. Stimpson) ; Massachusetts Bay, Chelsea Beach, 
and Swampscott (Dr. A. A. Gould and L. Agassiz) ; Greenland (Fa- 
bricius). 

Cat, No. 324, Owl's Head, Maine, W. Stimpson. 

Museum diagram No. 14, after L. Agassiz. 

HALICLYSTUS H. J. CLARK. 

"" Halicli/stus H. J. CLARK. Journ. Bost. Soc. Nat. Hist., p. 559. 1863. 



HALICLYSTUS AURICULA. 



63 



Haliclystus auricula H. J. CLARK. 

Haliclystus auricula H. J. CLARK. Journ. Bost. Soc. Nat. Hist., p. 559. 1863. 
Lucernaria auricula MULL. Zool. Dan., PI. 152. 
Lucernaria auricula MONT. Lin. Trans., IX. PI. 7, Fig. 5. 
Lucernaria auricula JOIIXST. Br. Zooph., p. 246, Second Edition. 
Lucernaria auricula SARS. Bidr. Soe. dyr., PI. 4, Fig. 1-13. 
Lucernaria octora/liata LAMK. An. s. Vert., II. p. 414. 1816. 
Lucernaria auricula EDW. & HAIME. Hist. d. Coralli, III. p. 458. 
Lucernaria auricula AGASS. Cont. Nat. Hist. U. S., IV. p. 176. 1862. 
Haliclystus auricula PACK. List of Animals. 1863. 

Without attempting a critical revision of the Lucernaria?, which has 
become necessary in consequence of the somewhat contradictory state- 
ments of Sars, Edwards, Allman, Gosse, Keferstein, and Clark, and for 
which the materials in the Museum do not afford sufficient data, I have 
adopted the generic names of Clark, as it is plain, from what was al- 
ready suggested by M. Edwards, that the Lucernaridre do not belong 
to a single genus, but that several genera can very justly be distin- 
guished upon the single genus of Lucernaria of previous authors. 

Fig. 88. Fig 89. 





The figures here introduced are of our common Lucernaria (Figs. 
88, 89), and will give a tolerable idea of the varied attitudes they 
assume. This species is quite common, found at- 
tached to eel-grass. For a further knowledge of this 
group of Acalephs, I would refer to the original 
papers quoted above. 

The young of our Lucernaria (Fig. 90) shows how 
much still remains to be done respecting the changes 
which it undergoes. In a small Lucernaria, of one 

Fig. 88. Haliclystua auricula, seen from the actinal pole. 

Fig. 89. Different attitudes of Lucernaria, of Fig. 88, attached to sea-weed, contracted, ex- 
panded, or with the. disk thrown back, and the actinostome projecting like a proboscis. These 
figures are of natural size. 

Fig. 90. Young Lucernaria, magnified, about one tenth of an inch in height, a, anchors still 
retaining the shape of the tentacles, t. 




64 HYDROIDvE. 

tenth of an inch in height, the arrangement of the tentacles is totally 
different from that of the adult. They are as yet not arranged in clus- 
ters, but placed at regular intervals in one line on the edge of the disk. 
No difference can at present be detected between the anchors (a, Fig. 
90) and the tentacles (t, Fig. 90) of the disk, showing plainly that the 
anchors, as Professor Clark has proved, are only modified tentacles ; the 
peduncle is also quite short, and stout in proportion to the disk. The 
young Lucernaria is in this state a close representative of the genus 
Carduella of Allman, which may possibly prove to be only the young 
of some European species. 

Greenland (Steenstrup) ; Anticosti (Verrill, Shaler, and Hyatt) ; 
Massachusetts Bay (H. J. Clark). 

Cat. No. 320, Naliant, Mass., A. Agassiz, May, 1862. 

Cat. No. 321, Chelsea Beach, L. Agassiz. 

Cat, No. 322, Mount Desert Islands, Maine, W. Stimpson. 

Cat. No. 323, Anticosti Island, Anticosti Expedition, August, 1861. 

Cat. No. 380, Anticosti Island, Anticosti Expedition, August, 1861. 



Haliclystus salpinx H. J. CLARK. 

Haliclystus salpinx H. J. CLARK. Journ. Bost. Soc. Nat. Hist., p. 563. 1863. 

Mount Desert Islands, Maine (Stimpson). 



ORDER HYDROID^E JOHNST. 

Anthozoa Hydroida JOHNST. Brit. Zooph., Second Edition, p. 5. 

Gymnophthalma FORBES. Brit. Naked-eyed Medusas. 1848. 

Coralliaria Tabulata, Ititf/osa, and Hydraria MILXE EDW. & HAIME. 

Hydromedusce et Siphonophorce VOGT. Siph. de Nice. 

Hydroidea, Medusida Craspedota, and Siphonophora GEGENB. Zeit. f. W. Zool. 1856. 

Hydroidts McCR. (p.p.}. Proc. Elliot Soc. 1857. 

Jf//i/rozoa HUXL. Ray Soc. 1859. 

Hydroidce AGASS. Cont. Nat. Hist. U. S., III. 1860. IV. p. 337. 

From want of materials, no writer on Acalephs has thus far attempted 
to make use of the embryological characters noticed in the development 
of young Hydroid MedusaB and of the young Hydraria. From the ob- 
servations of Wright on the development of Thawnantias inconspicua, 
of yEquorea, and from what I have had occasion to observe myself on 
the Hydroid of Melicertum and of Tima, we have acquired sufficient 
information to satisfy ourselves that Tubularian-like Hydroids stand 
lower than the Campanularians ; while such forms as the Hydroids of 



HYDROIDS. 65 

Melicertum, of Trichyra, and Lafoea, stand intermediate between them. 
Resembling the youngest stages of the Campanularian Hydrarium we 
have such forms as Clava and Rhyzogeton ; while the more branching 
forms, Eudendrium and Bougainvillia, remind us already of somewhat 
older stages. Lower still we must place Hydractinia, where the poly- 
morphism of the individuals is an evident sign of inferiority, reminding 
us of the free communities formerly separated from the Hydroids as 
Siphonophores. From the close resemblance of the animal of the 
Tabulata to such forms as Halocharis and the fresh-water Hydra, we 
must consider them as an order, or perhaps only a suborder standing in 
close relation to the Tubularians. Unsatisfactory as this may seem, 
these few facts throw much light on our knowledge of the relations of 
the Hydroids. Somewhat more satisfactory and more general results 
can be obtained by comparing the young Medusas in their various 
stages of growth. As I have already shown, in a short paper on the 
order of appearance of the tentacles of Hydroid Medusas, the young, 
when liberated, undergo great changes before arriving at their mature 
condition ; and it requires a thorough knowledge of all these changes 
to be able to recognize one and the same species in its various stages 
of growth, and not to divide, as has been done so far, different species 
by the number of tentacles, of marginal bodies, or the size of the ova- 
ries. The main characteristic of the greater number of Tubularians, 
when first liberated, is the totally different shape of the bell from that 
of the adult. The bell is very deep, the number of tentacles is small 
(Turritopsis, Bougainvillia, and Nemopsis) ; in the adult the shape of the 
bell has become quite globular, the tentacles have increased in number, 
the ovaries, which are generally absent or but slightly developed in the 
young Medusas, have taken a development corresponding to their age. 
Applying this to the standing of the different Tubularians, we should place 
genera such as Clava and Eudendrium, in which the Medusas are always 
sessile, lowest in their families ; next, the old genus Tubularia, such as 
Tubularia proper, next Corymorpha, Hybocodon, then Ectopleura, where 
we find the Medusa) losing almost entirely their embryonic character. 
From these we pass to Sarsia, Syndictyon, Dipurena, Saphenia, Turns, 
and Turritopsis. We then have families where the localization of the ten- 
tacles, the position of the ovaries along the proboscis, and partly along 
the chymiferous tubes, is a character of superiority, such as Dysmorphosa, 
Lizzia, Bougainvillia, and Nemopsis, having a limited number of tentacles 
placed at stated points along the circular tube. Closely allied to these 
are such more Campanularian-like forms, as Melicertum, Ptychogenia, 
and Staurophora, where the number of tentacles is large, but which 
want the peculiar marginal bodies so characteristic of Campanularian 
Medusas, and where the genital organs are intimately connected with 
the digestive cavity. The young of these Medusas (Melicertum and 

NO. II. 9 



66 HYDROIDJE. 

Staurophora) have, like the young Tubularian Medusas, a deep bell and 
few tentacles ; these characters they lose with advancing age. The 
young Medusas of the greater part of the Campanularian Hydroids, 
with the exception of the Eucopidae and some of the vEquoridas, also 
have, immediately after they are liberated, a form totally unlike that 
which they eventually assume. A young Clytia or Oceania has a deep 
bell, only a couple of long tentacles, and few marginal capsules, having 
a totally different arrangement from what we find in the adult. With 
advancing age, the tentacles and marginal bodies increase in number, 
the disk becomes flattened, and ovaries make their appearance alono- 
the chymiferous tubes. In the Eucopidas the number of tentacles with 
which the young Medusas are liberated is far greater, the marginal cap- 
sules being constant in young and old. The same is the case with the 
^Equoridas ; they are liberated with many tentacles, and the disk, like 
that of the Eucopidae, is quite flat. We find also among the Campanu- 
larians, in some genera, a tendency to localization of the tentacles, as in 
Eucheilota ; or to great complexity of the marginal capsules, as in Tima 
and Tiaropsis ; and finally a great development of the gelatinous pro- 
boscis, as in Eutima, Geryonia, and Tima. The gelatinous prolongation 
of the disk we must regard as an embryonic feature ; the great number 
of chymiferous tubes is likewise a character of inferiority ; so that we 
would place lowest among the Campanularians the Geryonopsidas, all 
these having tolerably deep bells and few tentacles, more resembling the 
Tubularians ; next the ^Equoridas, some of which, in their young stages 
(Halopsis), resemble the Medusas of Tubularians, with their high bell and 
few tentacles ; next would come the Eucopidas, having still a large num- 
ber of tentacles, but where the marginal capsules are limited in number, 
and in which the young Medusas at no time resemble the young Me- 
dusas of Tubularians ; finally, highest of all the Campanularians would 
stand the Oceanidas, where the number of tentacles is not very great, and 
the complication as well as localization of the marginal capsules is very 
definite. The ovaries likewise guide us somewhat in this classification ; 
they extend along the proboscis and chymiferous tubes in Tima and 
the Geryonopsidas ; in the ^quoridas they take their origin from the 
base of the digestive cavity ; in the Eucopidas they are limited, as well 
as in the Oceanidas, to definite parts of the chymiferous tubes. 

Were we to judge simply from the nature of the Medusas of the so- 
called Siphonophoras, the swimming bells and the sexual Medusas, we 
should be justified in uniting them with the same order as Hydroids, 
making, of the different orders which had been proposed before, only 
suborders of the great order of Hydroids, and thus not recognizing the 
class of Siphonophoras, as recently modified by some naturalists. There 
is perhaps no stronger case to be brought up in confirmation of this 
view, than the fact that the free Medusas of Yelella are so closely allied 



HYDROIDyE. G7 

to the Medusae of some of our Tubularians, that McCrady even proposed 
to separate the Velellidoe from the Siphonophorse, and to place them 
next the Tubularians ; the sexual Medusae, also, of several of these free 
Hydroids resemble very closely other Medusa?, as those of Hybocodon, 
Corymorpha, and the like. When we add to this the strong argument 
derived from the homology of the development of the Hydroids, whether 
free or floating, as is shown hereafter from Nanomia, we can have but 
little hesitation in acknowledging the value of the order of Hydroids as 
first limited by Professor Agassiz, and the return, as proposed by him, 
to the old subdivisions of Eschscholtz, the great master in the classifica- 
tion of the Acalepha?, whose views seem to stand out brighter with 
every fresh investigation. For certainly the subdivision by Leuckart 
of the Siphonophorae into two suborders, and the uniting of Physalia 
and Porpita and the like into one order with Agalma and its allies, is a 
disregard of the true value of the ordinal characters which are to be 
found in the combination of the float with the rest of the community, 
such as we find developed in the three great phases of embryonic 
growth of a Physophore. (See Nanomia.) As to the true position of 
the different orders of the old group of Siphonophorae among the 
Hydroids, we cannot fail to consider them as lowest in the series ; they 
form communities, the different individuals of which never attain the 
high degree of complication and the individuality so characteristic of 
the Campanularian Medusae, and they must therefore rank lowest, next 
to Hydractinia and the like, which form the connecting link between 
them and the truly fixed Hydroids. 

In the limitation of the families of Hydroids, it is very difficult to 
draw any line of demarcation, whenever we attempt to separate, as dis- 
tinct families, those Medusae which are always sessile, from those which 
lead an independent existence. The close affinity existing between the 
Hydroids of genera in which we have free and sessile Medusae, seems to 
preclude the idea of separating them as distinct families, notwithstand- 
ing the great difference of form between the adult Medusae. As our 
knowledge of the embryology of Hydroids becomes more extended, 
cases occur more frequently in which Hydroids, so closely allied that it 
is difficult to distinguish them generically, unless it be in the breeding 
season, produce Medusae which are either sessile, or lead an independent 
existence ; for instance, the many species of Campanularians closely allied 
to Laomedea, the Tubularians of the genus Tubularia, and the different 
species formerly referred to Eudendrium. We must combine, as far as 
we are able from existing information, our knowledge of the Medusa and 
of the Hydrarium ; this seems the only rational method, and one which 
has already lead those who have adopted it to very important relations 
of the true affinities of Acalephae. This view of the proper method to 
be followed in the classification of Hydroids has been frequently em- 



68 SERTULARIJE. 

ployed by Agassiz, Leuckart, and Vogt. Sars, in his paper on Cory- 
morpha, has developed it fully, quoting many instances in support of 
this theory. Allman, in a recent paper on the Classification of Hy- 
droids, has carried the same method out for the Tubularians. 



SUBORDER SERTULARI^E AGASS. 

Sertularice AGASS. Cont, Nat. Hist. U. S., IV. p. 348. 1862. 
Sertularina EIIRENB. Corall. des roth. Meeres. 
Sertularina JOILXST. Brit. Zooph., p. 56. 



Family OCEANID^E Esch. (rest. Ac,). 

Oceanidce ESCH. Syst. d. Acal., p. 96. 1829. 

Eucopiche GEGENB. (p.p.}. Versuch eines Syst. d. Mod., p. 241. 1856. 

Oceanidce AGASS. Cont. Nat. Hist. U. S., IV. p. 352. 18G2. 

The free Medusae which belong to this family are characterized in 
their adult condition by the flatness of the bell, and its thinness, long, 
hollow tentacles, not very numerous, four chymiferous tubes, marginal 
capsules, and a short proboscis. The Hydrarium is remarkable for its 
ringed or pedunculated reproductive calycles. 

The genus Thaumantias, until the time of Forbes, contained in it 
Medusae belonging to several genera. Forbes first proposed to divide 
it, and suggested the name Cosmetira for his Thaumantias pilosella. 
Gegenbaur, in 1856, proposed another name, that of Eucope, which in- 
cluded several species of the genus Thaumantias, belonging to a dif- 
ferent family, the EucopidiB. 

As long as the numerous species of Thaumantias, described by Forbes, 
have not been investigated again with special reference to the marginal 
capsules, it is impossible to assign many of them their true position in 
the genera Eucope, Oceania, and Laodicea, which have been distin- 
guished in these Acalephs. It seems to me doubtful whether the genus 
Epenthesis of McCrady can be retained, and I think it will eventually 
prove identical with Oceania, if we limit the genus to such species as 
Thaumantias liemisplmrica of Forbes. The Hydra of Oceania is a 
Wrightia ; that of the Eucope diaphana ,of our coast is a Laomedea, 
resembling the L. geniculata of England, The genus Eucope of Gegen- 
baur would be limited to those species which have small ovaries, occu- 
pying but a short space of the chymiferous tubes ; and instead of 
having the long, thin, and exceedingly contractile tentacles of Oceania, 
have short, stout, knotty tentacles, which are carried straight from the 
edge of the disk, are hardly contractile, and have a prolongation inside 
of the circular tube. 



TIAROPSIS. 



69 



TIAROPSIS AGASS. 

Tiaropsis AGASS. Mem. Am. Acad., IV. p. 289. 1849. 
Tiaropsis AGASS. Cont. Nat. Hist. U. S., IV. p. 355. 18G2. 



Tiaropsis diademata AGASS. 

Tiaropxh dlcidi-mnta AGASS. Mom. Am. Acad., IV. p. 289, PI. 6. 

Tiuropxix did< nutta AGASS. Cont. Nat. Hist. U. S., III. p. 354, PI. 31, Figs. 9-15; IV. pp. 308 

-311, Figs. 45-48. 18C2. 

T/C//-O/J.V/.S- diiidcmitta A. AGASS. Proc. Bust. Soc. Nat. Hist., IX. p. 93, Fig. 10. 
Tiuropsig diademata MORCII. ; in Beskriv. af Groenland. 1857. 



This Medusa is one of the earliest visitants of our wharves in the 
spring. In company with Sarsia and Syndictyon, it occurs in great 
numbers during the spring months ; it attains its full size in a com- 
paratively short period (Fig. 91), spawns during April and May, and 
after that it is found but rarely, disappearing totally during the sum- 
mer. Although so common, the Hydroid of this Medusa has not been 
observed. Young Medusae (Fig. 92), which are fully described in Pro- 



rig. 91. 



Fiz. 93. 




Fig. 92 





fessor Agassiz's Contributions, are exceedingly numerous. The tentacles 
develop independently of the eyes, while the latter never increase in 
number. (See Fig. 93.) For a more detailed description of their mode 
of growth, see also my paper on the marginal tentacles of Hydroids. 

The Thaumantias Pattersonii of Greene seems to me, as far as I can 
make out from his description and figures, to belong to the genus Tia- 
ropsis. There must be some error in his view from above, in which he 
represents black ocelli at the base of the chymiferous tubes ; I doubt if 

Fig. 91. Tiaropsis diademata, natural size. 

Fig. 92. Young Tiaropsis, having twenty -four tentacles. 

Fig. 93. Young Tiaropsis, having forty tentacles, c, eye-speck ; /, digestive cavity ; g, chy- 
miferous tube; e, primary tentacles ; a, middle tentacle; b, third set of tentacles in pairs; , fourth 
and fifth sets of pairs of tentacles. 



fO OCEANIA. 

this is really the case, as we have nothing of the sort among any of the 
other Hydroid Medusae. 

Massachusetts Bay (Agassiz). 

Cat. No. 266, Boston, April, 1862, A. Agassiz. Medusa. 

Cat. No. 267, Boston, May, 1862, A. Agassiz. Medusa. 

Cat. No. 358, Boston, May, 1862, H. J. Clark. Medusa, 



OCEANIA PER. et LES. 

Oceania PER. et LES. Ann. du Mus., XIV. p. 32. 1809. 

Tlianmantin* Escii. Syst. d. Acal., p. 79. 1829. 

Oceania LESS. Zooph. Acal., p. 318. 1843. 

Phiallilium LEUCK. Arch. f. Nat., I. 1856. 

Epenthesis McCR. Gymn. Charl. Harb., p. 89. 

Oceania AGASS. Cont. Nat, Hist. U. S., IV. p. 352. 1862. 

Wrightia AGASS. Cont. Nat. Hist. U. S., IV. p. 354. 1862. Hydrarium. 



Oceania folleata AGASS. 

Oceania folleata AGASS. Cont. Nat. Hist. U. S., IV. p. 353. 1862. 
Epenthesis folleata McCu. Gymn. Charl. Harb., p. 89. 

Charleston Harbor (McCrady). 



Oceania languida A. AGASS. 

Oceania languida A. AGASS.; in Agassiz's Cont. Nat. Hist. U. S., IV. p. 353. 1862. 
Hydrarium. The American species of Wrightia mentioned in a note by Professor Agassiz, in 

Cont. Nat, Hist. U. S., IV. p. 354. 1862. 
? Campanularia syriuga STIMPS. Mar. Inv. Grand Manan, p. 8. 1853. 

It must remain doubtful whether this species is not the Epenthesis 
folleata McCr. found in Charleston Harbor. McCrady observed only a 
single specimen, and his description is too short not to leave some doubt 

on this point. His single specimen, moreover, was 
not in a normal condition, as he says there w r ere 
five labial appendages. From the fact that there 
is but one marginal capsule between each tentacle 
in the Charleston species, and rarely two, while 
there are always two, and frequently three, in the 
specimens taken on our coast, I would infer that 
they are distinct species. 

The capsules are small, and contain only one 
large granule. The bulbs at the base of the ten- 
tacles (6, Fig. 94) are large swellings, colored with dark pigment-cells ; 
the tentacles are thread-like, very extensible, with lasso-cells scattered 

Fig. 94. Two marginal tentacles, with a portion of the circular tube, f, one of the marginal 
capsules in process of division ; b, sensitive bulb of tentacle. 





OCEANIA LANGUIDA. 

irregularly all over the surface ; the walls of the tentacles are thin, 
leaving a wide tube running to their extremity ; the labial folds of the 
short digestive cavity are simple, the edges not being fringed (/, Fig. 
95) ; the bell is perfectly transparent and ex- 
ceedingly thin, remaining of the same thick- 
ness close to the edge ; the veil is of medium 
size. The ovaries and the base of the diges- 
tive cavity are light brown ; the base of the 
tentacles is somewhat darker. The number of 
tentacles is from thirty-two to forty ; the Me- 
dusa measures from three fourths to seven 
eighths of an inch in size. The marginal cap- 
sules are formed by division, a small portion 
of the capsule being separated by a constriction, and a granule devel- 
oped in it (c, Fig. 94) forms the new capsule, which gradually becomes 
more and more distinct in older specimens. 

The observations of Wright on Laomedea acuminata, combined with 
the development given here of a Medusa (Fig. 96) similar to the one 
he observed, give us the complete history of the genus Oceania. It is 
particularly important on account of the light it throws on the probable 
identity of many of the species described by Forbes under the name of 
Thaumantias, and which are distinguished by the greater or smaller 
number of tentacles, and the position and size of the ovaries. Differ- 
ences, similar to those by which he has distinguished such a large 
number of species, are readily traced in the different stages of our 
Oceania. Professor Agassiz had separated the Hydroid figured by 
Wright, as a distinct genus, from Clytia, on account of the peculiar 
position of the marginal capsules, totally different from what is observed 
in that genus. The development of the Medusa shows this to be a 
correct appreciation of the differences noticed in the young ; but as the 
genus of the adult Medusa is one already well known, Wrightia, the 
name given to the Hydrarium by Professor Agassiz, must be rejected. 
We have on our coast two species of Wrightia?, one of which produces 
planula?, and resembles, in its general appearance and mode of branch- 
ing, the Laomedea acuminata figured by Wright in the Edinburgh New 
Philosophical Journal for 1856 ; the latter, however, produces Medusae, 
while the second species is closely allied to the European Campanularia 
syringa ; it has reproductive calycles similar to the calycles of the 
Campanularia fastigiata Alder ; it differs considerably from the figure 
of the C. syringa given by Van Beneden, the stolon of our species 
being as strongly ringed as the pedicel ; the calycle is likewise slightly 
constricted in the middle. This species has not been found with 

Fig. 95. Magnified view of the actinostome. T, chymiferous tube ; /, one of the four simple 
lobes of the actinostome. 



72 OCEANIA LANGUIDA. 

reproductive calycles in March, April, or September ; I am therefore 
unable to state whether it is the Hydrarium of our common Oce- 
ania. 

A very young Oceania (Fig. 96), soon after its escape from the 
reproductive calycle, has a very deep bell (Fig. 96), two long tentacles 
and two rudimentary ones at the base of the chymiferous tubes. It 
resembles in its general appearance and motion the Medusa of Clytia 
bicoiihora ; the bell is covered with large lasso cells, scattered irregu- 
larly over the surface ; it can at once be distinguished from the latter 

Fig. 97. t ' 

^aatflHtt 

Fig. 96. Fig. 98. 






Medusa by the absence of ovaries, the two long tentacles (/, Fig. 97), 
and by what characterizes at once this genus, the position of the mar- 
ginal capsules (c, Fig. 97) on each side of the primary tentacles (t, t', 
Fig. 97), at the base of the chymiferous tubes, while in Clytia they are 
placed on each side of the secondary rudimentary tentacle, half-way be- 
tween the chymiferous tubes. The young Medusa, in more advanced 
Fig 99 stages, has become quite conical (Fig. 98), 

the ovaries are forming, and, besides the two 
original long tentacles, we have the two ru- 
dimentary primary tentacles fully formed, as 
well as eight others half-way between the 
chymiferous tubes, and rudiments of eight 

c/ O 

additional tentacles half-way between these 
and the chymiferous tubes. The proboscis 
has likewise somewhat lengthened. In still 
older specimens, in which the fourth set of 
rudimentary tentacles has developed ( 4 , Fig. 
99), and in which we can trace the position of 
the remaining sixteen tentacles (t", Fig. 99), 
the ovaries have also taken a greater development, and are now ellipti- 

Fig. 96. Young Medusa of Oceania languida, immediately after escaping from the reproduc- 
tive calycle. 

Fig. 97. The same, seen from the actinal pole, to show the position of the marginal capsules, 
r, on the sides of the tentacles, t, C. 

Fig. 98. Somewhat more advanced Medusa, in which traces of the ovaries can be detected. 

Fig. 99. Quarter of the disk of a still more advanced Oceania, where the remaining tentacles 
of the adult (/") are developing between the tentacles, t 1 , t\ t 3 , t\ t, as well as additional marginal 
capsules, c. 




OCEANIA LANGUIDA. 



Fig. 100. 




Fig. 101. 




cal pouches, occupying about one fifth of the length of the chymiferous 
tubes. With advancing age the bell of the Oceania grows more and 
more flattened, until, in the adult (Fig. 100), 
it has assumed the shape of a flat segment of 
a sphere. New marginal capsules are devel- 
oped at the same time with the rudimentary 
tentacles, one between every two tentacles 
in the younger stages ; afterwards there are 
from two to three capsules between the ten- 
tacles in the adult. The genital organs of 
the adult Medusa occupy more than two 
thirds the length of the chymiferous tubes ; 
when distended with eggs, as in Fig. 101, 
they hang in irregular lobes from the point 

of attachment, a ; the eggs are quite large ; there is no difference in 

the shape of the male and female genital 
organs, those of the males are simply some- 
what darker brownish-colored than the ova- 
ries. These Medusa? are among the most 
common on our shores ; they attain their 
full size during September, when they are 
frequently met in immense shoals on warm, 
still, sunny days, collected together for spawning. The young (Fig. 96) 
make their appearance as early as the end of May. The adult Medusa? 
assume the most extraordinary attitudes as they float along, carried 
about by the current ; the disk is so Fig . 10 2. 

extremely flexible that at times it 
seems almost as if the Medusa had 
rolled itself up, as in Figure 102, 
the tentacles being the strings by 
which the two edges have become fas- 
tened together. They are exceedingly 
lazy in all their movements, hard- 
ly contracting their tentacles when 
disturbed, contrasting strangely with their former activity in younger 
stages (Fig. 96), when they move through the water with short, 
rapid jerks, stopping only to take a more vigorous start. The 
young Medusa? of Campanularians are all very active, whatever may 
be the habits of the adults, while in the Tubularians we have gen- 
erally in the young Medusa? the temperament of the adult. Young 
Medusa? of Bougainvillia, Lizzia, and Zanclea are lazy, like the adult ; 

Fig. 100. Adult Oceania languida, natural size. 

Fig. 101. Magnified view of an ovary. , abactinal part of the genital organ. 

Fig. 102. Peculiar attitude sometimes assumed by these Medusae. 
NO. II. 10 





74 EUCHEILOTA. 

while Sarsia, Nemopsis, and Margelis are as active when young as 
when full grown. 

Eastport, Maine (L. Agassiz) ; Massachusetts Bay (A. Agassiz) ; Buz- 
zard's Bay (A. Agassiz). 

Cat. No. 280, Naushon, A. Agassiz, September, 1861. Medusa. 

Cat. No. 450, Nahant, A. Agassiz, June, 1864. Medusa. 



Oceania gregaria A. AGASS. 

Oceania gregaria A. AGASS. ; in Agassiz's Cont. Nat. Hist. U. S., IV. p. 353. 1862. 

This Medusa is somewhat smaller than its Eastern representative. 

It differs from it strikingly by the great length of the slender lips 

Fig . 103 . of the actinostome (Fig. 103) ; the color of 

the genital organs and of the sensitive bulb 
of the tentacles is a beautiful pale yellow, 
in strong contrast to the dark coloring of 
our species ; the marginal tentacles are only 
moderately contractile. The whole surface 
of the water for several miles was often thickly covered with these 
Medusas. Found in the Gulf of Georgia, from June to October. 
Gulf of Georgia, W. T. (A. Agassiz). 
Cat. No. 124, Gulf of Georgia, W. T., June, 1859, A. Agassiz. Medusa. 

EUCHEILOTA McCR. 

Eucheilota McCii. Gymn. Cliarl. Harb., p. 84. 

Eucheilota AGASS. Cont. Nat. Hist. U. S., IV. p. 353. 1862. 

Eucheilota ventricularis McCR. 

Eucheilota ventricularis McCR. Gymn. Charl. Harbor, p. 85, PI. 11, Figs. 1-3; PI. 1, Figs. 1, 2. 
Eucheilota ventricularis AGASS. Cont. Nat. Hist. U. S., IV. p. 353. 18fi'2. 
Eucheilota ventricularis A. AGASS. Proc. Bost. Soc. Nat. Hist., IX. Figs. 16, 17. 

rig. 104. The small Medusa represented in Fig. 104 is exceedingly 

common at Naushon, and I suppose it to be a young of this 
species, though I did not trace its development long enough 
to satisfy myself fully on this point. It has the characters 
of the genus as given by McCrady, with the exception of 
the ovaries, which were not yet developed in the oldest 
specimens observed. Young specimens, of a sixteenth of an 
inch in diameter, have four tentacles, one opposite each of 
the chymiferous tubes, of the length of the diameter of the 

Fig. 103. One of the four lips of the actinostome of Oceania gregaria. 
Fig. 104. Young of Eucheilota veutricularis McCr. 





EUCHEILOTA DUODECIMALS. 75 

bell, with tentacular cirri well developed ; two marginal capsules be- 
tween each tentacle, and rudiments of four additional tentacles half- 
way between the capsules. (Fig. lOo.) These tentacles have at first no 
lateral cirri ; it is only when they have assumed the shape of the lower 
basal part of a full-grown tentacle that the cirri appear like two round 
knobs, which are rapidly developed into lateral cirri before the lash of 
the tentacle has been formed. The form of the young Medusa, with 
only four tentacles, is globular, but it soon becomes flattened as it ad- 
vances in growth. The digestive cavity is a simple long Fig.ios. 
tube, hanging stiffly in the interior of the bell, which has 
a very small circular opening ; the chymiferous tubes are 
wide ; the basal swelling of the tentacle is large and coni- 
cal, narrowing very rapidly into the thread of the tentacle 
itself, which is exceedingly slender, with thin walls, and 
lasso cells scattered irregularly over its surface. The 
marginal capsules contain only one granule, while Mc- 
Crady's species contains three or four. This may prove to be the 
specific difference between these young specimens and the Charleston 
species, as I have not, even in those specimens which had already eight 
tentacles, found more than one granule, except in a single case two, in 
one of the capsules. 

Charleston, S. C. (McCrady) ; Buzzard's Bay, Naushon (A. Agassiz). 



Eucheilota duodecimalis A. AGASS. 

Euclieilota duodecimalis A. AGASS. ; in Agassiz's Cont. Nat. Hist. U. S., IV. p. 353. 1862. 

This species differs from the above in having twelve marginal cap- 
sules, one on each side of the four large tentacles (c, Fig. 107), and one 
in the middle of the circular tube (Fig. 106) ; there are four long ten- 
tacles, with lateral cirri (t f , Fig. 107) Fig.ioe. 
and long slender lashes, which are 
covered with lasso cells ; the chymif- 
erous tubes are wide, and from their 
point of junction with the circular tube 
arise ribbon-shaped genital organs (o, 
Fig. 107), which do not extend more 
than one third of the length of the 
chymiferous tube (Fig. 106) ; the 
disk is of very uniform thickness, the 
inner and outer surface of the bell being almost concentric to the very 

Fig. 105. More magnified view of a quarter of the disk, to show the position of the capsules 
and tentacular cirri. 2, the second set of tentacles in Figs. 104, 105. 
Fig. 106. Eucheilota duodecimalis A. Agass. ; greatly magnified. 




76 



EUCHEILOTA DUODECIMALS. 




Fig. 107. edge ; in the cavity hangs a short urn-shaped digestive sac, 
attached to the four chymiferous tubes by a circular base, 
and not quadrangular, as in the E. ventricularis ; there is 
only a single granule in each of the marginal capsules. 
This species seems to be full grown, as the sexual glands 
were very much distended with spermaries, and I could 
not see any traces of additional tentacles ; however, as 
the presence of eggs and spermaries is far from being a 
criterion of maturity among these animals, we must have 
further materials to decide this point. Only three speci- 
mens of this species were found, a very young female, 
the male here figured, and an older female (Fig. 107 a ), in 
which the ovaries were filled with apparently mature eggs, 
the genital pouches extending from the base of the chymif- 
erous tubes to the base of the proboscis ; the thickness of the 
bell and its shape is totally different from that of the male, if it belongs 
to the same species ; the bell is of uniform thickness, quite squarish 
in outline ; the trace of the connection with the Hydrarium is still 
very distinct, and the tentacles are carried in the erect manner so 
characteristic of young Hydroid Medusae, showing that, in spite of its 
weU-developed ovaries, it must have but recently been liberated from its 

Hydrarium. The character of the differ- 
ence between the young of these two spe- 
cies of Eucheilota makes it highly probable 
that the E. duodecimalis may form, when 
its adult is known, the basis for a separate 
genus ; we find in the arrangement of the 
capsules differences similar in character to 
those observed between the young of Oce- 
ania and of Clytia, the adult Medusae of which are generically distinct, 
I cannot help surmising that we shall find differences of a like nature 
when the adult of E. duodecimalis becomes known. This is the more 
probable now that we know the young of E. ventricular is , the adult 
of which has so much the general appearance of an Oceania. 
Buzzard's Bay, Naushon (A. Agassiz). 
Cat. No. 453, Naushon, July, 1864, A. Agassiz. Medusa. 

Fig. 107. Junction of one of the chymiferous tubes with the circular tube. 0, spermary ; c, 
marginal capsule ; t, one of the four primary tentacles ; t', tentacular cirri. 
Fig. 107 a . Female Medusa of Eucheilota duodecimalis ; greatly magnified. 



Fix. 107". 




CLYTJA. 77 



CLYTIA LAMX. 

Clytla LAMX. Bull. Soc. Phil. 

Chjtia AGASS. Cont. Nat. Hist. U. S., IV. pp. 297, 354. 1862. 

Calicclla HIXCKS. 

TrocTtopyxis AGASS. Cont. Nat. Hist. U. S., IV. pp. 297, 354. 1862. 

IPlatypyxis AGASS. Cont. Nat. Hist. U. S., IV. pp 306, 354. 1862. 

The adult Medusa of Platypyxls cylindrical of Professor Agassiz is 
not known ; he has separated this genus from Clytia from the character 
of the reproductive calycles only. The young Medusae are very much 
alike, and we mav have a case here, the reverse of what we find in 

t/ 

Sarsia and Syndictyon, of Medusae very similar in their younger stages, 
but totally different in the adult forms. 



Clytia intermedia AGASS. 

Clytia intermedia AGASS. Cont. Nat. Hist. U. S., IV. p. 305, PI. 29, Figs. 10, 11. 1862. 

Cat. No. 143, Nahant, Mass., April, 1855, H. J. Clark. Hydrarium. 



Clytia volubilis A. AGASS. 

Campanularia volubilis A.LDER (iion Auct). Cat. Zooph. Nortkuinb. and Durham, p. 35. 

Alder was the first to distinguish the several species which have 
been confounded under the name C. volubilis by different authors. 
Specimens in no way to be distinguished from the European C. volu- 
bilis have been found on our coast with their reproductive calycles, 
seeming to leave little doubt that the specimens here catalogued 
belong to this species. 

Massachusetts Bay (L. Agassiz) ; Cape Cod (L. Agassiz). 

Cat. No. 145, Norway, Sars. Hydromedusarium. 

Cat. No. 146, Cape Cod, June, 1857, Captain N. E. Atwood. Hydro- 
medusarium. 

Cat, No. 432, Sea Coal Bay, N. S., 1861, Anticosti Expedition. Hy- 
dromedusarium. 

Cat. No. 435, Mingan Islands, 1861, Anticosti Expedition. Hydro- 
medusarium. 



78 



CLYTIA BICOPHORA. 



Fig. 108. 




Clytia bicophora AGASS. 

Clytia bicopJiora AGASS. Cont. Nat. Hist. U. S., IV. pp. 304, 354, PL 27, Figs. 8, 9 (as C. cylin- 

drica) ; PL 29, Figs. 6-9. 1862. 

Clytia bicophora A. AGASS. Proc. Boston Soc. Nat. Hist., IX. Figs. 14, 15. 
Clytia cylindrica AGASS. (p.p.). Cont. Nat. Hist. U. S., IV. Fig. 14. 1862. 

Under the name of Eucope campanulata, Eucope Thaumantoides, and 
EuQOpe affinis., Gegenbaur lias described three species, which, to judge 
from the development of a similar Medusa of our coast, Clytia 'bicoph- 
ora, are probably only different ages of the same species. 
The difference in shape of the ovaries in the different 
stages of the males and females, as seen in our Oceania, 
may account for the difference of form which Gegenbaur 
has found in the genital glands : I have been able to 
observe the same differences in our Clytia. The differ- 
ence in the shape of the bell of his species is similar to 
what we find at different periods in our Clytia. When 
hatched from the calycle, the bell is globular (Fig. 108) ; 
the digestive cavity is a simple cylinder ; the ovaries are 
hardly visible, as very short narrow lines on both sides 
of part of the upper half of the radiating tubes ; there are only four 
tentacles. As it grows older, the actinal portion of the bell bulges out ; 
the second set of tentacles, which were small bulbs, have now grown 
out, and there are traces of eight other tenta- 
cles (Fig. 109); the ovaries are also larger. At 
this stage the bell has the shape of a segment of 
a sphere, and has entirely lost its globular out- 
line, the marginal capsules have not increased 
in number, there are only two between each 
radiating tube, just as we have them in the young Medusa at the time 
when they are freed from the reproductive calycle. In the next stage 
of the Medusa the rudimentary tentacles of Fig. 109 have developed 

into long flexible lashes, usually carried curled 
up, as in Fig. 110. In the adult of this Medusa 
there are no traces of any additional tentacles ; 
though not measuring more than a quarter 
of an inch in diameter, yet they are very con- 
spicuous on account of the accumulations of 
black pigment-cells in the bulb of the tentacles ; 
two additional marginal capsules have also been formed, one on each 
side of the four primary tentacles ; the ovaries are brownish purse-like 

Fig. 108. Clytia bicophora, immediately after its escape from the reproductive calycle. 

Fig. 109. A somewhat older Clytia bicophora. 

Fig. 110. An adult Clytia bicophora, measuring one quarter of an inch. 



Fig. 109. 




Fig. 110. 




CLYTIA BICOPIIORA. 79 

glands, extending towards the base of the proboscis. The Hydrarium 
(see figure of Professor Agassiz in Vol. IV. PI. 29, Fig. 6) grows from 
three quarters to an inch in height, in small tufts attached to Fucus ; the 
calycles are strongly compressed (Fig. Ill), and differ as much in their 
proportions as those of G. cylindrica, when seen from the broad or from 
the narrow side. This species may yet prove identical with the Clytia 
Johnstoni of Alder. According to the figure of Wright of the Medusa 
of Campanularia Johnstoni, it can hardly be distinguished from the 
Medusa of our Clytia bicophora ; the Medusa of C. vohtbiUs figured by 
Hincks resembles also closely our Clytia Medusa?. The Medusa figured 
by Dalyell as the young of M. fimbriata, on PI. 
52, Fig. 4, Rare and Remarkable Animals of 
Scotland, is undoubtedly a young Medusa of C. 
Johnstoni, to judge from its characteristic attitude. 
If the figure which Gosse has given of the calycle 
of this same species in his " Devonshire " is correct, 
there can be but little question as to their specific 
difference ; the peculiar species figured by Gosse 
has, however, not been noticed by other English 
observers. The Medusae of Clytia cylindrica and ' 
of Clytia bicophora are so alike, immediately after 
their escape from the reproductive calycles, that 
when the development of Clytia cylindrica was first discovered, the 
Medusae which are here figured as Clytia bicophora (Fig. 41, Agassiz's 
Cont. Nat. Hist,, p. 307) were mistaken for the adult of the Medusae of 
Clytia cylindrica. As the Clytia bicophora is very common at Nahant, 
the complete development of the Medusa has been traced, and the 
error is here corrected. 

Eastport, Maine (W. Stimpson) Massachusetts Bay (Agassiz) ; Vine- 
yard Sound and Naushon (L. and A. Agassiz). 

Cat. No. 133, Eastport, Maine, July, 1852, W. Stimpson. Hydrome- 
dusarium. 

Cat. No. 134, Beverly, Mass., July, 1861, A. Agassiz. Hydrarium. 

Cat, No. 135, Vineyard Sound, July, 1849, L. Agassiz. Hydromedu- 
sarium. 

Cat, No. 136, Grand Manan, August, 1857, J. E. Mills. Hydromedu- 
sarium. 

Cat, No. 137, Nahant, Dec, 1855, H. J. Clark. Hydromedusarium. 

Cat, No. 154, Eastport, Maine, July, 1852, W. Stimpson. 

Cat, No. 401, Nahant, June, 1862, A. Agassiz. Hydromedusarium. 

Cat. No. 443, Nahant, June, 1864, A. Agassiz. Medusa. 

Museum diagram No. 17, after L. and A. Agassiz. 

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




80 



PLATYPYXJS. 



PLATYPYXIS AGASS. 

Platypyxis AGASS. Cont. Nat. Hist. U. S., IV. pp. 306, 354. 1862. 



Platypyxis cylindrica AGASS. 

Clytia (Platypyxis) cylindrica AGASS. Cont. Nat. Hist. U. S., IV. pp. 306, 354 (non PL 27, Figs. 

8, 9) ; p. 307, Figs. 42-44 (non Fig. 41). 1862. 

Campanula-rio, volulrilis LEIDY. Mar. Inv. Faun. N. Y. and R. I., p. 6. 1855. 
Campanularia noliformis McCn. Gynin. Charl. Harb., p. 92, PL 11, Fig. 4. ? 

The reproductive calycle is conical, smooth, strongly compressed in 
one direction, with a slight constriction near the free end, which flares 
outwards (Fig. 112) ; there are from three to four young Medusae 
developing simultaneously, though only one seems to escape at a 
time, and not several in close succession, as is the case with Laomedea ; 
the Medusa nearest the upper extremity occupies more than half of 
the whole space ; there is nothing here like the corrugations which 



Fig. 112. 




Fig. 113. 




Gosse has figured in his C. voluMHs, or of the spur which projects 
beyond the point of attachment of the calycle ; when seen edgeways, 
the calycle is strongly bent at the base (Fig. 113), and the upper edges 
do not flare out, as when seen from the broad side. The Hydrarium 
(Fig. 114) is found in shady places, near low-water-mark, and imme- 
diately beyond it ; largest specimens about an eighth of an inch in 
height. 

Charleston, S. C. (McCrady) ; Point Judith (Leidy) ; Massachusetts 
Bay, Nahant (L. Agassiz) ; Buzzard's Bay, Naushon (A. Agassiz). 

Cat. No. 141, Naushon, Sept. 1861, A. Agassiz. Hydromedusarium. 

Cat. No. 142, Nahant, Mass., Sept. 1854, H. J. Clark. Hydrarium. 

Fig. 112. Reproductive calycle of P. cylindrica, seen from the broad side. 
Fig. 113. The same, seen from the narrow side. 
Fig. 114. Sterile Hydra of P. cylindrica. 



EUCOPID^E. 81 



ORTHOPYXIS AGASS. 

OrtJiopyxis AGASS. Cont. Nat. Hist. U. S., IV. pp. 297, 355. 1862. 
Clytia LAMX (p.p.). Bull. Soc. Phil. 1812. 
? Silicularia MEYEX. Nov. Act., XVI. 1834. 



Orthopyxis poterium AGASS. 

OrtJiopyxis poterium AGASS. Cont. Nat. Hist. U. S., IV. pp. 297, 302, Fig. 40; p. 355; Pis. 28, 29, 
Figs. 1-5. 1862. 

Massachusetts Bay (Agassiz) ; Nova Scotia (Anticosti Expedition). 
Cat. No. 125, Nahant, April, 1856, H. J. Clark. Hydromedusarium. 
Cat. No. 126, Naliant, June, 1861, A. Agassiz. Hydrarinm. 
Cat. No. 127, Naliant, July, 1861, A. Agassiz. Hydrarium. 
Cat. No. 128, Naliant, August, 1861, A. Agassiz. Hydrarium. 
Cat. No. 129, Naliant, September, 1854, H. J. Clark. Hydrarium. 
Cat. No. 130, Naliant, December, 1854, H. J. Clark. Hydrarium. 
Cat. No. 131, Naliant, March, 1856, H. J. Clark. Hydrarium. 
Cat. No. 400, Naliant, Mass., 1862, A. Agassiz. 
Cat. No. 414, Mingan Islands, N. S., Anticosti Expedition, 1861. 
Museum Diagram No. 18, after L. Agassiz. 



Family EUCOPID^E Gegenb. 

Eucopiclce GEG. (emend Agass.). Zeit. f. Wiss. Zool., p. 241. 1856. 
Eucopidce AGASS. Cont. Nat. Hist. U. S., IV. p. 351. 1862. 

Great confusion has always existed in the identifications made of the 
different species of Campanularians, on account of the difficulty of dis- 
tinguishing in certain stages closely allied species. If, however, we 
are fortunate enough to examine them at the breeding season, when 
the characteristic reproductive calycles of the different species are in 
their full development, our task will be greatly facilitated ; and any 
doubts we may still have of the identity or difference of closely allied 
species will be entirely removed, should we succeed in tracing the 
development of the young Medusa. Although we may find it impos- 
sible to distinguish, at certain stages of growth, young Medusce, it 
by no means follows that these Medusae, which have developed from 
Campanularians easily distinguished, are identical. (Compare the dif- 
ferent Campanularians figured in the sequel.) Whenever we succeed 
in tracing the complete history of any one of our Jelly-fishes, we 
always find that we are able to distinguish readily closely allied 
species, which our previous ignorance had led us to consider as 

XO. II. 11 



82 EUCOPIDJE. 

identica. ; as, for example, the Medusae of Eucope polygena, Eucope 
diapliana, Eucope pyriformis, and Eucope articulata. The strongest 
case we can cite is perhaps that of Syndictyon and Coryne, the adult 
Medusa? of which had long been distinguished by the difference of 
color of the sensitive bulb ; but whether this was anything more than 
mere individual differences could not be ascertained till Ave became 
acquainted with the complete development of the former genus, which 
will be found given in its place in this Catalogue. Hincks, after 
some observations limited to two genera of Hydroids, came to the 
conclusion that we could have Medusa?, generically identical, developed 
from Hydroids generically distinct ; this is so entirely opposed to any- 
thing known in the history of the development of these animals, and 
so totally disproved by the examples of Campanularians here described, 
that I believe that, when the complete history of the two Medusae 
described by Hincks is fully known, we shall find we have only a case 
of very close affinity at one stage of their development, and that, as 
we become acquainted with their more advanced stages, differences will 
be perceptible. 

The different species of Eucopida? found on our coast, of which we 
know the development, explain many of the contradictory statements 
of European writers concerning the mode of development of the dif- 
ferent species of Eucope. It has been shown only more recently that 
many of the species, so closely allied as to be readily mistaken at any* 
time, except the breeding season, were reproduced, on the one hand by 
Planula?, and on the other by Medusa? ; and now it is found that the 
Medusa? produced from Hydroids which have been considered identi- 
cal species, develop into very different adult forms. See, for example, 
the differences in the Medusa? of Laomedea geniculata, figured by 
Wright and Gosse ; one has ovaries and the other has none, imme- 
diately after its escape from the reproductive calycle, as in our Eucope 
dlapliana and Eucope articulata. The Laomedea yelat'mosa of Van 
Beneden has twenty-four tentacles and ovaries, as in our Eucope pyrl- 
formis, to which it is closely allied, while the Medusa of Laomedea 
(jdat'mosa of English writers has sixteen tentacles at first, and is an 
Obelia. The European Campanularians require a thorough revision in 
order to extricate them from the confusion existing in their synonymy, 
and this can only be done after a thorough acquaintance with the de- 
velopment of their Medusae. 

The Laomedea dichotoma of Dalyell is probably the same as the 
Campanularia gelatinosa of Van Beneden. The same confusion oc- 
curs in the fourth volume of Professor Agassiz's Contributions ; the 
Eucope which is there figured as Eucope dlapliana Agass., and the 
Campanularian of that name (Plate 34), is not the Hydroid of Eu- 
cope diapliana, as will be seen in the description of the latter. The 



EUCOPE. 83 

Eucope diaphana of the fourth volume (not that of the Memoirs of the 
American Academy) is probably identical with the English Eucope 
geniculata of Wright, not that of Gosse, and it may hereafter be desig- 
nated as Eucope alternata. 



EUCOPE GEGENB. 

Eucope GEGENB. Versuch eines System ; Zeit. f. "VViss. Zool., p. 241. 1856. 
Eucope AGASS. Coat. Nat. Hist. U. S., IV. p. 351. 1864. 



Eucope diaphana AGASS. 

Eucope diaphana AGASS. (ex p.). Cont. Nat. Hist. U. S., IV. PI. 33, Fig. 2. Hydrarium. 1862. 
Tftaumantias diaptiana AGASS. Mom. Am. Aca<l., IV. p. 300, Figs. 1, 2. 
Eucope diaphana A. AGASS. Proc. Bost. Soc. Nat. Hist., IX. p. 02, Figs. 7-9. 
Tltaumantias diaphana MO'UCH ; in Beskriv. af Gronland, p. 96. 1857. 

This is by far the most common of our Jelly-fishes ; it does not grow 
to a large size, adult specimens not measuring Kig 115 . 

more than a quarter of an inch across the disk. 
On escaping from the reproductive calycle, the 
little medusa has but twenty-four tentacles, and is 
constantly swimming with the disk turned inside 
out, as in Fig. 115 ; at the base of two of the ten- 
tacles (t f , t r . Fig;. 116), situated on both sides of the mid- 

Fig. 116. 

die tentacle, between the chymiferous tubes, are found 
large spherical capsules ; there are no traces of ovaries 
to be found in this early stage, it is not till the second 
set of tentacles begin to develop (2, Fig. 117) that they 
make their appearance. Young tentacles do not pos- 
sess the root-like projection at their Fig 117 . 
base ; this is only developed in older tentacles 
of more advanced Medusae. (See Fig. 120.) With 
advancing age the Medusae lose the habit of 
swimming with the proboscis uppermost, and grad- 
ually assume the usual mode of swimming of Jelly- 
fishes. The young Eucope of Fig. 117 develops 
rapidly additional tentacles, the ovaries increase in 
size, and we soon have an adult Medusa, with large bag-like ovaries, a 

Fig. 115. A Eucope diaphana just after its escape from the reproductive calycle, seen in 
profile. 

Fig. 116. One quarter of the disk of the same, seen from above. ?, tentacle opposite chymif- 
erous tube ; (', <', tentacles with capsules. 

Fig. 117. A more advanced Eucope, in which the second set of tentacles (2) is developing 
between the original tentacles (1). 






84 



EUCOPE DIAPHANA. 



short proboscis, and an extremely attenuated disk, as in Fig. 118. Fig. 

119, which is a still more magnified view of a quarter of the disk, seen 
Fig . 118 . from above, shows the extraordinary increase of 

the number of tentacles, and the position of the 
genital organs near the circular tube. As the 
Medusas become older, a sort of sensitive bulb is 

formed at the base of the tentacles, in which a little pigment matter 

is accumulated (6, Fig. 120) ; this bulb is hardly perceptible in younger 




Fig. 119. 



Fig. 120. 





Fig. 121. 



tentacles, and is totally wanting in the young Medusae. The original 

number of the capsules between every two chymiferous tubes is not 

changed as the tentacles become more numerous ; in adult specimens 

(Fig. 119) there are only two to be found, as in the 

youngest Medusae, just escaped from the calycle. When 

examining a part of the circular tube of a Eucope 

somewhat more advanced than the stage represented in 

Fig. 117, we find only a great increase in the sensitive 

bulbs and the root of the tentacles (r, Fig. 120), but 

we can perceive nowhere, in any of the most advanced 

tentacles, the least trace of additional capsules, such as 

are found in the two tentacles, ', #', Fig. 116, and #', 

Fig. 120. The capsules (c, Fig. 120) have the same 

shape and position they had in younger Medusae. The 

genital organs, at first mere swellings of the chymiferous 
tubes (Fig. 117), soon develop into regular pouches, 
which hang down on both sides of the tube ; the tube 
also forms a sort of pocket at the point of attachment 
of the pouch, (a, a", a'", Fig. 121.) This pocket is read- 
ily seen in the male (Fig. 121) ; its shape, when seen 
from above, changes considerably according to the position of the 
genital pouch, (a, a", Fig. 121.) The shape of the spermaries has 

Fig. 118. An adult Eucope diaphana, seen in profile. 
Fig. 119. A quarter of Fig. 118, more magnified. 

Fig. 120. Magnified view of the circular tube of a young Eucope. 5, sensitive bulb ; r, root 
of tentacle ; c, capsule ; ?', tentacle with capsule. 

Fig. 121. Spermaries ; a', seen from above ; a", in profile ; a"', different attitude from above. 
Fig. 122. Female genital organs. 




Fig. 122. 




EUCOPE DIAPHANA. 



85 



Fig. 123. 




Fig. 124. 




a tendency to be somewhat rectangular or bottle-shaped (Fig. 121), 
while the ovaries, when distended with eggs (Fig. 122), are more 
generally spherical ; the number of eggs in an adult female 
are not numerous, not more than twelve to fifteen ; the eggs 
are quite large, and have a very sharply defined germinative 
vesicle. The proboscis (Fig. 123) lengthens but little in 
older Medusa?, almost the only change being the greater 
mobility of the lips of the actinostome ; the veil is totally 
wanting in young Medusa?, and in the adult is a very nar- 
row ribbon round the circular tube, hardly extending beyond 
the root of the tentacles, so that it easily escapes notice. 

This Medusa is exceedingly phosphorescent, having a very white 
brilliant light, which is given out most strongly at the base of the 

long tentacles. These Medusa? appear as early as 
March, and are found as late as November. The 
Hydrarium (Fig. 124) grows to but little more than 
an inch in height, and resembles Laomedea genlcu- 
lata ; but the absence of the knee at the base of the 
sterile Hydra, and the long ringed branch support- 
ing it, distinguish it at once from that species. The 
calycle is elliptical, arching regularly towards the 
centre, and tapering at the two ends (Fig. 125) ; from twelve to 
fifteen Medusa? develop in each calycle. Found at 
near low-water-mark, attached to the base of Fucus 
vesicidosus. 

It may be that the Medusa of Laomedea yeniculata 
of Gosse, figured on Plate IV. of his "Devonshire," 
may prove to be the young of Thaumantias lucida of 
Forbes, which is the English representative of our 
Eucope diaphana. Should this be the case, the two 
species are evidently distinct, and representative spe- 
cies in the Acadian and Lusitanian Fauna. Is not 
the Medusa fimbriata of Dalyell (PL 52, Figs. 6, 7) 
the same as the Medusa of Laomedea geniculata, and is it not also 
identical with the Thaumantias lucida of Forbes ? 

Massachusetts Bay, Nahant (Agassiz) ; Buzzard's Bay, Naushon (A. 
Agassiz). 

Cat, No. 78, Nahant, July, 1861, A. Agassiz. Hydromedusarium. 
Cat. No. 79, Naushon, Sept. 1861, A. Agassiz. Hydromedusarium. 
Cat. No. 281, Naushon, Sept, 1861, A. Agassiz. Hydromedusarium. 

Fi<T. 123. Proboscis of an adult Medusa. 

o 

Fig. 124. Hydrarium of Eucope diaphana, natural size. 

Fig. 125. Magnified view of sterile Hydra and of a reproductive calycle. 



Fiff. 125. 




86 EUCOPE POLYGENA. 



Eucope alternata A. AGASS. 

Eucope diapJiana AGASS. (ex. p.). Cont. Nat. Hist. U. S., IV. pp. 322, 352, PI. 34, Figs. 1-9. 
1862. Non Th. diaphana AGASS., Meru. Am. Ac. 

This species was at first mistaken by Professor Agassiz for the young 
of Thaumantias diaphana^ figured in the Memoirs of the American 
Academy. The development of the Hydrarium of these two closely 
allied forms shows that two species have been confounded. 

Massachusetts Bay, Nahant (Agassiz). 

Cat. No. 83, Nahant, Mass., Aug. 1861, A. Agassiz. Hydromednsarimn. 

Cat. No. 84, Nahant, September, 1854, H. J. Clark. Hydrarium. 

Cat. No. 85, Nahant, May, 1862, A. Agassiz. Hydrarium. 

Cat. No. 86, Nahant, July, 1861, A. Agassiz. Hydrarium. 

Cat. No. 87, Nantasket, April, 1861, H. B. Rice. Hydrarium. 

Cat. No. 88, Nahant, L. Agassiz. 

Cat. No. 394, Nahant, July, 1862, A. Agassiz. Hydromedusarium. 

Cat. No. 395, Nahant, June, 1862, A. Agassiz. Hydromedusarium. 



Eucope polygena A. AGASS. 

The only adult Medusa of the genus Eucope, of which we know 
the complete development, being Eucope diaphana, it is not possible 
at present to decide whether we have not among these closely allied 
Campanularians the Hydraria of several genera. There are certainly 
differences among the young Medusae, at the moment of escaping 
from the calycles, which must give them totally distinct characters 
when adult, to judge by what we know of the mode of development 
of marginal tentacles, and the increase in size of the genital organs. 
There is a great similarity in the young Medusaa of Eucope articulate^ 
E. pyriformis, E. alternata, and E. polygma, all these species having 
twenty-four hollow tentacles, and ovaries close to the base of the pro- 
boscis, at the time they escape from the reproductive calycles ; while 
in E. diaphana and E. geniculata Gosse we have twenty-four tentacles, 
nearly solid, and no ovaries in the younger stages. Another type 
occurs in Obelia commissuralis and Laomedea gelatinosa of English 
authors, where the Medusa has sixteen tentacles and no ovaries ; 
and finally there is a still different type in the Eucope fusiformis 
and Laomedea divaricata of McCrady, in which we find forty-eight 
tentacles at the time of hatching, and long spindle-shaped genital 
organs along the chymiferous tubes. These are undoubtedly good 
structural characters upon which genera can easily be distinguished, 
but it would be premature to make all these divisions until we know, 



EUCOPE PARASITICA. 



87 



Fig. 126. 



from actual observations, in what manner these differences of the 
young Medusas are carried out in the adult. The Hydrarium and the 
Medusa of several species are described here under the generic name 
of Eucope, simply to call attention to the great structural differences 
found among Campanularians apparently so closely related. 

Eucope polygena is remarkable for the short stems of the sterile 

Hydra, the stoutness of the main 

/ 

stem, and the great number of Me- 
dusae developed in a single reproduc- 
tive calycle ; the bell is flaring, with a 
smooth edge, and rather shallow ; the 
reproductive calycles are elliptical, 
slightly wavy (Fig. 126), and some- 
what bottle-shaped at the extremity. 
The Medusa resembles closely that 
figured by Professor Agassiz as Eu- 
cope diaphana, in Vol. IV. PI. 34, Fig. 
9, Contributions to the Natural His- 
tory of the United States ; the tenta- 
cles are larger in proportion to the 
size of the disk. This species is found 

growing on stems of Laminaria, in small branching tufts, of one to two 
inches in height. 

Cat. No. 393, Nahant, June, 1862, A. Agassiz. Hydromedusarium. 

Cat. No. 399, Nahant, June, 1862, A. Agassiz. Hydromedusarium. 




Eucope parasitica A. AGASS. 

This species is closely allied to the E. polygena ; it has, like it, short 
branches, composed of not more than three or four rings, supporting 
the sterile Hydras ; the inner walls of the stems are parallel to the 
outer wall ; the sterile Hydras go off nearly at right angles to the 
stem ; the reproductive calycles are very graceful, terminating with a 
peculiar mitre-shaped top. The Medusa has twenty-four tentacles ; it 
has thus far only been found growing on a species of Penella, parasitic 
on Orthagoriscus mola. 

Massachusetts Bay, Nahant (A. Agassiz). 

Cat. No. 80, Nahant, August, 1861, A. Agassiz. Hydromedusarium. 

Cat. No. 81, Nahant, August, 1856, L. Agassiz. Hydromedusarium. 

Fig. 126. Magnified view of part of main stem of E. polygena. 



88 



EUCOPE PYRIFORMIS. 




Fig. 128. 



Eucope pyriformis A. AGASS. 

Laomedea gelatinosa LEIDY (iion Auct.). Mar. Inv. New York and Rhode Island, p. 6. 1855. 

rig - 127 - This Medusa has, on its es- 

cape from the reproductive caly- 
cles, small pear-shaped ovaries 
placed close to the digestive 
cavity (Fig. 127), which is short 
and almost globular ; there are 
four chymiferous tubes ; the 
tentacles are shorter than in 
Obelia commissuralis, and not 
as slender ; at the moment of hatching there are twenty-four tenta- 
cles, five between each of the chy- 
miferous tubes (Fig. 128), and two 
large marginal capsules, with one 
granule in each, placed a little on 
one side (towards the circular tube) 
of the two tentacles adjoining the 
middle one between the chymiferous 
tubes ; the lasso cells are arranged in 
broken rings round the tentacles. The 
Hydrarium (Fig. 129) is found growing 
in large quantities on the eel-grass ; 
the Avails of the tube run parallel to 
the outer envelope ; there are no 
knees or breaks in the . continuity, nor are there any swellings where 

the reproductive calycles are attached ; the 
branches are wide apart, the whole tuft spread- 
ing like a bush ; the bell of the hydra is short 
and flaring, and is attached to the main stem by 
a long branch, having from twelve to fifteen 
rings. The reproductive calycles vary greatly 
in shape during their growth ; when small, they 
are almost rectangular, with rounded corners, 
and a slight constriction in the middle ; as they 
become larger, they grow more pear-shaped ; 
and in still more advanced stages the calycles 
assume the shape of an elongated ellipse, with 
a pointed cap, and three or four deep constric- 

Fig. 127. E. pyriformis, seen in profile ; greatly magnified. 

Fig. 1 28. Quarter of disk of same Medusa. 

Fig. 129. Portion of Hydrarium of E. pyriformis ; magnified. 




Fig. 129. 




EUCOPE ARTICULATA. 89 

tions. There are from nine to twelve Medusae growing in each calycle 
at once. 

This species is closely allied to the Campanularia yelatinosa of Van 
Beneclen, and to the Campanularia dichotoma of Dalyell. The details 
of structure of the Hydrarium, especially the reproductive calycles and 
the stem of the sterile Hydra, seem to prove that they are different 
species. The mode of branching is the same in both. Compare Van 
Beneden, PL 1, Fig. 1, Campanulaires de la Cote d'Ostende, and the 
figures of the Medusas here given. 

Point Judith (Leidy) ; Beverly, Massachusetts Bay (Alex. Agassiz) ; 
Grand Manan (Mills). 

Cat. No. 74, Beverly, Mass., July, 1861, A. Agassiz. Hydromedusarium. 

Cat. No. 75, Nahant, Mass., July, 1861, A. Agassiz. Hydromedusarium. 

Cat. No. 76, Grand Manan, Aug. 1857, J. E. Mills. Hydrarium. 

Cat. No. 77, Grand Manan, Aug. 1857, J. E. Mills. Hydrarium. 



Eucope articulata A. AGASS. 

This species is so closely allied to Eucope, pyriformis that the Me- 
dusas can hardly be distinguished. The Medusa of Eucope articulata 
(Fig. 130) has more slender marginal tentacles, and the lips of the 
actinostome are deeply cleft and extremely movable, which is quite 
the contrary of what we find in young Medusas of Eucopidas. The 



Fig. 130. 





Hydrarium is at once recognized by the extraordinary length of the 
ringed branch supporting the sterile Hydras, the cups of which are quite 
deep and narrow. The reproductive calycle (Fig. 131) resembles in 
shape that of Obelia commissuralis., but is in addition supported upon 

Fig. 130. Quarter of the disk of Eucope articulata ; magnified. 
Fig. 131. Portion of a Hydrarium of Eucope articulata. 
NO. II. 12 



90 EUCOPE FUSIFORMIS. 

a Larger pedicel, having from eight to ten rings. It is very common to 
see the sterile Hydra?, placed as in the figure (Fig. 131), in pairs at the 
base of the reproductive calycle. The Hydrarium grows to about the 
size of the Eucope pyriformis, from three to four and even five inches 
high, and is readily mistaken for the Hydrarium of Obelia commissu- 
Talis. It grows in pools on rocks at low-water-mark. 

Cat. No. 396, Nahant, June, 1862, A. Agassiz. Hydromedusarium. 

Cat. No. 397, Nahant, June, 1862, A. Agassiz. Hydromedusarium. 



Eucope ? fusiformis A. AGASS. 

Eucope? A. AGASS. ; in Proc. Bost. Soc. Nat. Hist, IX. p. 91, Fig. 6. 

From a Hydrarium, in which the cavity of the main stem passes 
from one side to the other (s, s, Fig. 132), similar in its mode of 
rig. 132. branching to that of Eucope diapliana, but in which the 

Hydras, remarkable for their small bell, 6, are attached 
to the main stem by short branches, not having more 
than three or four rings (Fig. 132), is produced a small 
Medusa of a sixteenth of an inch in diameter, having, 
when hatched, four long fusiform ovaries (Fig. 133), oc- 
cupying nearly the whole length of the chymiferous 
tubes, and forty-eight long, slender tentacles, having 
well-developed rootlets, usually carried quite stiffly, with 
two marginal capsules between each pair of chymifer- 
ous tubes, occupying the same position as in E. diapha- 
na, when it has forty-eight tentacles. The digestive 
cavity is quite long and movable, and differs from that 
of the last species by the more marked lobes of the actinostome. The 
different species of Eucopida?, thus far described, can easily be distin- 
Fig 133> guished by the number of tentacles, the presence 

or absence of the ovaries, and their position 
when they escape from the reproductive calycles. 
Among the many specimens of E. dlapliana 
which I had occasion to examine, I have only 
found two in which there were not twenty-four 
tentacles on hatching, and in the Obelia commis- 
suratis and E. pyriformis the same holds good ; 
the number of tentacles at the time of escape 
from the calycles being very constant. 
Massachusetts Bay, Nahant (A. Agassiz). 
Cat. No. 90, Nahant, July, 1861, A. Agassiz. Hydromedusarium. 

Fig. 132. Hydrarium of Eucope fusiformis ; magnified. 

Fig. 133. Quarter of the disk of the Medusa of Eucope fusiformis ; greatly magnified. 





OBELIA. 91 

Eucope ? divaricata A. AGASS. 

Laomedea divaricata McCR. Gymn. Charl. Ilarb., p. 03. 

An examination, by Professor Clark, of the reproductive calycles of 
specimens collected at Charleston by Professor Agassiz, shows that the 
Medusre have forty-eight tentacles. The Hydrarium is closely related 
to that of the Eucope pyriformis, which, together with the present 
species, will probably form the basis for a new genus. 

Charleston, S. C. (L. Agassiz). 

Cat. No. 82 ; Charleston, S. C., January, 1852, L. Agassiz. 

OBELIA PER. et LES. 

Obella PER. et LES. ; in Ann. clu Mus., XIV. p. 43. 1809. 
Obelia AGASS. Cont. Nat. Hist. U. S., IV. p. 351. 18C2. 
Obdia McCR. Gynm. Charl. Harb., p. 94. 



Obelia commissuralis 

Obelia conanissuralis McCR. Gymn. Charl. Ilarb., p. 95, PI. 11, Figs. 5-7. 

Obelia commissuralis AGASS. Cont. Nat. Hist. U. S., IV. pp. 315, 351, Pis. 33 (non Fig. 2), 34, 

Figs. 10-21. 1862. 

Ohrlia commissuralis A. AGASS. Proc. Bost. Soc. Nat. Hist., IX. p. 91, Fig. 5. 
Laomedea dichotoma LEIDY (non Auct.). Mar. Inv. N. J. and R. L, p. 6, PI. XI. Fig. 36. 1855. 
Laomedea gelatinosa STIMPS. (non Auc-t.). Mar. Inv. Grand Manan, p. 8. 1853. 
Laomedea gelatinosa GOULD. Rep. Inv. Mass. Bay, p. 350. 1841. 

The Obelia commissuralis of McCrady, which extends from Charleston 
to the coast of New England, and even as far as Grand Manan, has an 
exceedingly slender polypidon and Fig . m . 

branches very profusely; the branches, 
stretching in graceful curves on both 
sides of the main stem, reach their 
greatest length about midway, and 
then taper very gradually towards the 
upper extremity. It can at once be 
distinguished on account of its pecu- 
liar mode of growth ; it attains from 
five to six and even seven inches in 
length. At the time when it bears 
reproductive calycles, it is still more 
easily distinguished from the allied 
species by the shape of the calycles ; 
they are slender, conical, the base of the cone with its rounded edges 
being surmounted by a short neck (Fig. 134) ; they bear from ten to 

Fig. 134. Portion of stem of Hydrarium of Obulia commissuralis. 




fig. 135. 




92 OBELIA COMMISSURALIS. 

twelve and even sixteen Medusae. The young Medusa (Fig. 135), when 
hatched, has sixteen tentacles, four chymiferous tubes, a rather long 
cylindrical digestive cavity, with four labial lobes ; there are no ovaries 
yet developed. I have not found these Medusae in a more advanced 
condition, though they become free in the first weeks of July, and are 
found during the whole summer, as late as September, 
but in no case were there any ovaries developed. In 
confinement they do not prosper, and after a few days 
die, without assuming a different shape from that in 
which they become free. The tentacles are slender, as 
long as the diameter of the disk ; in two of the tentacles 
there are large marginal capsules in a swelling on the under side ; the 
re-entering spur of the tentacles is small. There is considerable differ- 
ence between the Hydrarium of the specimens found at Charleston and 
those of our coast ; the Charleston specimens are uniformly thinner 
and more slender ; it remains yet to be seen whether any further spe- 
cific differences can be detected in the Medusae. If Van Beneden's 
figure of the Campanularia geniculata is correct, the European and the 
American species of Obelia are distinct. 

Absecom Beach (Leidy) ; Charleston (McCrady) ; Buzzard's Bay, 
Naushon (A. Agassiz) ; Massachusetts Bay and Grand Manan (Agassiz). 

Cat. No. 65, Charleston, S. C., January, 1852, L. Agassiz. Hydrome- 
dusarium. 

Cat. No. 66, Charleston, S. C., February, 1852, L. Agassiz. Hydrome- 
dusarium. 

Cat. No. 67, Nahant, July, 1861, A. Agassiz. Hydromedusarium. 

Cat. No. 68, Nahant, July, 1861, A. Agassiz. Hydromedusarium. 

Cat. No. 69, Nahant, July, 1861, A. Agassiz. Hydromedusarium. 

Cat. No. 70, Nahant, Sept. 1861, A. Agassiz. Hydromedusarium. 

Cat, No. 71, Grand Manan, Sept. 1857, J. E. Mills. Hydromedusarium. 

Cat. No. 72, Nahant, July, 1857, L. Agassiz. 

Cat. No. 73, Newport, R. L, Dr. Leidy. 

Cat. No. 392, Nahant, July, 1862, A. Agassiz. 

Fig. 135. Quarter-disk of the Medusa of Obelia comniissuralis. 



LAOMEDEA. 93 



LAOMEDEA LAMX. 

Laomedea LAMX.; in Bull. Soc. Phil. 1812. 

Laomedea AGASS. Cont. Nat. Hist. U. S., IV. p. 352. 1862. 

Campanularia LAMK. (p. p.). An. s. Vert., II. p. 129. 



Laomedea rigida A. AGASS. 

This species is remarkable for its peculiar mode of growth. At first 
glance it would readily be mistaken for a species of Dynamena, so 
regular is the succession of the hydroe along the stem, and also on 
account of the absence of branches. The sterile and reproductive hy- 
dras are found on the sides of the main stem, attached by a very short 
pedicel, and alternate so regularly on each side that its Campanularian 
nature is noticed only after a careful examination. The sterile hydrne 
resemble those of Laomedea amphora, while the reproductive calycles 
are identical in shape with those of Obelia commissuralis. The main 
stems of a cluster are closely crowded together, and attain a height of 
three to four inches. 

Cat. No. 122, San Francisco, Cal., December, 1859, A. Agassiz. Hy- 
d rome dusarium. 



Laomedea amphora AGASS. 

Laomedea amphora AGASS. Cont. Nat. Hist. U. S., IV. pp. 311, 314, Fig. 50 ; p. 352, Pis. 30, 31, 
Figs. 1-8. 1862. 

Massachusetts Bay (Agassiz) ; Grand Manan (Mills) ; Long Island 
Sound (Leidy, A. Agassiz). 

Cat. No. 91, Nahant, July, 1852, H. J. Clark. Hydromedusarium. 

Cat, No. 92, Nahant, July, 1861, A. Agassiz. Hydromedusarium. 

Cat, No. 93, Nahant, July, 1861, A. Agassiz. Hydromedusarium. 

Cat. No. 94, Nahant. March, 1861, H. J. Clark. Hydromedusarium. 

Cat. No. 95, Nahant, April, 1855, H. J. Clark. Hydrarium. 

Cat, No. 96, Nahant, 1857, L. Agassiz. Hydrarium. 

Cat, No. 97, Nahant, March, 1856, H. J. Clark. Hydromedusarium. 

Cat. No. 98, Naushon, Sept, 1861, A. Agassiz. Hydromedusarium. 

Cat. No. 99, Grand Manan, Aug. 1857, J. E. Mills. Hydromedusarium. 

Cat, No. 100, Newport, R. I., S. Powell. Hydromedusarium. 

Cat, No. 101, Newport, R I., Dr. J. Leidy. Hydromedusarium. 

Cat. No. 102, Boston, March, 1856, H. J. Clark. 

Cat. No. 114, Nahant, Sept, 1854, H. J. Clark. Young ? 

Cat, No. 398, Nahant, July, 1862, A. Agassiz. 

Museum Diagram No. 18, after L. Agassiz. 



94 LAOMEDEA. PACIFICA. 

Laomedea gigantea A. AGASS. 

This species of Laomedea, found growing in the brackish water of 
Charles River, grows to an enormous size, as much as fifteen to twenty 
inches. It sends off only short branches from the stout principal stem, 
so that in its general appearance it resembles somewhat Sertularia 
cupressina ; the branches, however, are very closely arranged round the 
main stem ; near the extremity we often find, in very large specimens, 
the branches spreading out somewhat fan-shaped. It can readily be 
distinguished from its congener, the L. amphora, by the shape of the 
calycles, which are totally different ; they are elliptical, flaring but 
slightly towards the opening, and taper off somewhat suddenly, with 
a bottle-shaped extremity entirely unlike the calycles of L. amphora. 

Boston Harbor (H. J. Clark). 

Cat. No. 103, Boston, July, 1861, H. J. Clark. Hydromedusarium. 

Cat. No. 104, Boston, July, 1861, H. J. Clark. Hydromedusarium. 

Cat. No. 105, Boston, July, 1861, H. J. Clark. Hydromedusarium. 



Laomedea pacifica A. AGASS. 

This is another gigantic species closely allied to Laomedea amphora ; 
the reproductive calycles are similar in both ; the main stem of this 
species is exceedingly stout ; the mode of branching resembles that of 
L. gelatinosa. Specimens of this species have been collected by Dr. 
Stimpson, of the North Pacific Exploring Expedition under Commo- 
dore Rodgers, in Behring's Straits, and in Avatska Bay, Kamtschatka. 

Gulf of Georgia, W. T. (A. Agassiz) ; San Francisco, Cal. (A. Agassiz). 

Cat. No. 117, Gulf of Georgia, W. T., June, 1859, A. Agassiz. 

Cat. No. 118, San Francisco, Cal., December, 1859, A. Agassiz. 

Cat. No. 120, San Francisco, Cal., December, 1859, A. Agassiz. Hy- 
d rome d usarium. 



95 



Family jEQUORIDjE Esch. (rest AG.) 

jEquorirhc ESCH. (emend. Agass.). Syst. d. Acal., p. 108. 1829. 
jEquoridw AGASS. Cont. Nat. Hist. U. S., IV. p. 359. 18G2. 



RHEGMATODES A. AGASS. 

Rhegmatodes A. AGASS. ; in Agass. Cont. Nat. Hist. U. S., IV. p. 361. 1862. 

Umbrella flat, chymiferous tubes numerous, digestive cavity short, 
with small lips scarcely fimbriated ; the chymiferous tubes extend 
along the prolongation of the umbrella into the cavity of the bell ; 
large tentacles, somewhat more numerous than the chymiferous tubes, 
very contractile. To this genus I suppose that Gosse's ^Equoreaforbes- 
iana belongs; it is closely allied to Stomobrachium Brandt (non Forbes), 
and differs from it in not having numerous long marginal tentacles, in 
the greater number of radiating tubes, and the numerous short lips at 
the extremity of the digestive cavity. Like ^Equorea and Zygodactyla, 
it has marginal capsules, and the peculiar spur at the base of the large 
tentacles. Two species of this genus have been noticed on our coast ; 
the one in Florida, bv Professor Agassiz, and the other at Naushon. 

Rhegmatodes tenuis A. AGASS. 

Rhegmatodes tenuis A. AGASS. ; in Agassiz's Cont. Nat. Hist. U. S., IV. p. 361. 1862. 

This is a large species ; specimens measuring between three and four 
inches have frequently been found. The spherosome is thick (Fig. 136) 
along the polar axis, bulging, in the shape of a rounded obtuse cone, 




Fig. 136. A profile view, natural size, of Rhegmatodes tenuis. 



RHEGMATODES TENUIS. 



Fig. 137. 



into the interior cavity ; the chymiferous tubes extending nearly to the 
apex, leaving but a short digestive cavity, the edges of which scarcely 
meet (Fig. 137), so that, when the actinostome is closed, the lips resem- 
ble a piece of catgut tied by a string close to the end ; the marginal 

tentacles are long, gener- 
ally carried extended, and 
when contracted twist only 
two or three times, and are 
not carried tightly curled, 
as in Zygodactyla ; the ova- 
ries are very narrow, and 
extend almost the whole 
length of the chymiferous 
tubes, from the upper mar- 
gin of the digestive cav- 
ity, to about one tenth the 
length of the radiating tube 
from the circular tube ; the 
ovaries hang down in two 
masses on each side of the 
chymiferous tubes ; there is 
no connection between the 
two pouches, except near 
their point of attachment, 
where they unite again. 

Younger specimens, meas- 
uring about one and a half 
to two inches, and not hav- 
ing more than sixteen to twenty-four chymiferous tubes, resemble Sto- 
mobrachium ; they differ, however, in the small number of tentacles. 
The marginal capsules are large, elliptical ; the granules placed far 
apart, two in each (c, Fig. 138) ; the tentacles taper rapidly from the 
base (t, Fig. 138), the walls are thin, the lasso cells scattered irregularly 

over the whole surface. At the base of the 
large tentacles we find a very prominent pro- 
jection (s, Fig. 138), in the shape of a small 
tentacle opening into the circular tube: it is not 
exactly a spur, as in Lafcea ; it develops only 
after the rudimentary tentacles, being a button 
scarcely to be recognized when the tentacle is 
already quite well formed ; there are usually only rudimentary tenta- 

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

Fig. 138. A magnified portion of the circular canal, showing the position of the spur of the 
tentacles, s, s, and of the marginal capsules, c, between the tentacles, t. 





RHEGMATODES FLORIDANUS. 97 

cles between the chymiferous tubes, except one large tentacle in the 
middle of the space ; there is always one marginal capsule between the 
adjoining tentacles. These Medusae are slow in their movements, allow- 
ing themselves to be carried along with the current, after one or two pul- 
sations ; they swim near the surface. Found at Naushon in September. 

Buzzard's Bay, Naushon (A. Agassiz). 

Cat. No. 278, Naushon, September, 1861, A. Agassiz. Medusa. 



Rhegmatodes floridanus AGASS. 

PJicgmatoJes floridanus AGASS. Cont. Nat. Hist. U. S., IV. p. 361. 1862. 

A second species of this genus (Fig. 139) is found along the Florida 
Reefs. It resembles the young of the northern species at the time 
when it has from sixteen to twenty-four chymiferous tubes ; the part of 
the gelatinous disk which projects into the interior cavity of the bell is 
larger, giving the spherosome a somewhat heavy look ; the fringes of 
the actinostome are longer ; the ovaries are confined to a small part of 
the chymiferous tubes, and do Fig. 139. 

not begin at the point of junc- 
tion of their upper extremity, 
but a short distance from it; the 
circular tube is large ; in speci- 
mens having sixteen chymiferous 
tubes, there were forty marginal 
tentacles ; in specimens having 
twenty, there were sixty. This 
species is much smaller than its 
northern representative, speci- 
mens having already sixteen chy- 
miferous tubes not being more 
than an inch in diameter ; while 
specimens of the northern species, which have attained the same de- 
velopment, measure about two inches. The marginal capsules contain 
two to three granules each. 

Additional chymiferous tubes in the jEquoridaa are developed from 
the digestive cavity, as has already been shown by Kolliker, and 
not from the vertical tube, as is the case in the branching tubes of 
Willia. They are at first simple short sacs, which gradually extend in 
length till they become long tubes, opening into the circular tube ; the 
chymiferous tubes and the marginal tentacles are not developed with 
equal regularity, in the order of their cycles ; the chymiferous tubes 
especially are very irregularly formed, and nothing is more common 

Fig. 139. Rhegmatodes floridanus, natural size. 

NO. II. 13 




98 STOMOBRACHIUM. 

than to find specimens having twenty or twenty-two chymiferous tubes, 
instead of the normal number. The same is the case in the order of 
development of the chymiferous tubes of Zygodactyla, and the other 
^Equoridse which I have had occasion to observe. The tubes are fre- 
quently added all on one side of the spherosome, and will be nearly 
fully formed before they begin to be developed in the other half. The 
specimens observed of this species are evidently not full-grown, as the 
ovaries were but imperfectly developed. 
Key West, Florida (L. Agassiz). 

STOMOBRACHIUM BRANDT. 

Stomobracliium BR. (non Forbes). Prod. ; in Mem. Acad. St. Petersb., p. 220. 1835. 
Stomobrachium LESS. Zooph. Acal., p. 315. 1843. 
Stomobrachium AGASS. Cont. Nat. Hist. U. S., IV. p. 361. 18G2. 

Stomobrachium tentaculatum AGASS. 

Stomobrachium tentaculatum AGASS. Cont. Nat. Hist. U. S., IV. p. 361. 1862. 
S/omobrachium lenticulare GOULD (non Br.). Rep. Inv. Mass., p. 349. 1841. 
? Medusa bimorpha FAB. Fauna Gronlandica, No. 356. 1781. 

This species is occasionally found at Nahant during July. It has 
twelve chymiferous tubes, a small digestive cavity, the folds of the acti- 
nostome hanging down in four lobes, placed at right angles to one 
another ; these lobes are triangular (Fig. 140), the apex of the triangle 

Fig. 141. 



Fig. 140. 





being placed nearer the origin of the chymiferous tubes ; the edges 
are frilled ; the trend of the triangles is in the direction of four of 
the chymiferous tubes. Between each two of the chymiferous tubes 
(Fig. 141) there are from thirty to forty tentacles, in all stages of 

Fig. 140. The actinostome of Stomobracliium tentaculatum, magnified to show the peculiar 
mode of carrying the folds of the digestive cavity. 

Fig. 141. Stomobrachium tentaculatum, seen from the abactinal pole; natural size. 




HALOPSIS. 99 

development ; they are not capable of great expansion, and when short- 
ened, the extremities are curled up. The ovaries, which are linear, 
extend along the chymiferous tubes in such a way as to leave both the 
actinal and abactinal extremities free (Fig. 142) ; the spherosome in- 
creases very gradually in thickness from the circular tube towards the 
abactinal pole. This species differs 
from the S. lenticulare of the Falk- 
land Islands, in having a smaller 
free area, longer chymiferous tubes, 
and more numerous tentacles ; it 
grows from one and a half to two 
inches in diameter, and half an inch 
in height, is sluggish in its movements, is colorless, and has a gelatinous 
disk of considerable consistency. These Medusas are frequently found 
thrown up on the sandy beaches, encased in sand in such a way as to 
be preserved from decomposition and loss of shape for several days. 
This may explain the mode in which the few fossil Medusse known 
have been formed. 

Massachusetts Bay, Nahant (L. Agassiz). 



HALOPSIS A. AGASS. 

Halopsis A. AGASS. ; in Proc. Bost. Soc. Nat. Hist., IX. p. 219. 1863. 

\ 

The genera Berenix and Carisochroma have been placed by Professor 
Agassiz among the Williadce on account of their forking chymiferous 
tubes. The discovery of Halopsis shows this association to be un- 
natural, and that most probably, when the genera Berenix and Cariso- 
chroma ai'e better known, they will be associated with Halopsis into a 
distinct family, the Berinicidre of Eschscholtz. Whatever may be the 
result, it is at least highly probable that their closer relations are with 
the J^quoridce, and not with the Tubularian family of the Williadae. 

Halopsis ocellata A. AGASS. 

Halopsis ocellata A. AGASS. ; in Proc. Bost. Soc. Nat. Hist., IX. p. 219. 1863. 

The genus Halopsis differs from the other ^Equoridre by the presence 
of large compound eyes, as in Tiaropsis, from three to six between 
every two of the chymiferous tubes. There are likewise long tentacu- 
lar cirri ; the flatness of the disk, the large number of tentacles, the 
nature of the digestive cavity and of the genital organs, place this 
genus among the /Equoridte. Two species are found on our coast, 

Fig. 142. The same as Fig. 141, seen in profile. 




100 HALOPSIS OCELLATA. 

which are so closely allied that, were not the complete history of their 
Fig . 143 earlier stages known, they would readily have 

been mistaken for different ages of the same 
species. 

The first species, Hatopsis ocellata, would 
at first glance be taken for a Stomobra- 
chium ; on examination we find that the chy- 
miferous tubes take their origin in clusters 
of three to five (in adults), radiating, like the 
spokes of a fan (Fig. 143), from a large cross- 
shaped cavity (Fig. 144), from which hangs 
down a short digestive cavity, terminating in 
four lips. When seen in profile, the disk is 
quite flat, regularly arched, the genital organs 
extend nearly to the circular tube (Fig. 145), 
occupying almost the whole length of the 
chymiferous tubes. The tentacles are very 
numerous, and capable of great expansion and 
contraction (Figs. 143, 145) ; there are as 
many tentacular cirri as tentacles (c, Fig. 146) ; they are long, slender, 
of uniform diameter ; the main tentacles (t, f, Fig. 
146) bulge out prominently immediately at the 
circular tube, tapering very rapidly. The com- 
pound eyes are large (e, Fig. 146); the granules in 
them are arranged in two rows, from six to seven 
in each row (Fig. 147) ; the structure of these 
compound eyes is similar to those of Tiaropsis. 
These Medusa? are exceedingly sluggish in their 
movements ; they are colorless, the genital organs 
having a slight grayish tinge at the time of spawning. Found at Nahant, 
from July to September, quite commonly. In young specimens, meas- 

Fi g . 145. uring not more than an 

inch in diameter, there 
are only four chymif- 
erous tubes (Fig. 148), 
uniting in the form of 
a cross ; there are no 
signs of genital organs ; 
the shape of the disk is somewhat more hemispherical than in the 

Fig. 143. Portion of the disk of Halopsis ocellata, seen from the abactinal pole, somewhat 
reduced. 

Fig. 144. Cavity from which the chymiferous tubes radiate, d, opening of actinostome ; c, 
chymiferous tube ; ft, connecting fold between the point of attachment of two chymiferous tubes ; 
Z, lips of actinostome. 

Fig. 145. Profile of Halopsis ocellata ; natural size. 





HALOPSIS OCELLATA. 



101 



Fig. 146. 



adult. Specimens measuring an inch and a half in diameter have 
as many as twelve chymiferous 
tubes, the cavity from which the 
tubes originate being irregularly 
shaped ; it is not till the Medusa 
measures from two to two and a 
half inches in diameter, that it 
takes the regular star-shaped form 
of Fig. 143 ; it is then also that the 
genital organs first appear, like 
threads on each side of the tubes. 
Additional chymiferous tubes are 
formed quite irregularly as diver- 

ticula sent off from the digestive pouch, as in other ^Equoridoe. It is 
quite a common thing in this species to have two actinostomes, in speci- 
mens where the central cavity is very elongated and irregular in out- 
line, a beginning, perhaps, of a transverse fission similar to that observed 
by Kbllikcr in Stomobrachium, but which I have never noticed in our 
species. In a still younger Medusa (Fig. 149), not measuring more than 
a fifth of an inch in height, and which I suppose to be the young of this 
species (it cannot be the young of Tiaropsis diademata ; see the draw- 
ings of the young of that species), we find already four eyes between 

Fig. 149. Fig. 150. 





Fig. 147. 



Fig. 148. 






two of the chymiferous tubes (Fig. 150), but having only two to three 
granules in each, one large tentacle at the base of the chymiferous 
tubes, one in the middle, and rudimentary tentacles of the third set in 
the intermediate spaces ; on each side of these rudimentary tentacles 
are long cirri ; there are no ovaries. It is interesting to see that among 
the ^Equorida?, the flattest of our Medusae, the young have a deep bell 
(Fig. 149), which becomes gradually shallower, as in the other Campanu- 
larians. The deep bell of the young Halopsis is totally different from 
the other form of young Jilquorea figured hereafter, which resembles 

Fig. 146. Magnified part of circular tube, c, tentacular cirri ; e, compound eye ; , main ten- 
tacles. 

Fig. 147. Magnified view of one of the eyes, to show arrangement of granules. 

Fig. 148. Young Halopsis ocellata, natural size. 

Fig. 149. Young Halopsis ocellata, a fifth of an inch in height. 

Fig. 150. Magnified portion of circular tube of Fig. 149. c, c, c, c, cirri ; at base of each is 
placed an eye. 



102 



HALOPSIS CRUCIATA. 



more a Eucope. This may eventually show us two modes of develop- 
ment among the JEquoridae into forms, forming groups corresponding to 
those of the OceanidoB and Eucopidse as here limited, in one of which 
the young Medusa has a deep bell and few tentacles, as in Clytia and 
Oceania, while in the other group they have, when hatched from the 
reproductive calycles, a flat disk and many tentacles, as in Eucope and 
Obelia. 

Massachusetts Bay, Nahant (A. Agassiz). 

Cat. No. 364, Nahant, August, 1862, A. Agassiz. Medusa. 

Cat. No. 375, Nahant, 1863, A. Agassiz. Medusa. 




Halopsis cruciata A. AGASS. 

During the early part of the summer there is frequently found a 
Medusa, at first supposed to be the young of Halopsis oceUata ; a com- 
parison of the size, the character of the genital organs, and the number 

of tentacles, shows this to be im- 
possible. If. cruciata never grows 
to more than one and a half to two 
inches in diameter. The tentacles 
are much less numerous (Fig. 151), 
the genital organs are lobed pouch- 
es, hanging down in folds from the 
chymiferous tubes ; there are only 
three compound eyes between ev- 
ery two of the chymiferous tubes ; 
these three eyes are already pres- 
ent in the youngest Medusa3 ob- 
served, which measure hardly half an inch in diameter, and in which 
the genital organs are already well developed, while in the young of 
If. ocellata, in specimens measuring nearly two inches, and having as 
many as twelve chymiferous tubes, we find no trace of them. The bell 

of these young Medusae is very high ; the eyes 
differ from those of If. oceUata, having only four 
or five granules arranged in a single row ; the 
tentacular cirri and the large tentacles are essen- 
tially the same in both species ; the spermaries 
of the males are quite slender and more linear, 
compared to the heavily filled, convoluted genital 
pouches of the females. The genital organs are 
of a light pink color, as well as the bell. 

Fig. 151. A profile view, somewhat magnified, of Halopsis erucia 
Fig. 152. A natural attitude of the same species ; both females. 




ZYGODACTYLA. 103 

May not the T. gibbosa of Forbes be a young Halopsis ? They re- 
semble the young of this .species ; also T. globosa, and perhaps T. pilo- 
sella. We have here again one of those ever-returning questions of the 
generic identity or difference of species, showing great structural differ- 
ences, such as we find between these two species ; the discovery of the 
Hydrarium will settle the point. H. cruciata, with its high bell (Figs. 
151, 152), its four chymiferous tubes, the nature of its compound eyes, 
and its habits, would seem to be associated with Tiaropsis, among the 
OceanidaB ; while the tentacular cirri and the arrangement of the com- 
pound eyes place it in the closest relationship to H. ocellata. 

Massachusetts Bay, Nahant (A. Agassiz). 

Cat. No. 374, Nahant, 1863, A. Agassiz. Medusre. 

Cat. No. 379, Nahant, June, 1862, A. Agassiz. Medusse. 

Cat. No. 445, Nahant, June, 1864, A. Agassiz. Medusae. 



ZYGODACTYLA BRANDT. 

Zygodaclyla BR. Prod. ; in Mem. Acad. St. Petersburg, p. 221. 1835. 
Rhacostoma AGASS. ; in Proc. Bost. Soc. Nat. Hist., III. p. 342. 1850. 



Zygodactyla groenlandica AGASS. 

Zygodactyla groenlandica AGASS. Cont. Nat. Hist. U. S., IV. p. 360. 1862. 

JEquorca r/rocnlandica PER. et LES. ; in Ann. du Mas., XIV. p. 27. 1809. 

Medusa aquorea FAB. Fauna Groenlandica. No. 357. 1780. 

Rhacostoma atlanticum AGASS. ; in Proc. Bost. Soc. Nat. Hist., III. p. 342. 1862. 

^Equorca globularis MORCH. ; in Besk. af Gronland, p. 96. 1857. 

JEquorea groenlandica LESS. Zooph. Acal., p. 313. 1843. 

This species, of which a short description was given by Professor 
Agassiz in the Proceedings of the Boston Society of Natural History for 
1850, who supposed it to be an undescribed species, is one of the largest 
of our naked-eyed Medusa3. It is not uncommon to find specimens meas- 
uring as much as fifteen inches in diameter when fully extended. There 
are in full-grown specimens from eighty to a hundred chymiferous tubes 
(Fig. 153), with three and even four long retractile marginal tentacles 
between every two chymiferous tubes ; the pendent membrane, which 
forms the digestive cavity, is very contractile, having a circular opening, 
with short lips and fimbriated edges, corresponding to the chymiferous 
tubes, which appear to be hardly long enough, when expanded (Fig. 153), 
to close up the edges, while at other times the lips of the actinostome 
hang down far below the level of the circular canal, like a sheaf (Fig. 
154), and at other times the lips hang down loosely from what seems a 
small opening, or flare out so as to measure five or six times the diam- 
eter of their base. The chymiferous tubes extend a short distance down 



104 



ZYGODACTYLA GROENLANDICA. 



Fig. 153. 




Fig. 154. 



the bulging part of the spherosome, the free space left in the centre 

having a radius of about 
one third that of the 
spherosome itself. The 
lips of the actinostome 
are formed by the folding 
of the membrane of the 
digestive cavity along the 
direction of the radius ; 
as the membrane becomes 
more and more fimbri- 
ated, the fold becomes 
deeper and deeper, and 
projects beyond the gen- 
eral outline, like an ex- 
ceedingly delicate frill. 
The tentacles at the base 
are swollen, taper very 

suddenly, are hollow (Fig. 155), the walls of the tentacles are thin, 

and the lasso cells are arranged irregularly over the whole surface in 

small clusters. At the base 

of each of the large tentacles 

there is a small hollow spur 

(s, Fig. 155) projecting inward, 

the walls of which are thick, 

and made up of large cells ; 

the rudimentary tentacles are 

swollen at the extremity, and 

the spur is not developed until 

the lash of the tentacle be- 
comes apparent ; the marginal capsules are large, ellipsoid, with two 

large granules in each. In young specimens of Zygodactyla, not hav- 
ing more than forty large chymif- 
erous tubes reaching to the mar- 
gin, we find the other tubes but 
slightly developed, two or three 
sometimes between each of the 
larger tubes extending from the 
upper edge of the digestive cav- 
ity to various distances from it ; 

Fig. 153. Abactinal view of Zygodactyla groenlandica. 
Fig. 154. Profile view of Fig. 153, half natural size. 

Fig. 155. Portion of the circular tube, showing the mode of development of the marginal ten- 
tacles, s, spur of marginal tentacles. 





ZYGODACTYLA GROENLANDICA. 105 

these rudimentary tubes are mere threads, running a short distance, 
and then suddenly terminating, or tapering gradually to a point. In 
the latter part of June, or early in July, the Zygodactyla? are all in this 
condition, while later in the season, in August and the latter part of 
September, they attain their full size, all the chymiferous tubes being 
about equally developed. The lips of the actmostome are so read- 
ily movable that the outline of its edge will assume the most varied 
shapes, the opening being either concentric and perfectly circular, 
or else thrown entirely to one side, or assuming a pear-shaped form, 
closing at another time like the actinostome of an Actinia, and then 
suddenly spreading into a pentagonal opening ; or the membrane of 
the digestive cavity is expanded to its fullest capacity, extending far 
below the circular tube, and leaving but a very small elliptical acti- 
nostome, from which a sheaf of long, slender, highly fimbriatecl, lance- 
olate lips are suspended. 

Notwithstanding the facility with which this species is kept alive, I 
have never succeeded in raising the eggs, as is so easily done with 
Tima and Melicertum, and can therefore add nothing to the observa- 
tions of Wright on the Hydrarium of ^Equorea vitrma. 

Among the numerous young Eucopida?, daily examined, are fre- 
quently found exceedingly small Medusa?, not larger than the head 
of a pin, which I suppose to be the young of Zygodactyla. They 
resemble the Eucopida?, but differ in having 
rather more slender tentacles, and a very 
peculiar gelatinous projection of the disk, at 
the base of which are situated four round 
genital organs (Fig. 15G) ; there are four 
chymiferous tubes opening into a large cav- 
ity, leading into a slightly pendent stomach, 
exactly as would be the case in a Zygodac- 
tyla, if we were to reduce the chymiferous 
tubes to four, and make the genital organs 
round. The youngest Medusa? have already twenty-four tentacles, 
and the next size, scarcely larger, forty-eight ; from this large number 
of tentacles, as well as the peculiar projection of the gelatinous disk, 
and the large cavity from which the chymiferous tubes take their 
origin, I have but little doubt that they are the young of ^Equoricla?, 
probably of our Zygodactyla. The small size of these Medusa?, coupled 
with their habit of living at the bottom, till late in the fall, when 
they make their appearance as full-grown Medusa?, will readily account 
for their having escaped our notice thus far. These young ^Equorida? 
are quite common early in June ; their further development could not 
be traced, as they do not thrive in confinement. 

Fig. 156. Young Zygodactyla, greatly magnified. 
NO. n. 14 




106 



ZYGODACTYLA CRASSA. 



Greenland (Fabricius) ; Maine, and Massachusetts Bay (L. Agassiz) ; 
Naushon (A. Agassiz). 

Cat. No. 277, Naushon, September, 1861, Alex. Agassiz. Medusa. 



Zygodactyla crassa A. AGASS. 

This species, which grows to almost as large a size as Zygodactyla 
groenlandica, can be recognized at first glance by the small number 
and great size of the genital organs ; there are not more than thirty- 
two chymiferous tubes (Fig. 158) in a Medusa measuring ten inches in 
diameter, while in a specimen of Z. groenlandica of the same size we 
should find at least eighty to ninety ; the ovaries have an extraor- 
dinary development, and bulge out at the time of spawning fully as 
much as the ovaries of Melicertum, hanging very much in the same 

Fig. 15T. 




manner from the chymiferous tubes (Fig. 157) ; the radius of the 
digestive cavity is larger ; the number of lips of the actinostome cor- 
responds to that of the radiating tubes (Fig. 158); the digestive cavity 
is far less capable of expansion and contraction than in Z. groenlan- 
dica ; the marginal tentacles are much heavier and more massive ; the 
color of the base is slightly greenish-blue, as well as the genital 
organs ; the latter have a rather more yellowish hue. Found at 

Fig. 157. Profile view of Zygodactyla crassa, somewhat reduced in size. 



ZYGODACTYLA CYANEA. 



107 



Fig. 153. 




Nahant, in company with the Z. cjroenlandlca. The color of the males 
is somewhat more pinkish than that of the females. 
Massachusetts Bay, Nahant (A. Agassiz). 



Zygodactyla cyanea AGASS. 

Zygodactyla cyanea AGASS. Cont. Nat. Hist. U. S., IV. p. 361. 1862. 



This species is of a light-blue color ; can read- 
ily be distinguished from Z. groenlandica by the 
great thickness of the spherosome, and the large 
digestive cavity ; the actinostome is bordered by 
a number of very small and finely fimbriated 
lips (Fig. 159) ; the chymiferous tubes do not 
curve down and extend along the projection of 
the spherosome in the inner cavity of the bell ; 
at their highest point they empty into the diges- 
tive cavitv, the radius of which is more than one 

*/ ' 

half that of the spherosome itself, leaving but a 
short space between the abactinal edge of the 
digestive cavity and the circular tube ; the chy- 
miferous tubes are numerous, ninety to a hun- 
dred, usually placed opposite a long and exceed- 
ingly contractile tentacle ; these are generally 

Fig. 158. Quarter of the disk of Z. crassa. 

Fig. 159. Portion of the disk of Zygodactyla cyanea, from the abactinal pole. 



Fig. 159. 




108 CREMATOSTOMA. 

carried curled tightly to the edge of the disk. Found in great num- 
bers, from February to May, along the Florida Reef 

Florida, Key West (L. Agassiz). 

Cat. No. 349, Florida, L. Agassiz. Medusa. 

Cat. No. 350, Tortugas, Fla., May, 1858, L. Agassiz. Medusa. 



Zygodactyla coerulescens BR. 

Zygodactyla coerulescens BR. ; in Mem. Acad. St. Petersb., p. 360, PI. 5. 1838. 
Zygodactyla coerulescens AGASS. Cont. Nat. Hist. U. S., IV. p. 360. 1862. 
Mesonema coerulescens BR. ; in Mem. Acad. St. Petersb., p. 360. 1838. 
Mesonema ccerulescens LESS. Zooph. Acal., p. 307. 1843. 

Entrance of Straits of Fuca (A. Agassiz). 



CREMATOSTOMA A. AGASS. 

Crematostoma A. AGASS. ; in Agassiz's Cont. Nat. Hist. U. S., IV. p. 360. 1862. 

The genera of ^Equoridse found on the Pacific coast are either 
identical with those of our coast, or have representatives which give 
to the members of that family found on the two sides of the continent 
a striking similarity. Stomobrachium, Zygodactyla, and ^Equorea are 
found both in the Atlantic and Pacific ; we have Rhegmatodes, which 
has as yet no representative on the Pacific coast of North America, 
while Crematostoma has not been found on the Atlantic side. 

This genus recalls Zygodactyla, in having a large digestive cavity ; it 
is, however, much less contractile than in that genus, and hangs always 
far below the level of the circular tube. The actinostome, as in Zygo- 
dactyla, is surrounded by a number of narrow, lanceolate, fimbriated 
lips, one for each chymiferous tube, which are from sixty to eighty in 
number. 

Crematostoma flava A. AGASS. 

Crematostoma flava A. AGASS.; in Agassiz's Cont. Nat. Hist. U. S., IV. p. 360. 1862. 

The lower part of the digestive cavity, immediately above the acti- 
nostome, is alone capable of considerable contraction, the digestive 
cavity hanging down like a large cylindrical sac, with numerous longi- 
tudinal folds extending from the origin of the chymiferous tubes along 
the whole length of the sac to the actinostome. The chymiferous 
tubes are broad, extending a short distance along the projection of the 
spherosome into the cavity of the bell. The ovaries extend the whole 



^EQUOREA. 109 

length of the chymiferous tubes, they are linear (Fig. 159 a ) ; opposite 
each of the chymiferous tubes there is one large tentacle, very con- 
tractile, with a slight swelling at the base ; between the chymifer- 
ous tubes, one smaller tentacle and marginal capsules ; the chymiferous 
tubes, near the base of the Fig . 159 a. 

digestive cavity, anasto- 
mose frequently ; the sec- 
tion of the spherosome re- 
sembles that of Zygodac- 
tyla more than any other 
genus of the family. The 
disk increases rapidly from 
the circular tube, and re- 
mains then of the same 
thickness to the base of 
the projection of the disk 
in the inner cavity ; here 
the outline of the inner 
bell suddenly curves down, 
and projects like a spheri- 
cal segment, nearly hemi- 
spherical, in the cavity of 
the bell, the outline of the 
outer bell having a slight 
constriction at this point, and from there curving gradually to the 
abactinal pole. From three to four inches in diameter ; specimens one 
and a half inches high, measured three and a half inches in diameter. 

Gulf of Georgia, W. T. (A. Agassiz). 

Cat. No. 123, Gulf of Georgia, W. T., June, 1859, A. Agassiz. Medusa. 



^EQUOREA PER. et LES. 

JEquorea PER. et LES. ; in Ann. du Mus., p. 22. 1809. 
JEquorea LESS. (p. p.). Zooph. Acal., p. 305. 1843. 

AGASS. Cont. Nat. Hist. U. S., IV. p. 359. 1862. 




^Equorea ciliata ESCH. 

JEquorea ciliata ESCH. Syst. der Acal., p. 109, PL 9, Fig. 1. 1829. 
JEquorea ciliata AGASS. Cont. Nat. Hist. U. S., IV. p. 359. 1862. 
JEquorca ciliata LESS. Zooph. Acal., p. 306. 1843. 

Northwest Coast of North America, Lai 41 to 51 N. (Eschscholtz) ; 
Straits of Fuca (A. Agassiz). 

Fig. 159 a . Cremates toma flava A. Agass. 



110 



^QUOREA ALBIDA. 



Fig 160. 




.ZEquorea albida A. AGASS. 

JEquorea albida A. AGASS. ; in Agassiz's Cont. Nat. Hist. U. S., IV. p. 359. 1862. 

The genus jEquorea, as generally received, includes species which 
have been separated from it, under the name of Zygodactyla, by 
Brandt, and to which the JEquorea vitrina of Gosse also belongs. The 
long pendent membrane of the digestive cavity, with the actinostome 

surrounded with numerous lanceolate and strongly 
fimbriated folds, at once distinguishes this genus 
from Rhegmatodes, which includes such species as 
Rhegmatodes tenuis and floridanus, and the ^Equorea 
forbesiana of Gosse, in which the chymiferous tubes 
are not numerous, the tentacles few in number, and 
the digestive cavity not capable of extension as in 
Zygodactyla, the lips of the actinostome being short 
and simple folds, ^quorea is distinguished from 
both these genera by having a greater number of 
chymiferous tubes, the ovaries extending for their 
whole length, from the circular tube to the mem- 
brane of the digestive cavity. The tentacles are numerous, the spurs 
at the base of the large tentacles being more closely connected with 
them than in the other genera of this family. The actinostome is a 
simple opening, without appendages such as we find in Zygodactyla, 
Stomobrachium, and others, having only slight indentations formed 
along its margin, giving the opening a somewhat polygonal shape 

(Fig. 160) ; and when entirely 
closed, the edges of the acti- 
nostome meet, forming a slight 
button. The spherosome has a 
slight indentation near the ab- 
actinal pole, the bell diminish- 
ing very gradually in thickness 
towards the circular tube (Fig. 
161) ; the gelatinous disk hardly 
projects into the cavity of the 
bell ; the chymiferous tubes run 
into the digestive cavity at 
their highest point, the radius 
of the digestive cavity being about one third that of the spherosome ; 
the chymiferous tubes are narrow, there are three or four marginal 
tentacles between every two chymiferous tubes, and two or three 

Fig. 160. A portion of the disk of ^Equorea albida, from the abactinal pole. 
Fig. 161. A natural attitude of .Equorea albida. 



Fig. 161. 




JEQUOREA ALBIDA. Ill 

marginal capsules, two for every large tentacle, between the tubes, in 
each of which there are from three to four granules arranged in a 
cluster in the centre ; the capsules are perfectly spherical (c, Fig. 162) ; 
the walls of the tentacles taper very gradually from the circular tube, 
the swelling has but little prominence, and the pigment cells at their 
base are not numerous, scarcely coloring it ; the lasso cells are arranged 
in small knobs, scattered, at some distance from one another, all over 
the surface of the tentacles; the spur of the tentacles (s, Fig. 162) is 
placed directly opposite 
the large tentacle on the 
other side of the circular 
tube ; the walls of this spur 
are thick, and its hollow 
space appears like a small 
elliptical opening when 
seen from above ; the un- 
developed tentacles are solid conical protuberances, from which the 
cavity of the tentacle is little by little hollowed out ; the tentacles are 
usually carried tightly twisted like a corkscrew ; when in motion, the 
tentacles are fully expanded, then bent at right angles and drawn 
inside the veil and slowly thrown out, the tentacles almost closing the 
opening of the cavity of the bell, giving these Medusae the appearance 
of having numerous long tentacles (Fig. 161) arising from a small cir- 
cular tube, the chymiferous tubes and the tentacles in their prolonga- 
tion making almost a complete sphere. Specimens from one to two 
and a half inches in diameter were taken at Naushon during Sep- 
tember. 

Buzzard's Bay, Naushon (A. Agassiz). 

Cat. No. 279, Naushon, Mass., Sept. 1861, A. Agassiz. Medusa. 

Fig. 162. Magnified view of part of the marginal tube, c, capsule ; s, spur of the tentacles, t. 




112 GERYONOPSID^E. 



Family GERYONOPSID^E Agass. 

Geryonopsidce AGASS. Cont. Nat. Hist. U. S., IV. p. 362. 1862. 
Geryonidce ESCH. (p-p-)- Syst. der Acal., p. 86. 1829. 



EIRENE ESCH. 

Eirene ESCH. Syst. der Acal., p. 94. 1829. 
Geryonopsis FORBES. Naked-eyed Medusae, p. 39. 1848. 
Phortis McCR. Gymn. Charl. Harb., p. 90. 
Eirene AGASS. Cont. Nat. Hist. U. S., IV. p. 362. 1862. 



Eirene gibbosa AGASS. 

Eirene gibbosa AGASS. Cont. Nat. Hist. U. S., IV. p. 362. 1862. 
Phortis gibbosa McCR. Gymn. Charl. Harb., p. 91. 

Charleston Harbor (McCrady). 



Eirene ccerulea AGASS. 

Eirene ccerulea AGASS. Cont. Nat. Hist. U. S., IV. p. 362. 1862. 

The spherospme increases rapidly in thickness from the circular tube 
to the peduncle, which tapers quickly, and when fully expanded does 
not reach much beyond the level of the veil (Fig. 163) ; the ovaries 
are linear, slightly convoluted, do not extend the whole length of the 
rig. 1(33 . chymiferous tubes, but begin about half- 

way up, between the circular tube and 
the base of the peduncle, extending close 
to the digestive sac, which is terminated 
by four short lips with slightly fimbriated 
edges ; the outline of the spherosome is 
hemispherical ; the tentacles are numer- 
ous, in the largest specimens measuring 
an inch and a quarter across the disk, 
and an inch in height ; there were as many as thirty to thirty-five 
short tentacles between every two chymiferous tubes ; the gelatinous 
disk has a slight tinge of blue. Found at Key West and the Tortugas 
in April. 

Florida, Key West (L. Agassiz). 




Fig. 163. Eirene ccerulea. 



TIMA. 



113 



TIMA ESCH. 

Tima ESCH. Syst. der Acal., p. 103. 1829. 

Eirene ESCH. (p. p.). Syst. der Acal., p. 94. 1829. 

Dlancea DELLE CH. Mem. sulla Storia e Notomia. 1823-29. 

Tima LESS. Zooph. Acal., p. 333. 1843. 

Tima AGASS. Cont. Nat. Hist. U. S., IV. p. 362. 1862. 



Tima formosa AGASS. 

Tima formosa AGASS. Cont. Nat. Hist. U. S., IV. p. 362. 1862. 

Spherosome greater than a hemisphere, with edges slightly receding 
from the polar axis, near the circular tube. The disk increases in 
thickness very gradually to the bend of the chymiferous tubes (Fig. 
164), where the gelatinous disk extends in a broad cone, slowly dimin- 
ishing in diameter, till it reaches somewhat beyond the level of the veil. 
This peduncle is contractile, extending at times the diameter of the 
inner cavity of the bell beyond the circular tube ; the sexual organs 

Fig. 164. Fig. 165. 





Fig. 166. 




extend from the circular tube (Fig. 165) the whole length of the chy- 
miferous tubes, and nearly to the end of the peduncle ; the four chymif- 
erous tubes open into a short digestive cavity (c, Fig. 166) ; the acti- 
nostome is surrounded by four very slender, long, lanceolate, fimbriated 
lips. (/, Fig. 166.) There are thirty-two long contractile tentacles, 
seven between every two chymiferous tubes, and one opposite each 
tube ; the ovaries consist of series of little pouches hanging clown on 

Fig. 164. Tima formosa, half natural size. 
Fig. 165. Quarter-disk, from the abactinal pole; natural size. 

Fig. 166. Digestive cavity and actinostome. t, termination of chymiferous tube ; c, digestive 
cavity ; /, one of the four fimbriated lips of the actinostome. 

NO. II. 15 



114 



TIMA FORMOSA. 



Fig. 167. 




both sides of the chymiferous tubes (Fig. 167) ; the tentacles have a 
very prominent pouch, strongly compressed laterally, at the 
point of junction with the marginal tubes ; between the 
f larger principal tentacles (t, Fig. 168) we find a number of 
small pouches, rudimentary tentacles (t', Fig. 168), which 
are never developed fully, yet appear to be included in the 
/ regular cycle of tentacles, to judge from the number we 
find at different stages of growth ; between the smaller 
tentacles we find marginal capsules (c, Fig. 168), with four 
to five granules arranged near the periphery ; the circular 
tube is large and very prominent ; the spherosome is per- 
fectly colorless, but the ovaries, as well as the base of the 
tentacles, are of a beautiful milky white, which makes these Jelly- 
fishes a very prominent object in the water ; they do not come near 

the surface, but remain usually 
four or five feet below ; they 
are found during the whole year, 
adult specimens having been taken 
in June, October, December, and 
March. The young Medusa (Fig. 169) differs widely from the adult; 
there are no ovaries in specimens measuring more than an inch in 
diameter ; the chymiferous tubes extend along the short proboscis 
(t, Fig. 170), opening into a digestive cavity, d, which terminates 
with four rather simple lips, more like the actinostome of a Lafoea ; 
there are but three large marginal tentacles between adjoining chy- 
miferous tubes, and no signs of any further cycles of tentacles in 



Fig. 168. 




c t 



Fig. 169. 




Fig. 170. 




the specimen figured here ; marginal capsules were likewise not yet 
developed. The young Medusa of Tima is another case to be added 
to Melicertum, Lafoea, and Atractylis, where there are no marginal 

Fig. 167. Portion of the ovary, f, f, lobes running on either side of the chyraiferous tubes. 
Fig. 168. A magnified portion of the circular tube. /, , principal tentacles ; t', rudimentary 

tentacles ; c, marginal capsules- 
Fig. 169. Young Tima formosa, natural size. 
Fig. 170. Digestive cavity of Fig. 169. /, termination of chymiferous tubes; d, digestive 

cavity. 




TIMA FORMOSA. 115 

capsules along the circular tube, and yet these Medusae have all been 
traced to a Campanularian-like Hydrarium. Tima differs from the 
other genera just mentioned, in developing eventually these marginal 
capsules, which are always wanting, at least in the shape of capsules 
with limestone concretions, in the above-mentioned genera. See the 
magnified portion of the circular tube of Tima (Fig. 168), and compare 
this, crowded with marginal capsules, to the circular tube Fig 171 . 

of Melicertum and Lafoea. Having kept in confinement 
males and females of this species, I succeeded in raising 
from the eggs the Planula, and ultimately the Hydra- 
rium, as in the case of Melicertum, where further details 
will be found concerning the mode of development of 
the Planula into the Hydrarium ; as this is identical in 
both, I shall only describe the Planula and Hydrarium 
as far as they differ from those of the Melicertum. 

The Planula is more pear-shaped (p, Fig. 171) than 
that of the Melicertum, and takes a far greater elongation before at- 
taching itself, (j/, Fig. 171.) The Hydrarium is also more slender, 
the cup is more distinct, the tentacles are quite long and slender, and 
are connected at the base by a Fig . 172 . 

web (Fig. 172) ; this seems to 
be a mere embrvonic feature, as 

J 

I have noticed the same w r eb in 
several young Campanularians. 
The Hydrarium here figured at- 
tained its present features at the 
end of six months. The com- 
munities are very small tufts, 
barely perceptible to the naked 
eye ; they appeared like a few 
slender threads on the side of 
the glass vessel in which the 
Planula was raised ; I did not 
succeed in raising the Hydrarium to observe its further develop- 
ment. 

Massachusetts Bay (L. Agassiz). 

Cat. No. 276, Cape Cod, March, 1862, A. S. Bickmore. Medusa. 

Cat, No. 372, Nahant, September, 1863, A. Agassiz. Medusa. 

Museum Diagram No. 17, after A. Agassiz. 

Fig. 171. p, young planula ; p 1 , planula immediately before attaching itself. 
Fig. 172. Single Hydra of the tuft of a Tima Hydrarium, greatly magnified. 




116 EUTIMA. 



EUTIMA McCR. 

Eutima McCR. Gymn. Charl. Harbor, p. 87. 

Eutima AGASS. Cont. Nat. Hist. U. S., IV. p. 363. 1862. 



Eutima mira McCR. 

Eutima mira McCR. Gymn. Charl. Harb., p. 88, PL 11, Figs. 8, 9. 
Eutima mira AGASS. Cont. Nat. Hist. U. S., IV. p. 3G3. 1862. 

Charleston, S. C. (McCrady). 



Eutima variabilis McCu. 

Eutima variabilis McCR. Gymn. Charl. Harb., p. 88. 

Eutima variabilis AGASS. Cont. Nat. Hist. U. S., IV. p. 363. 1862. 

Charleston, S. C. (McCracly). 



Eutima limpida A. AGASS. 

Eutima limpida A. AGASS.; in Agassiz's Cont. Nat. Hist. U. S., IV. p. 363. 1862. 

This species (Fig. 173) resembles closely the Eutima mira of 
Charleston Harbor ; like it, it has only four long tentacles (with one 
short cirrus on each side of the tentacle, Fig. 176), one opposite each 
chymiferous tube, two large marginal capsules between each two ten- 

Fig- 1<3. Fig. 174. 





tacles (Fig. 174), arranged at equal distances round the marginal tube, 
and a number of rudimentary tentacles which are never further devel- 
oped. The gelatinous part of the disk, which projects in the proboscis 
(^/, Fig. 175), is shorter than in the Charleston species; it does not 
extend much more than the height of the bell beyond the level of the 
veil ; the tentacles also are shorter, and have no swelling ; the diges- 

Fig. 173. Profile of Eutima limpida, reduced in size. 
Fig. 174. Quarter-disk of Fig. 173. 



EUTIMA LIMPIDA. 



117 



live cavity (c, Fig. 175) is very short; it is situated at the extremity 
of the narrow flexible sac, extending from cj to c, Fig. 175, and termi- 
nates in a flat quadrangular disk (d, Fig. 175), which is sometimes 
folded in the shape of forceps, although generally kept stretched out 
flat, like the sucking disk of a leech ; in the centre of this disk we find 
the actinostome, which is a very small rosette-shaped opening, with 
four loops. The genital glands (o, Fig. 175) are narrow; they rise 
almost from the circular tube, and follow the chymiferous tubes along 




Fig. 176. 




Fig. 177. 



Fig. 178. 





the gelatinous prolongation of the disk, nearly to the level of the veil. 
(o', Fig. 175.) The tentacles are hollow and have no swelling at the 
base (Fig. 176), the walls being thicker and tapering gradually to the 
extremity. In the marginal capsules (Fig. 177), which are so large 
that they can be seen with the naked eye, there are from twelve to 
thirteen granules arranged in a circle near the periphery of the capsule. 
The rudimentary tentacles (t, Fig. 178) are mere triangular expansions 

Fig. 1 75. Magnified view of the proboscis and genital organs. g, terminal point of gelatinous 
prolongation of the disk ; o, part of genital organs extending along the bell ; o', terminal point of 
genital organs along the gelatinous prolongation of the bell ; c, digestive cavity ; d, actinostouie in 
its usual mode of expansion. 

Fig. 176. Magnified portion of the circular canal, with a primary tentacle and tentacular cirri, 
to show the rudimentary tentacles between the chymiferous tubes and the capsules, c. 

Fig. 177. Magnified marginal capsule, showing the circular arrangement of the granules. 

Fig. 178. Still more magnified view of tho rudimentary tentacles, c, circular tube ; ^rudi- 
mentary tentacles. 



118 POLYORCHIDJE. 

of the circular tube, c. The bell widens very rapidly towards the lower 
floor, and is perfectly transparent ; the ovaries, as Avell as the tentacles 
and the proboscis, are colorless ; the diameter of the bell is nearly two 
inches, and the polar diameter about half an inch ; the proboscis is usu- 
ally carried as in Fig. 173, and, as the digestive cavity is capable of but 
slight contraction, it bears usually the proportions of that figure to the 
diameter of the bell. Found in Buzzard's Bay during September. 
Buzzard's Bay, Naushon (A. Agassiz). 



Eutima pyramidalis AGASS. 

Eutlma pyrarnidalis AGASS. Cont. Nat. Hist. U. S., IV. p. 363. 1862. 

The spherosome is hemispherical, and more heavy than in either 
Eutima Umpida or E. mira ; the proboscis is shorter, and tapers rap- 
idly ; the tentacles are short ; the oral leaflets are rounded and sepa- 
rated by an indentation from one another, the edge of the leaflets being 
finely scalloped ; the digestive cavity is short. 

Florida, Key West (L. Agassiz). 



Family POLYORCHID^E A. Agass. 

Pobjorclddce A. AGASS. ; in Agassiz's Cont. Nat. Hist. U. S., IV. p. 349. 1862. 

This family is characterized by the peculiar structure of the chymif- 
erous tubes, which, sending off diverticula at right angles to the main 
tube, give these Meduste a very peculiar aspect: With the exception 
of Polyorchis, we know of only one other genus, Olindias Fr. Mull., 
which has the same structure of the chymiferous tubes. Miiller, at the 
close of his description of 0. sambaquiensis, says it is characteristic of 
the uncertainty which still exists in the classification of Acalephae, that 
the attempt to assign to this Medusa its position in the systems of Esch- 
scholtz, Forbes, or Liitken, places them in families with which they have 
no affinities, and we cannot even assign them to any of the families of 
Gegenbaur ; the only genus to which it seems to have any relation is 
Melicertum Oken. This suggestion of Miiller, as to the affinities of his 
genus Olindias, is fully borne out by the examination of the Melicertum 
2iemcillatum of Eschscholtz, which has, like it, peculiar chymiferous 
tubes, and also the discovery of Gonionemus, a genus having the gen- 
eral appearance of Olindias without the ramifying chymiferous tubes. 
Gonionemus shows us the close relation that exists between these 
genera and Melicertum, although the differences existing between 
Olindias and Polyorchis on one side, and Gonionemus and Melicertum 
on the other, are such as to form very natural families. 



N 



POLYORCHIS. 



119 



POLYORCHIS A. AGASS. 

Polyorchis A. AGASS.; in Agassiz's Cont. Nat. Hist. U. S., IV. p. 349. 1862. 
Mdicertwn Escu. (p.]).). Syst. der Acal., p. 105. 1829. 



Polyorchis penicillata A. AGASS. 

Polyorchis penicillata A. AGASS. ; in Agassiz's Cont. Nat. Hist. U. S., IV. p. 349. 1862. 
Melicertum penicillatum ESCH. Syst. der Acal., p. 106, PL 8, Fig. 4. 1829. 
At/laura penicillata EL. Man. d'Actinol., PI. 33, Fig. 4. 
Melicertum penicillata LESS. Zooph. Acal., p. 293. 1843. 



This strange Jelly-fish I first found in 
great numbers, while becalmed at the 
entrance of the Straits of San Juan de 
Fuca, in October, in company with large 
numbers of a Medusa which I suppose to 
be the Mesonema (Zyyodactyla) ccerules- 
cens found b}^ Brandt in the latitude of 
San Francisco, and which I had after- 
wards occasion to observe again near 
Punta de los Reyes, about twenty miles 
northwest of San Francisco. It is also 
quite common in the harbor of San Fran- 
cisco during the winter months. It com- 
bines the characters of several families, 
has the long, pendent digestive cavity 
of the Thaumantiadae (Fig. 179) ; the 
ovaries hang independently, 
four in number to each chy- 
miferous tube (Fig. 180), 
near the base of the diges- 
tive cavity, as in the Tra- 
chynemidos. But what is 
very peculiar is the struc- 
ture of the chymiferous 
tubes ; instead of being sim- 
ple or forking tubes, as we generally 
find in the Hydroids, they remind us of 
the structure of the chymiferous tubes in 
Idyia, sending off short shoots into the 
gelatinous disk at right angles, alternat- 

Fig. 1 79. A profile view, somewhat magnified, of 
Polyorchis penicillata. 

Fig. 180. Ovaries of one of the chymiferous tubes. 



Fig. 179. 



Fig. 180. 





120 POLYORCHIS PENICILLATA. 

ing with each other (Fig. 179) ; this gives to these Medusae a very 
peculiar appearance, differing entirely from any other family of Hy- 
droids, and for which I would propose the name of Polyorchidae. The 
rig. isi. polar axis is the longest ; the spherosome has its greatest 
width at the level of the ovaries (Fig. 179) ; from this 
point it turns rapidly towards the abactinal pole, while it 
scarcely tapers towards the actinostome, giving the sphero- 
some the appearance of a cylinder with a rounded top ; 
the thickness of the spherosome is very uniform, projecting 
but slightly in the inner cavity of the bell (Fig. 181), at 
the point of attachment of the digestive cavity ; the diges- 
tive cavity is long, slender, and exceedingly movable, terminating in 
four lobes (Fig. 182), and extending to the opening of the veil; there 
are four genital organs of unequal length, attached at the highest point 
(Fig. 180) of the four chymiferous tubes, hanging freely in the cavity 
of the bell ; they are arranged one behind the other, along the upper 
extremity of the chymiferous tubes, the longest equalling half the 
height of the inner bell. The diverticula from the main tubes com- 
mence immediately at the base of the ovaries, where they are quite 
small ; they gradually increase in size for about half the length of the 
chymiferous tubes, whence they continue nearly of the same size to the 

Fig. 182 Fig. 183. 






circular tube ; the offshoots are somewhat more numerous in the lower 
part of the tube. (Fig. 179.) The tentacles are very contractile (com- 
pare Figs. 183 and 179) ; when drawn up, they are scarcely half the 
length of the spherosome ; they project horizontally from the chymif- 
erous tubes for a short distance, and from the point where a conical 
dark-purple ocellus is placed are then bent at right angles to their 
former direction ; it is only the lower part of the tentacle which is 
capable of expansion ; when the tentacles are fully expanded, they 
extend three or four times the length of the bell. The genital sacs, 
the chymiferous tubes, the tentacles, and the digestive cavity, are of a 

Fig. 181. Section of the bell. 

Fig. 182. Part of the disk of Fig. 179, seen from the abaotinal pole. 

Fig. 183. Two of the marginal tentacles in a contracted state. 



LAODICEID^E. 

light reddish-brown color ; the bell has a yellowish tint. The motions 
of this Medusa are rather sluggish ; they are very conspicuous in the 
water on account of their wreath of dark-purple ocelli ; they are grega- 
rious, move near the top of the water, the bell almost striking the 
surface, and when disturbed return to the surface immediately. There 
are thirty-six tentacles, eight between each of the four chymiferous 
tubes, and one at the base of each tube ; the four lobes of the actinos- 
torne are long, and flare out considerably beyond the diameter of the 
digestive cavity, which is of a uniform length, widening very gradually 
to the point of junction with the chymiferous tubes ; the main chymif- 
erous tubes are slightly winding ; the lower knotty, club-shaped diver- 
ticula have a tendency to bend downwards towards the circular tube ; 
the veil is narrow ; the ovaries are one third the length of the sphero- 
some. These Jelly-fishes attain a height of nearly two inches ; but 
smaller specimens, measuring only an inch in height, showed, except 
the size, no differences ; the character of the marginal capsules of this 
Medusa, if there are any, has not been examined. 

This is undoubtedly the Melicertum penidllatum of Eschscholtz, 
though from his description and figures the characteristic features of 
this Medusa are not very evident. 

California (Eschscholtz) ; Gulf of Georgia (A. Agassiz) ; San Fran- 
cisco, Cal. (A. Agassiz). 

Cat. No. 283, San Francisco, Cal., Dec. 1859, A. Agassiz. Medusa. 

Cat. No. 284, San Francisco, Cal., Jan. 1854, T. G. Cary. Medusa. 

Cat. No. 285, Gulf of Georgia, W. T., 1859, A. Agassiz. Medusa. 



Family LAODICEID^E Agass. (emend. A. AGASS.). 

Laodiceiilce AGASS. Cont. Nat. Hist. U. S., IV. p. 350. 1862. 
Thaumantiadce GEGEXB. ; in Zeit. f. Wiss. Zool., p. 236. 1856. 

The family name of Laodiceidaa given to the Thaumantiadae Gegenb. 
by Professor Agassiz, may, in its turn, yield to that of Lafoeadaa, should 
it be found that the Hydrarium of Laodicea Less, is invariably a Lafcea. 
The name Laodiceida3 is here retained, as the Medusas, associated under 
that generic name, present differences which, when the Hydrarium be- 
comes known, may warrant our retaining the name Laodicea for some 
of them, and thus the genus which has given the family name may 
still be retained, even if for the present we substitute for some of the 
species of Laodicea the older name of Lafoea of Lamouroux. The 
Laodiceidas are here extended to include the Melicertidse, which cer- 
tainly are closely related, and can hardly be divided into distinct fami- 
lies, if we are to judge from the young Medusae and the Hydrarium of 
these genera. 

NO. II. 16 



122 LAFCEA. 



LAFCEA LAMX. 

Lafcea LAMX. Expos. Meth. 1812. 

Lafcea AGASS. Cont. Nat. Hist. U. S., IV. p. 351. 1862. 

Lafcea A. AGASS. ; in Proc. Bost. Soc. Nat. Hist., IX. p. 91. 

Atractylis WRIGHT ; in Ann. & Mag., VIII. p. 129. 1861. 

Campanulina VAN BEN.; in Bull. Acacl. de Belg., XIV. No. 5. 1847. 

Laodicea AGASS. (p.p. non Less.). Cont. Nat. Hist. U. S., IV. p. 350. 1862. 



Laicca calcarata A. AGASS. 

Laodicea calcarata A. AGASS.; in Agassiz's Cont. Nat. Hist. U. S., IV. p. 350. 1862. 
Lafxa cornuta AGASS. (non Lamx.). Cont. Nat. Hist. U. S., IV. p. 351. 1861. 
Campanularia dumosa LEIDY. Mar. Inv. N. J. and R. I., p. 6. 
Lafcea cornuta A. AGASS. ; in Proc. Bost. Soc. Nat. Hist., IX. p. 91, Fig. 4. 

The Medusa of Lafoea described in the Contributions of Professor 
Agassiz, Vol. IV. p. 3-51, was referred by him to Lafcea cornuta of 
Lamouroux. Having, however, since that time found at Nahant a 
young Medusa closely allied to the one to be here described, I am 
inclined to doubt this identification, even though I have not observed 
its Hydrarium, as I have done for the Lafcea of Naushon ; the absence 
of pigment-spots at the base of the tentacles, and the different number 
of tentacles at the time when the Fig . 1S4 . 

Medusa? are liberated from the repro- 
ductive calycles, easily distinguishes 
these two Medusa?. The Lafoean Me- 
dusa found at Naushon was also fol- 
lowed in its more advanced stages, 
till we could connect it with the 
young of the Medusa before described 
as Laodicea calcarata. 

The largest specimens observed 
were an inch in diameter ; the bell 
is perfectly transparent (Fig. 184), 
and, were it not for the four dark- 
yellowish ovaries, it would readily 
escape notice ; they hang down like 
short curtains in close folds, extend- 
ing almost the whole length of the 
chymiferous tubes, from the digestive cavity where they run into the 
folds of its base (Fig. 185), to the circular tube ; the digestive cavity 
is short, and the actinostome divides into four thin, convoluted folds, 
projecting beyond the edge of the digestive cavity to twice its diarn- 

Fig. 184. Adult Medusa of Lafcea calcarata ; magnified. 




LAFCEA CALCARATA. 



123 



eter (Fig. 186) ; the chymiferous tubes are narrow ; the tentacles have 
their greatest diameter directly at the circular tube ; they are, how- 
ever, unequally developed, and vary greatly in character. The large 
tentacles are very contractile ; near the base they have a swelling 
which consists of small granular cells, with a spot of dark-violet pig- 
ment-cells on its lower surface (Fig. 187) ; on the opposite side of this 
bulb we find a spur-like projection (see t, Fig. 187), consisting of large, 
transparent, polygonal cells ; from this point the tentacle tapers very 
gradually, and is also made up of larger cells than the basal swelling ; 



Fig. 185. 



Fig. 186. 





these cells are arranged in two rows, and through them runs a thin 
tube to the tip of the tentacle ; the lasso cells are numerous, and run 
in a zigzag manner all over the surface of the large tentacles. When 
new tentacles are formed in the adult Medusae, it is the spur which is 
first developed, and afterwards the swelling with the pigment-cells ; the 
tentacle has then a triangular appearance, and is turned in the opposite 
direction from the spur ; from this time it lengthens very rapidly, though 
many of the tentacles are never fully developed. There are besides 
long thread-like tentacles, which are not hollow, and are exceedingly 




Fig. 133. 




contractile (c, Fig. 187) ; in adult specimens they are not distributed 
regularly, but in young specimens of a quarter of an inch in diameter, 
having not more than sixteen large tentacles, and sixteen smaller ones 
(like the large ones) placed between them, we find on the side of each 
of these sixteen larger tentacles one of these cirri (Fig. 194) ; but as 
the number of tentacles increases, the cirri are not formed with the 
same regularity. We find still a third kind of tentacle : club-shaped 

Fig. 185. One of the ovaries and the actinostome. 
Fig. 186. Actinostome, actinal view. 

Fig. 187. Magnified view of a portion of the circular tube, t, one of the large tentacles, with 
spur and pigment-cells ; c, one of the cirri ; , club-shaped appendage. 

Fig. 188. Actinostome and rudimentary ovaries of young Medusa, seen in profde. 



124 



LAFCEA CALCARATA. 



Fig. 189. 




appendages (&, Fig. 187) made up of large polygonal cells, perfectly 
transparent, one or two sometimes placed between each of the larger 
tentacles. The large tentacles have the same color as the ovaries. 
The young Medusa? differ from the adult in the extent of the ovaries, 
which are limited to the upper part of the chymiferous tubes, close 
to the digestive cavity (Fig. 188) ; the ovaries gradually extend 
further towards the circular tube as they grow older ; the digestive 
cavity is a simple cylinder pressed in, forming small lips ; the tentacles 
also, as described above, are less numerous. The adult Medusa is very 

active, moving with great ra- 
pidity, by drawing its tentacles 
into the bell, throwing them 
out again with violence, and 
allowing itself to be carried 
along by the momentum it has 
acquired; twisting its tentacles 
during that time, and spread- 
ing them in every conceivable 
manner. When it is lazily car- 
ried along, the bell often assumes strange attitudes ; the thick upper 
part of the disk becomes rounded, and the thin portion of the umbrella 
is projected beyond it, like the rim of a four-cornered ha.t. (Fig. 189.) 
At other times it seems as if the umbrella had been tied in the middle, 
the upper and lower part of the disk almost joining in the middle at an 
obtuse angle. The next moment the disk becomes perfectly flat, the 
tentacles are drawn up in close knots or shortly-twisted coils, so that it 
scarcely seems to be the same animal, which in a moment assumes 
again a globular shape, and darts off to go through the same changes 
of form. 

The Medusa in its youngest stage resembles closely the figure given 
by Wright of the Medusa of A. repens in the Edinburgh Philosophical 
Journal. The Hydromedusarium differs so much, that it does not seem 

to belong to the same genus as 
the English species ; it is found 
growing along the stems of a 
species of Dynamena, found 
just below the line of low- 
water-mark. The individuals 
are arranged, in a quincunx manner, on both sides of a long, slender, 
creeping stem, which does not branch. It resembles a true Campanu- 
laria in having a transparent bell disconnected from the stem. Other- 
Fig. 189. Different attitude of the Medusa of Fig. 184. 

Fig. 1 90. Hydrarium of Lafcea calcarata ; the extremity of the reproductive calycle is some- 
what injured. See Fig. 191. 



Fig. 190. 




LAFCEA CALCARATA. 125 

wise the sterile Hydra reminds us of a true Sertularian, with a few 
thick tentacles, and a long digestive cavity, capable of great expansion. 
The bell is attached to the stolon by a short stem, a mere bend in its 
lower portion, so that the sterile individuals are set off a short distance 
from the main stem. (Fig. 190.) The reproductive calycles are gigan- 
tic, compared to the size of the sterile individuals. (Fig. 190.) They 
are few in number, not more than two or three to a stem, Fig . 19 i. 
and resemble those of L. amphora ; only one or two Me- 
dusa? are developed simultaneously, the more advanced 
one filling the cavity of the capsule almost entirely. 
(Figs. 190, 191.) The sterile individuals recall the Tubu- 
larians, as do in fact all the Sertularians, in which the 
connection between the bell of the sterile individuals and 
the digestive cavity is not as intimate as in the true 
Campanula rians, giving us at the same time a measure 
of the embryonic standing of the Tubularians, the Sertu- 
larians, and the Campanularians ; the Medusa? of this 
Sertularian-like Hydromedusarium resemble more those 
of the Tubularians than those of the Campanularians. The vertical 
diameter of the Medusa is greater than the transverse ; the bell is of 
moderate thickness, the abactinal part being slightly conical (Fig. 192) ; 
the digestive cavity is short, and consists of four simple lobes, giving 
the actinostome the shape of a cross. When it escapes from the repro- 
ductive calycle, it has only two long tentacles, two slightly developed 

Fig. 192. Fig. 193. 






ones, and four more hardly perceptible in the middle of the space 
between the four chymiferous tubes (Fig. 193) ; at the base of all the 
tentacles, and over the whole surface of the digestive cavity, we find 
large yellow cells scattered irregularly ; the long tentacles are highly 
contractile ; a spiral of lasso cells, diminishing in size, and beginning at 
a small distance from the sensitive bulb, winds round the tentacles j 

Fig. 191. Uninjured reproductive calycle. 

Fig. 192. Medusa immediately after its escape from the reproductive calycle. 

Fig. 193. A Medusa somewhat more advanced, from the abactinal pole. 




126 LAFGEA DUMOSA. 

at the base of the tentacles the walls are thick, and the sensitive 
swelling quite prominent, having a dark pigment-spot. The Medusa, 
when it escapes from the reproductive calycle, has a vertical diameter 
of about one twentieth to one sixteenth of an inch ; the Hydromedu- 
sarium is from a quarter to an inch long. 

In the next stage observed (Fig. 104) we find the rudimentary ten- 
tacles of the previous stage fully developed, and at the same time the 
thread-like cirri of the adult Lafcea. This stage is important, connect- 
Fi g . 194. ing as it does, without any doubt, two Medusce 

which had thus far been placed in different 
genera. The digestive cavity and the ova- 
ries are nearly in the same condition as that 
observed in young Medusa?, where the spur 
and the different kinds of marginal appen- 
dages were as well developed as in the adult ; 
we have as yet, however, in the present 
stage (Fig. 194), no trace of the spur or of 
the club-like appendages of the circular tube found in the adult. 
These club-like appendages of Lafcea and of Ptychogena show that 
the marginal capsules, the compound eyes, the cirri, and the different 
rudimentary appendages, are only modified tentacles. 
Buzzard's Bay, Naushon (A. Agassiz). 

Cat. No. 151, Naushon, 1861, A. Agassiz. Hydromedusarium. 
Cat. No. 271, Naushon, 1861, A. Agassiz. Medusa. 
Cat. No. 438, Naushon, 1864, A. Agassiz. Medusa. 



Lafcea cornuta LAMX. 

Lafcea cornuta LAMX. Expos. Method. 1812. 

Newfoundland (Lamouroux). 

Lafcea dumosa SARS. 

Lafuza dumosa SARS ; in Vidensk. Forh. 1862. 
Campanularia dumosa JOHNST. Brit. Zooph. 1838. 

Massachusetts Bay (A. Agassiz). Medusa. 

Cat. No. 433, Sea-Coal Bay, N. S., Anticosti Expedition, 1861. Hy- 
drarium. 

Fig. 194. Young Medusa still further advanced than Fig. 193. 



LAODICEA. 127 



LAODICEA LESS. 

Laodicea LESS. Zooph. Aeal., p. 294. 1843. 
Laodicca AGASS. Cont, Nat, Hist. U. S., IV. p. 350. 1862. 
Cosmetira FORBES. Brit. Naked-eyed Medusae, p. 42. 1848. 
Thaumantias GEGEXB. (non Esch.) ; in Zeit. f. W. Zool., p. 237. 1856. 



Laodicea cellularia A. AGASS. 

Laodicea cellularia A. AGASS. ; in Agassiz's Cont. Nat. Hist. U. S., IV. p. 350. 1862. 

I am somewhat doubtful whether this species (Fig. 195) belongs to 
the genus Laodicea, as the examination of the tentacles could not be 
made sufficiently accurate to determine this point. The general form 

Fig. 195 Fig. 196. 

c d 





of the ovaries, however, is the same, beginning at the digestive cavity, 
and running in the form of small hanging lobes along the chymiferous 
tubes, close to the circular tube. The digestive cavity is so short that 
the edge, which extends in the shape of four long, narrow lips, deeply 
frilled (Fig. 196), seems the continuation of the chymiferous tubes, 
reminding us somewhat of the structure of the actinostorne of the 
JEquoridre, as in Stomobrachium. The epithelial cells are large, irreg- 
ular, and hexagonal, and can easily be seen with the naked eye. The 
color of the spherosome is light violet, the ovaries and digestive cavity 
being of a darker color, and the base of the circular tentacles of a still 
stronger shade. There are about twenty-four tentacles between each 
of the four chymiferous tubes, and a tentacle opposite each tube. Found 
in the Gulf of Georgia and at Port Townsend, from July to September. 

Gulf of Georgia, W. T. (A. Agassiz). 

Cat. No. 270, Gulf of Georgia, W. T. ? 1859, A. Agassiz. Medusa. 

Fig. 195. Laodicea cellularia. 

Fig. 196. One of the lips of the actinostome. c, r, c, c, termination of the chymiferous tubes 
into the digestive cavity, d : I, fold of the actinostorae connecting the lips of the actinostome. 



128 MEL1CERTIDJE. 

COSMETIRA FORBES. 

A remarkable Hydroid Medusa, belonging to the genus Cosunetira of 
Forbes, was brought home by the Anticosti Expedition. 
Magdalen Islands, Gulf of St. Lawrence. 
Cat. No. 371, Magdalen Islands, N. S., Anticosti Expedition. Medusa. 



Family MELICERTID^E Agass. 

Melicertidce AGASS. Cont. Nat. Hist. U. S., IV. p. 349. 1862. 

GONIONEMUS A. AGASS. 

Gonionemus A. AGASS. ; in Agassiz's Cont. Nat. Hist. U. S., IV. p. 350. 1862. 

Gonionemus has a general resemblance to Melicertum, but differs 
from it by the shape of the ovaries and of the spherosome. The 
spherosome is an oblate half-spheroid, cut from pole to pole ; the ova- 
ries are in lobes alternating on the sides of the chymiferous tubes, and 
extending their whole length, from the digestive cavity to the circular 
tube ; the digestive cavity is long, and very flexible ; the tentacles are 
numerous, large, and exceedingly contractile ; chymiferous tubes four 
in number. 

Gonionemus vertens A. AGASS. 

Gonionemus vertens A. AGASS. ; in Agassiz's Cont. Nat. Hist. U. S., IV. p. 350. 1862. 

This Medusa was quite commonly found during the month of July, 
swimming in patches of kelp. It at once attracted my attention by 
its peculiar mode of moving. I could see these Jelly-fishes, with the 
tentacles spread out to their fullest extent, sinking slowly to the bot- 
tom, the disk turned downward ; the moment a blade of kelp touches 
the disk, they stop, bend their tentacles like knees, and remain at- 
tached to the sea-weed by means of their lasso cells (Fig. 197), which 
are arranged in rings scattered thickly over the surface of the ten- 
tacles ; after remaining attached in this w r ay a moment, with their 
tentacles extended and mouth turned upwards, they suddenly let go 
their hold, turn upside down, contract their tentacles (Fig. 198) to a 
third of their former length, and begin their upward movements by 
means of short, rapid jerks, given by the sudden expanding and con- 
tracting of the tentacles as they are violently thrown out from the 
cavity covered by the veil. They keep up this rapid motion until they 
reach the surface of the water ; at the instant the upper part of the 



GONIONEMUS VERTENS. 



129 



disk touches the top of the water, the Medusa inverts itself, and sinks, 
with its tentacles fully expanded, until it reaches the bottom, or an- 
other piece of sea-weed, where it attaches itself, and after remaining 
suspended a little while, repeats the same operation ; when attached, 
it requires strength enough to break the tentacles to make them loose 



Fig. 197. 




Fig. 198. 



their hold. I have never found single individuals, but have always 
seen them in large numbers swimming among the sea-weed in the 
manner described. The form of the spherosome is that of an oblate 
spheroid, cut in two by a plane passing through the north and south 
poles, the plane of intersection containing the circular tube ; there are 
sixty-four tentacles, fifteen between each chymiferous tube, placed so 
closely together that they seem all to unite at the 
base. The tentacles, when contracted, resemble a 
scythe fastened by a band to the circular tube 
(Fig. 199) ; the pigmen1>cells are numerous, and 
give the circular tube the appearance of having 
a large row of violet knobs, to which the tentacles 
are attached. There is one part of the tentacle, 
near the tip, which seems to be more thickly cov- 
ered by lasso-cells, and by which the Jelly-fishes 
attach themselves ; when the tentacles are fully 
expanded, they always make an angle at that point, as if they had 
been broken, and the parts joined together again. (Fig. 197.) The 

Fig. 197. Gonionemus vertens, as it appears when attached by its tentacles. 
Fig. 198. Gonionemus vertens, in motion ; natural size. 
NO. II. 17 




130 MELICERTUM. 

ovaries are frill-like lobes (Fig. 200), passing from one side to the other 
of the chymiferous canal ; the chymiferous tubes are slender, and ap- 
pear like four dark-violet threads, connecting the different lobes of the 

Fig. 201. 

I 

Fig. 200. 



Fig. 199. 






ovaries. (Fig. 201.) The digestive cavity reaches about two thirds of 
the length of the chymiferous tubes ; it is very flexible, but scarcely 
contractile (Fig. 201), ending in four large lobes, capable of extend- 
ing for beyond the main wall of the digestive cavity ; the veil is large, 
leaving an opening of half the diameter across the circular tube. 

Gulf of Georgia, W. T. (A. Agassiz). 

Cat. No. 286, Gulf of Georgia, W. T., 1859, A. Agassiz. 

MELICERTUM OKEN. 

Melicertum OKEX. Lehrb. der Nature. 1816. 

C* 

Melicertum AGASS. Cont. Nat. Hist. U. S., IV. p. 349. 18G2. 
Melicerta PER. et LES. (p. p.) ; in Ann. du Mus., XIV. p. 40. 1809. 
Campandla LESS, (non Bl.). Zooph. Acal., p. 281. 1843. 
Stomobrachium FORBES (non Br.). Naked-eyed Medusae, p. 30. 1848. 

Melicertum campanula ESCH. 

Melicertum campanula ESCH. Syst. der Acal., p. 105. 1829. 

Melicertum campanula AGASS. Cont. Nat. Hist. U. S., IV. p. 349. 1862. 

Melicertum campanula A. AGASS.; in Proc. Bost. Soc. Nat. Hist., IX. p. 96, Figs. 18, 19. 

Melicerta campanula PER. ct LES.; in Ann. du Mus., p. 40. 1809. 

Medusa campanula FAB. Fauna Gvbnlandica. 1 780. No. 360. 

Medusa campanulata Bosc. Hist. Nat. d. Vers., H. p. 170. 

Campandla Fabricii LESS. Zooph. Acal., p. 281. 1843. 

Campanella campanula MORCH ; in Beskriv. af Gronland, p. 95. 1857. 

This Medusa, first mentioned by Fabricius, has, like many others so 
characteristically described by him, escaped notice entirely, till it was 

Fig. 199. The bend of a contracted tentacle. 

Fig. 200. A portion of the genital organs. 

Fig. 201. One chymiferous tube and half of the digestive cavity. 



MELICERTUM CAMPANULA. 



131 



Fig. 202. 



observed on the coast of New England. Undoubtedly a few others of 
the Jelly-fishes he has enumerated will prove identical with species 
since described, on the coast of England and on our own shores. A 
Medusa of this same genus w r as figured and described by Forbes under 
the name of Stomobrachium octocostatum ; from the figure of Forbes 
it is evidently not a Stomobrachium, and is probably this same Medusa 
which he found in the North of Scotland. Fig. 202 is a profile view, 
natural size, of the Melicertum, one of the most common of our naked- 
eyed Medusae. In the fall, at the time of spawning, it literally swarms 
at the surface, and on sunny days seems particularly to delight to 
come to the surface, where it remains in the afternoon until dark, 
being one of the few Medusa? 
(Zyyodactyla groenlandica has 
the same habit) which are to 
be met with in the after- 
noon. The genus Melicertum 
is closely related to the /Equo- 
rida?, by the number of its 
radiating tubes (of which there 
are eight), and to Staurophora, 
by the blending of the genital 
organs with the actinostome, 
and the total absence of mar- 
ginal bodies, such as capsules, 
cirri, and so forth. If the 
small Medusae here figured 
(Figs. 203, 204) are in reality 
the young of Melicertum, 
Melicertum being the only 
Medusa allied to Staurophora 
w r hich has no eye-specks, the close affinity between them is still 
more strongly marked in the young of these two genera, which can 
only be distinguished from one another by the presence or absence 
of eye-specks. 

From an examination of the Medusa of Lafoea calcarata., I had 
already come to the conclusion that the young Medusa was nearly 
related to Staurophora and Melicertum. Having succeeded in finding 
another Medusa evidently closely allied to it, I was not surprised in 
recognizing a Melicertum of younger stage than any which I had 
observed before. With the stage represented in Fig. 205, which has 
been traced until there could be no doubt as to the genus to which 
the young Medusa belonged, I was sufficiently familiar, from its frequent 
occurrence in the latter part of the spring, to recognize at once in 

Fig. 202. Profile of Melicertum campanula, natural size. 




132 



MELICERTUM CAMPANULA. 



Fig. 203 only a somewhat younger form of the same Medusa,. We 
have thus established, by the observation of this Medusa, as well as 
from the young Hydrarium of Melicertum and Lafoea, the probable 
character of the Hydrarium from which Melicertum, Staurophora, and 
those Medusas which have no marginal capsules, are developed ; show- 
ing that they hold an intermediate position between the Campanu- 



Fig. 203. 



Fig. 204. 





Fig. 205. 



larians and the Tubularians, being more closely allied to the latter in 
their embryonic condition, and assuming as adult Medusae somewhat the 
aspect of Campanularian Medusas. The Trichydra pudica of Wright 
is also closely allied to Lafoea and Staurophora. In the young Medusa 
we have at first only two primary tentacles (Fig. 204) and two rudi- 
mentary ones, and in the next stage there are sixteen. (Fig. 205.) 

The presence of eye-specks at the base of the tentacles of the young 
Medusae of Lafoea calcarata and of Staurophora laciniata are the surest 
means of distinguishing them with accuracy. The differences in the 

shape of the bell between these youngest 
Medusae (Fig. 203) and somewhat older 
stages (Fig. 205), are of a similar character 
to those w r e are familiar with among the 
young Campanularian Medusae of other gen- 
era. To judge from analogy, I strongly sus- 
pect that the young Medusa of Staurophora 
will in its turn be a Medusa, similar to these 
Lafoean forms, having at first but two primary tentacles. In the next 

Fig. '203. Profile view of very young Medusa of Melicertum campanula ; Lafoean like. See 
Fig. 192. 

Fig. 204. Half the disk of the same, seen from the actinal pole. 

Fig. 205. Young Melicertum, -with only four completely formed chymiferous tubes. lc, first 
set of chymiferous tubes ; 2c, second set ; 1, 2, 3, tentacles of the first, second, and third sets. 




MELICERTUM CAMPANULA. 



133 



stage (Fig. 205), which is undoubtedly a young Melicertum, we find 
the second set of four chymiferous tubes developing (2 C , Fig. 205) ; 
they arise, as in the JEquoridse, from the digestive cavity, and extend 
towards the circular tube ; there are at this stage sixteen tentacles, 
usually carried curled up, as in the accompanying figure. I have not 
seen the young Melicertum in stages intermediate between those 
slightly more advanced than Fig. 205, and when they are fully devel- 
oped, as in Fig. 202, where the genital organs extend to the circular 
tube, and the marginal tentacles have become exceedingly numerous. 



Fig. 206. 



Fig. 207. 





Fig. 203. 




Fij*. 209. 



The spherosome is regularly bell-shaped ; it is capable of very varied 
expansion and contraction, appearing at some times almost rectangular, 
then as if tied in the middle, swelling at both poles, again flaring at 
the abactinal extremity, and strongly contracted at the circular tube, 
or flattened like a quoit. The tentacles may expand several times the 
polar diameter of the bell, or contract, by curling close to the circular 
tube. The bell is of a light ochre color ; the genital organs, as well 
as the base of the tentacles, are of a darker shade. When seen from 
above (as Fig. 206), the radiating tubes open 
into a sort of cavity, as in the -/Equoridte, the 
folds of one genital organ extending across to the 
next, as seen in Figs. 207, 208 ; the ovaries are 
convoluted (Fig. 207), extending from Z, Fig. 
207, to the circular tube, where they have their 
greatest diameter ; the lips of the actinostome 
are carried in eight folds (Fig. 208), each one, /, 
corresponding to one of the radiating tubes, c, 
as in the ^Equoridse ; the lips project but little 
into the cavity of the bell. The tentacles are 
hollow, somewhat dumb-bell shaped at the base 

Fig. 206. The same, seen from the abactinal pole, in, month ; o, genital organs ; ?, tentacles. 

Fig. 207. Magnified view of two chymiferons tubes and genital glands. /, lips of actinostome. 

Fig. 208. Mode of carrying the lips of the actinostome. /, lips of actinostome ; c, chymiferons 
tube. 

Fig. 209. Magnified view of marginal tentacles. 




134 



MELICERTUM CAMPANULA. 



(Fig. 209), and taper rapidly ; they are thickly covered with lasso- 
cells. 

Artificial fecundation of these Medusse can be very readily made by 
keeping males and females for a day or two together in a glass jar, 
when we shall find, swimming near the bottom, innumerable spherical 
embryos (Fig. 210), in which the spheres of segmentation are still 



Fig. 211. 



Fig. 212. 



Fig. 213. 



Fig. 210 







Fig. 214. 



visible ; these elongate (Fig. 211), a cavity is formed at the blunt end, 
and w T e have a somewhat pear-shaped embryo, strongly ciliated, with 
walls of uniform thickness (Fig. 212), swimming about with great ve- 
locity ; these embryos attach themselves by the blunt end (Fig. 213), 
and soon elongate, as in the two middle figures of Fig. 213 ; the slen- 
der extremity next swells (Fig. 214), and this is the 
first trace of the sterile Hydra head. The wall of 
this swelling soon becomes somewhat indented, as 
in Fig. 214, where we have some of the successive 
stages of the sterile Hydra, until it forms a small 
horny bell, covering only the base of the long, ster- 
ile Hydra head, which terminates with ten stout, 
short tentacles, connected by a web. This Hydra- 
ritim differs considerably from that of Lafcea, but it 
still has sufficient resemblance to show their con- 
nection ; it is one of the easiest to raise, the 
Planula) are very hardy, and the development of 
the Hydrarium is readily followed. It grows in 
small tufts, which after six months had not attained a greater height 
than one third of an inch. 

Greenland (Fabricius) ; Massachusetts Bay (Agassiz). 
Cat. No. 351, Grand Manan, L. Agassiz. Medusa. 
Cat. No. 373, Nahant, 1863, A. Agassiz. Medusa. 
Cat, No. 448, Nahant, 1864, A. Agassiz. Medusa. 

Fig. 210. Spherical embryo. 

Fig. 211. The same, somewhat more advanced. 

Fig. 212. The same, immediately before becoming attached. 

Fig. 213. Group of embryos attached, in different stages of development. 

Fig. 214. Different stages of growth, beyond those of Fig. 213, till the sterile Hydra is fully 
developed. 




MELICERTUM GEORGICUM. 135 

Melicertum georgicum A. AGASS. 

Melicertum georgicum A. AGASS. ; in Agassiz's Cont. Nat. Hist. U. S., IV. p. 349. 1862. 

The Medusa (Fig. 215) is here figured to show the differences no- 
ticed between it and the New England representative of the genus. 
The pointed spherosome, the smaller number of the circular tentacles, 
the longer actinostome, and the termination of the genital organs, 
somewhat above the circular tube, are characters which readily distin- 
guish the M. georgicum from its Eastern representative. The knowl- 
edge of its complete development will settle this point definitely. The 
close resemblance of the mode of attachment of the ovaries to that 
of the ^Equorida?, referred to in the preceding species, is readily seen 

Fig. 215. Fig. 216. 





in Fig. 216. The genital folds are looped up on the upper side of the 
interior of the bell in an octagonal outline (Fig. 216), opening into the 
large cavity formed by the eight constrictions of the lips, /, of the acti- 
nostome. The difference is simply in the number of the chyniiferous 
tubes, as well as in the mode of carrying the lips of the actinostome. 
A simple flattening of the spherosome, and an increase in the number 
of chymiferous tubes, would give us an ^Equorea. This Medusa is 
found, in the summer, in the Gulf of Georgia, W. T. 

Fig. 215. Profile of Melicertum georgicum, natural size. 

Fig. 216. Digestive cavity and point of junction of the chymiferous tubes. I, lips of actinos- 
tome ; p, abactinal point of attachment of genital organs ; c, opening leading into chyniiferous 



tubes. Magnified. 



136 STAUROPHORA. 



STAUROPHORA BRANDT. 

Stauroplwra BRANDT (nan Forbes) ; in Mem. Acad. St. Petersburg, II. p. 399. 1835. 
Staurophora AGASS. ; in Mem. Am. Acad., IV. p. 300. 
Staurophora AGASS. Cont. Nat. Hist. U. S., IV. p. 351. 1862. 
Stauropliora LESS. Zooph. Acal., p. 297. 1843. 



Staurophora laciniata AGASS. 

Stauroplwra laciniata AGASS. ; in Mem. Am. Acad., IV. p. 300, PL 7. 1849. 
Staurophora laciniata AGASS. Cont. Nat. Hist. U. S., IV. p. 351. 1862. 
Staurophora laciniata A. AGASS.; in Proc. Boston Soc. Nat. Hist., IX. Figs. 1, 2, 3. 
Staurophora laciniata STIMPS. Mar. Inv. Grand Manan, p. 11. 1853. 

The youngest Medusa of Staurophora which has been observed 
(Fig. 215 a ) resembles to such an extent the young Melicertum (Figs. 
Fig, sis*. 203, 205), as readily to have been taken for dif- 
ferent stages of the same Jelly-fish, did not the 
absence of pigment eye-specks enable me to dis- 
tinguish them sufficiently easily. The develop- 
ment of the tentacles of the young Medusa ex- 
plains itself from the accompanying figures (Figs. 216 a , 217), as well 
as the changes of form of the digestive cavity, as it passes from a simple 
pendent pouch (Fig. 215 a ) through the different stages (a, &, c, Fig. 
218), where the digestive cavity loses little by little its individuality, 
the corners gradually extend along the chyiniferous tubes, and in 

Fig. 217. 

Fig. 2i6. SEBSSSSSSBSi Fig - - 1 ' 







quite young specimens (c, Fig. 218) the actinostome can no longer be 
distinguished among the innumerable small folds of the genital pouches. 
In Fig. 219 the young Staurophora has all the characters of the adult, 
excepting the size of the different parts. The violet pigment-spots at 
the base of the tentacles are quite apparent, being perceptible in 

Fig. 215*. Young Staurophora, with eight tentacles. 

Fig. 21 6". Quarter of the disk of a young Staurophora, with sixteen large tentacles. 
Fig. 217. Young Medusa, somewhat more advanced than Fig. 21 6*. 

Fig. 218. Different stages of the actinostome, intermediate between that of Figs. 215" and 219. 
o, the youngest ; b, the next ; c , the oldest. 




PTYCIIOGENA. 137 

younger stages. (Figs. 215 a , 216 a , 217.) Fi =- 219 - 

This Medusa grows to a large size, meas- 
uring often six to eight inches in diameter. 
It is one of the earliest Medusae to make 
its appearance, attains its full size rapidly 
from May to June, and by the end of 
June the dead Medusas are found in large 
numbers, floating about after storms ; by 
the middle of July they have all disap- 
peared. Found at Nahant. 

Massachusetts Bay (Agassiz) ; Maine (Stimpson). 

Cat. No. 275, Nahant, A. Agassiz. Young and old Medusae. 

Cat. No. 359, Boston Harbor, L. Agassiz. Medusa. 



Staurophora Mertensii BR. 

Staurophora Mertensii BR. ; in Mem. Acad. St. Petersb., IV. p. 400, Pis. 24, 25. 1838. 
Staurophora Mertensii LESS. Zooph. Acal., p. 297. 1843. 

Norfolk Sound (Mertens). 



PTYCHOGENA A. AGASS. 

The Medusa for which this genus has been established shows the 
intimate structural connection between Staurophora, Melicertum, and 
Polyorchis. The structure of the genital organs is an intermediate 
state of development between organs where the folds of the actinos- 
tome are lost in the genital folds, as in Staurophora, and the other 
extreme, where we have pendent genital organs attached to one ex- 
tremity of diverticulate chymiferous tubes, as in Polyorchis. 

Ptychogena lactea A. AGASS. 

The bell of this Medusa is rather high (Fig. 220), and the sphero- 
some of considerable thickness, giving this species an appearance of 
consistency, which is heightened by the striking contrast with the 
water of the milky genital organs and numerous marginal tentacles. 
The chymiferous tubes are broad ; at an equal distance on the abac- 
tinal and actinal ends, the edges of the tube become hacked ; the 
notches increase in size, and soon become long, sharp folds of the 
walls of the chymiferous tubes, projecting at right angles from the 
tubes (Fig. 221) ; the larger of these folds branch again. To these 
folds the genital organs are attached, forming as many connecting 

Fig. 219. Young Staurophora, having the general aspect of the adult. 

NO. II. 18 



138 



PTYCHOGENA LACTEA. 



pouches as there are points to the projections of the chymiferous 
tubes ; the folds become smaller and smaller (Fig. 222) towards the 
abactinal pole, and are connected by a loose fold with the actinostome. 
The opening of the actinostome is large ; its folds are small, and do 

Fig 221. 



Fig. 220. 





not form regular lips, but merely an irregular quadrangular frill. (Fig. 
223.) The tentacles are extremely numerous, opening into a large circu- 
lar tube ; they are very much flattened in one direction (/, Fig. 224) ; 
between every two tentacles is found a club-shaped appendage, made 



Fig 222. 





Fig. 224. 




up of large cells somewhat like those of Lafcea calcarata (&, Fig. 224) ; 
the tentacles are capable of great expansion, and when contracted are 
usually curled up tightly, as is the case in Melicertum and Staurophora ; 
they are very frequently tied up in festoons, as in Fig. 220. This 

Fig. 220. Profile view of Ptychogena, somewhat reduced. 

Fig. 221. Magnified view of the genital organs, seen from the abactinal pole. 

Fig. 222. The same as Fig. 221, seen in profile, on a somewhat smaller scale. 

Fig. 223. Actinostome. a, opening of actinostome ; p, point of attachment of the digestive 
cavity ; /, lips of the actinostome. 

Fig. 224. Magnified base of tentacles and club-shaped appendages. /, swelling of tentacles ; 
b, club-shaped appendages. 



PLUMULARIDJE. 139 

Medusa, like Tima, swims at a considerable depth below the surface. 
The action of the light and increase of temperature of the surface is 
sufficient to kill them in the course of half an hour ; the moment they 
are brought to the surface, the spherosome loses its transparency, the 
genital organs become dull, and the Medusa is soon completely decom- 
posed. This action is much more rapid than any thing of the kind 
which I have noticed even in Ctenophora3, Mertensia being the only 
genus in which the decomposing effects of light and heat are at all 
equal to what is produced here. This Jelly-fish must be a deep-water 
species, as they have only been found during a single fall, and then 
only for a few days, when they seemed quite abundant. 
Massachusetts Bay, Nahant (A. Agassiz). 



Family PLUMULARID^E3 Agass. 

Plumularidce AGASS. Cont. Nat. Hist. U. S., IV. p. 358. 1862. 
Sertularidce JOIIXST. (p. p.). Brit. Zooph., p. 89. 



AGLAOPHENIA LAMX. (restr. McCr.). 

Arjlaoplienia LAMX. (pars) ; in Bull. Soc. Phil. 1812. 
Aglaophenia McCu. Gymnoph. Charleston Harbor, p. 98. 1857. 
Af/laopJicnia AGASS. Cont. Nat, Hist. U. S., IV. p. 358. 1862. 
Plumularia LAMK. (pars). Aniru. s. Vert., II. p. 159. 



Aglaophenia pelasgica McCn. 

Aglaophenia pelasgica McCR. Gymn. of Charleston Harbor, p. 99. 1857. 
Serlularia pelasyica Bosc. Hist. Nat. Vers., HI. p. 122. 
Plumularia pelasgica LAMK. An. s. Vert., H. p. 167. 
Dynamena pelasgica BLAINV. Man. d'Actin., p. 484. 

Cat. No. 253, Florida, 1858, L. Agassiz. Hydrarium. 

Cat. No. 254, Tortugas, Fla, 1859, L. Agassiz. Hydrarium. 

Cat. No. 255, Hayti, 1858, Dr. D. F. Weinland. Hydrarium. 

Cat. No. 256, Gulf Weed, 1858, Dr. D. F. Weinland. Hydrarium. 

Cat. No. 257, Gulf Weed, 1858, Dr. D. F. Weinland. Hydrarium. 

Cat. No. 390, a hundred miles south of Cape Hatteras, A. S. Bick- 
more. Hydrarium. 

Cat. No. 391, a hundred miles south of Cape Hatteras, A. S. Bick- 
more. Hydrarium. 



140 PLUMULARIA. 



Aglaophenia triflda AGASS. 

Af/laophenia trifda AGASS. Cont. Nat. Hist. U. S., IV. p. 358. 1862. 
Aglaophenia cristata McCR. (non Lamk.). Gymn. Charl. Harb., p. 100. 

Charleston, S. C. (L. Agassiz). 

Cat. No. 252, Charleston, S. C., Jan. 1852, L. Agassiz. Hydrarium. 



Aglaophenia tricuspis McCR. 

AglaopJienia tricuspis McCR. Gymn. Charleston Harbor, p. 101. 

Charleston, S. C. (McCrady). 

Aglaophenia franciscana A. AGASS. 

Plumularia franciscana TRASK ; in Proc. Cal. Acad., March, 1857, p. 101, PI. 4, Fig. 3. 
Plumularia struthionides MURR. ; in Ann. & Mag. N. H., V. p. 251. 1860. 

San Francisco (A. Agassiz). 

Cat. No. 259, San Francisco, Cal., December, 1859, A. Agassiz. Hy- 
dromedusarium. 

Cat. No. 260, San Francisco, Cal., December, 1859, A. Agassiz. Hy- 
dromedusarium. 

PLUMULARIA LAMK. (restr. McCr.). 

Plumularia LAMK. (p. />.) An. s. Vert., II. p. 159. 
Plumularia McCR. Gymn. Charleston Harbor. 1857. 
Plumularia AGASS. Cont. Nat. Hist. U. S., IV. p. 358. 1862. 

Plumularia quadridens McCR. 

Plumularia quadridens McCR. Gymn. Charleston Harbor, p. 97. 
Plumularia quadridens AGASS. Cont. Nat, Hist. U. S., IV. p. 358. 1862. 

Charleston, S. C. (McCrady) ; Florida (L. Agassiz). 

Cat. No. 251, Ship Channel, Florida, January, 1856, L. Agassiz. 

Plumularia arborea DBS. 

Plumularia arborea DES. ; in Proc. Bost. Soc. Nat Hist., III. p. 65. 1848. 

Massachusetts Bay (Desor). 



SERTULARIAD.E. 

Family SERTULARIAD^E Johnst. 

Sertulariadce JOHXST. British Zoophytes, p. 57. 

DYNAMENA LAMX. (restr. Agass.). 

Di/namena LAMX.; in Bull. Soc. Phil. 1812. 

Dynamena AGASS. Cont. Nat. Hist. U. S., IV. p. 355. 1862. 

Dynamena pumila LAMX. 

Dynamena pumila LAMX. Cor. Flex., p. 179. 

Dynamena pumila JOHXST. Brit. Zooph., p. 66. 

Dynamena pumila AGASS. Cont. Nat. Hist. U. S., IV. pp. 326, 355, PI. 32. 1862. 

Dynamena pumila PACK. ; in Can. Nat. & Geol., Dec. 1863. 

Sertularia pumila MORCH ; in Beskriv. af Greenland, p. 97. 1857. 

Sertularia thuja FAB. (teste JMorch). Fauna Groenl., No. 456. 

This is one of the few of our Hydroids (Fig. 225) which have been 
compared in a living state with European specimens sent by Mr. Thos. 
J. Moore to the Museum, and brought across the Atlantic by Captain 
Anderson. Professor Agassiz, supposing it to be a distinct species, had 
previously given it the name of Dynamena Fabricii ; and before he 

Fig. 225. Fig. 226. 





had examined the development of the sessile Medusa (Fig. 226), sup- 
posed it to be the Hydroid of our Melicertum campanula. See, for the 
Hydroid of Melicertum, the description of that species. 

European and American shores of Atlantic Ocean (Ellis, Agassiz). 

Cat, No. 163, New Brighton, England, 1860, H. J. Clark. Hydrarium. 

Cat. No. 164, Liverpool, October, 1861, Thos. J. Moore. Hydromed. 

Cat. No. 165, Lynn, Mass., May, 1852, H. J. Clark. Hydromedusarium. 

Cat. No. 166, Nahant, July, 1862, A. Agassiz. Hydromedusarium. 

Cat, No. 167, Nahant, May, 1862, A. Agassiz. Hydromedusarium. 

Cat. No. 168, Nahant, July, 1861, A. Agassiz. Hydromedusarium. 

Fig. 225. Cluster of Dynamena pumila. 

Fig. 226. Magnified portion of stem of Fig. 225. 



142 DIPHASIA. 

Cat. No. 169, Nahant, June, 1855, H. J. Clark. Hydromedusarium. 

Cat. No. 170, Nahant, September, 1854, H. J. Clark. Hydrarium. 

Cat. No. 171, Chelsea Beach, L. Agassiz. Hydrarium. 

Cat. No. 172, Cohasset, Mass., L. Agassiz. Hydrarium. 

Cat. No. 173, Nantucket, Mass., August, 1857, L. Agassiz. Hydrome- 
dusarium. 

Cat. No. 174, Grand Manan, August, 1857, J. E. Mills. Hydromedu- 
sarium. 

Museum Diagram No. 18, after L. Agassiz. 



Dynamena corrdcina 

Dynamena cornicina McCu. Gymn. Charl. Harb., p. 102. 

Charleston, S. C. (L. Agassiz). 

Cat. No. 175, Charleston, S. C., L. Agassiz. Hydrarium. 

Cat. No. 176, Charleston, S. C., 1852, L. Agassiz. Hydrarium. 

DIPHASIA AOASS. 

Dipliasia AGASS. Cont. Nat. Hist. U. S., IV. p. 355. 1862. 

Diphasia fallax AGASS. 

Dipliasia fallax AGASS. Cont. Nat. Hist. U. S., IV. p. 355. 1862. 
Sertularia fallax JOIIXST. Brit. Zooph., p. 73, PI. 11, Figs. 2, 5, 6. 
Sertularia fallax STIMPS. Mar. luv. Grand Manan, p. 9. 1853. 

Grand Manan (W. Stimpson) ; Massachusetts Bay. 

Cat. No. 183, Eastport, Me., 1851, L. Agassiz. 

Cat. No. 184, Eastport, Me., 1852, W. Stimpson. 

Cat. No. 185, Massachusetts Bay, L. Agassiz. 

Cat, No. 427, Eastport, Me., 1861, Anticosti Expedition. 

Cat. No. 428, Eastport, Me., 1863, A. E. Verrill. 

Diphasia rosacea AGASS. 

Dipliasia rosacea AGASS. Gout. Nat. Hist. U. S., IV. p. 355. 1862. 

Sertularia rosacea Lixx. Sy-st. 1306. 

Sertularia rosacea JOHXST. Brit. Zooph., p. 64. 

Sertularia rosacea PACK.; in Can. Nat. & Geol., Dec. 1863. 

? Sertularia plwnea DES. ; in Proc. Bost. Soo. N. H., HI. p. G6. 1848. 

Nahant, Suisconset, Mass. (A. and L. Agassiz). 

Cat. No. 180, New Brighton, England, Oct. 1860, H. J. Clark. Hy- 
dromedusarium. 

Cat. No. 181, Nahant, Mass., July, 1861, A. Agassiz. Hydromedusarium. 

Cat, No. 182, Suisconset, Mass., July, 1849, L. Agassiz. Hydromedu- 
sarium. 



SERTULARIA. 143 

Diphasia corniculata A. AGASS. 

Sertularia corniculata MURRAY ; in Ann. & Mag. N. II., X. PI. XI. Fig. 3. 1860. 

Bay of San Francisco (Murray). 

SERTULARIA LINN, (emend. Agass.). 

Sertularia Lixx. Syst. Nat. 

Sertularia AGASS. Cont. Nat. Hist. U. S., IV. p. 356. 1862. 

Sertularia abietina LINN. 

Sertularia abietina Lixx. Syst. 1307. 

Sertularia abietina FAB. Fauna Groenlandica. No. 453. 

Sertularia alnetlna JOHXST. Brit. Zooph., p. 7.5. 

Sertularia abietina AGASS. Cont. Nat. Hist. U. S., IV. p. 356. 1862. 

St. George's Bank, Newfoundland ; Mingan Islands. 

Cat. No. 195, New Brighton, Eng., Oct. 1860, H. J. Clark. Hydrarium. 

Cat. No. 196, Liverpool, Eng., 1861, Thos. J. Moore. 

Cat. No. 197, St. George's Bank, W. Stimpson. 

Cat. No. 419, Mingan Islands, 1861, Anticosti Expedition. 

Sertularia cupressina LINN. 

Sertularia cupressina Lixx. Syst. 1308. 

Sertularia cujirrssnia JOHXST. Brit. Zooph., p. 80. 

Sertularia cupressina LEIDY. Inv. R. I. and N. J., p. 6. 

Sertularia cupressina AGASS. Cont. Nat. Hist. U. S., IV. p. 356. 1862. 

Absecom Beach (Leidy) ; Massachusetts Bay (Agassiz). 
Cat. No. 202, New Brighton, Eng., October, 1860, H. J. Clark. Hy- 
clromedusarium. 

Cat, No. 203, Beverly, July, 1861, A. Agassiz. Hydrornedusariiim. 
Cat. No. 204, Nahant, May, 1862, A. Agassiz. Hydromedusarium. 
Cat. No. 205, Chelsea, May, 1862, H. J. Clark. Hydromedusarium. 
Cat. No. 206, Eastport, Me., 1851, W. Stimpson. Hydromedusarium. 
Cat. No. 207, Mount Desert, Me., W. Stimpson. Hydromedusarium. 
Cat. No. 208, Suisconset, July, 1849, L. Agassiz. Hydromedusarium. 
Cat, No. 209, Suisconset, Mass., L. Agassiz. Hydrarium. 
Cat. No. 211, Lynn, Mass., Jan. 1861, H. J. Clark. Hydrarium. 
Cat, No. 212, Massachusetts Bay, L. Agassiz. 



144 SERTULARIA ANGUINA. 



Sertularia argentea ELL. & SOL. 

Sertularia argentea ELLIS & SOL. Zooph., p. 38. 

Sertularia argentea JOHNST. Brit. Zooph., p. 79, PI. 15, Fig. 3 ; PI. 14, Fig. 3. 

Sertularia argentea AGASS. Cont. Nat. Hist. U. S., IV. p. 356. 1862. 

Sertularia argentea STIMPS. Mar. Inv. Grand Manan, p. 8. 1853. 

Sertularia argentea MORCH.; in Bosk, af Gronland, p. 97. 

Sertularia fastigiata FAB. (teste Morch). Fauna Groulandica, No. 458. 

Grand Manan (W. Stimpson). 

Cat. No. 213, New Brighton, Oct. I860, H. J. Clark. Hydrarium. 



Sertularia falcata LIXN. 

Sertularia falcata LINN. Syst. 1309. 

Sertularia falcata AGASS. Cont. Nat. Hist. U. S., IV. p. 356. 1862. 
Plumularia falcata JOHNST. Brit. Zooph., p. 90, PL 21, Figs. 1, 2. 
Plumularia falcata PACK.; in Can. Nat. & Zool. Dec. 1863. 
Plumularia falcata STIMPS. Mar. Inv. Grand Manan, p. 8. 1853. 
Sertularia tenerissima STIMPS. Mar. Inv. Grand Manan, p. 8. 1853. 

Grand Manan (W. Stimpson) ; Eastport, Me. (W. Stimpson) ; Mingan 
Islands ; Massachusetts Bay (Agassiz). 

Cat, No. 218, New Brighton, Eng., 1860, H. J. Clark. Hydrarium. 

Cat. No. 219, Grand Manan. 

Cat. No. 220, Eastport, Me., 1853, W. Stimpson. Hydromedusarium. 

Cat. No. 221, Grand Manan, W. Stimpson. 

Cat. No. 222, Eastport, Me., 1851. Hydrarium. 

Cat. No. 223, Suisconset, Mass., L. Agassiz. Hydrarium. 

Cat. No. 224 (P. tenerissima), Grand Manan, W. Stimpson. Hydro- 
medusarium. 

Cat. No. 415, Mingan Islands, 1861, Anticosti Expedition. Hydrarium. 

Cat, No. 416, Eastport, Me., 1861, A. E. Verrill. Hydrarium. 

Cat. No. 417, Mingan Islands, 1861, Anticosti Expedition. Hydrarium. 

Cat. No. 424, Eastport, Me., 1861, Anticosti Expedition. 



Sertularia anguina TRASK. 

Sertularia anguina TRASK ; in Proc. Cal. Acad. N. S., p. 100, PI. 5, Fig. 1. 1857. 
Sertularia laurata MURRAY ; in Ann. & Mag. N. H., V. p. 250, PI. XI. Fig. 2. 1860. 

Bay of San Francisco (Trask, Murray); Monterey, Punta de los 
Reyes, Tomales Point (Trask). 



SERTULARIA TURGIDA. 145 

Sertularia gracilis A. AGASS. 

Plumularia gracilis MURRAY ; in Ann. & Mag. N. H., V. p. 251, PI. XTT. Fig. 1. 1860. 

Bay of San Francisco (Murray). 

Sertularia myriophyllum LINN. 

Sertularia myriophyllum LINX. Syst. 1309. 
Plumularia myriophyllum JOHNST. Brit. Zooph., p. 99. 

Cat. No. 214, Massachusetts Bay, L. Agassiz. 
Cat. No. 418, Mingan Islands, Anticosti Expedition. 
Cat. No. 429, Eastport, Me., A. E. Verrill. 
Cat. No. 430, Eastport, Me., A. E. Verrill. 

Sertularia latiuscula STIMPS. 

Sertularia latiuscula STIMPS. Mar. Inv. Grand Manan, p. 8. 1853. 

Grand Manan (W, Stimpson). 

Sertularia filicula ELL. & SOL. 

Sertularia fiUcula ELLIS & SOL. Zooph., p. 57, PI. 6, Figs, c, C. 
Sertularia flicula STIMPS. Mar. Inv. Grand Manan, p. 8. 1853. 
Sertularia Jilicula JOHNST. Brit. Zooph., p. 76, PI. 14, Fig. 1. 

Grand Manan (W. Stimpson). 

Sertularia furcata TRASK. 

Sertularia furcata TRASK ; in Proc. Cal. Acad., March, 1857, p. 101, PI. V. Fig. 2. 

San Francisco (Trask). 

Sertularia turgida TRASK. 

Sertularia turgida TRASK ; in Proc. Cal. Acad., March, 1857, p. 101, PI. IV. Fig. 1. 

San Francisco (Trask). 



Sertularia producta 

Sertularia producta STIMPS. Mar. Inv. Grand Manan, p. 8. 1853. 

Grand Manan (W. Stimpson). 
xo. ii. 19 



146 COTULINA. 

AMPHITROCHA AGASS. 

Ampliitrocha AGASS. Cont. Nat. Hist. U. S., IV. p. 356. 1862. 

Amphitrocha rugosa AGASS. 

Ampliitrocha rugosa AGASS. Cont. Nat. Hist. U. S., IV. p. 356. 1862. 

Sertularia rugosa LINN. Syst. 1308. 

Sertularia rugosa FAB. Fauna Gronlandica. No. 454. 

Sertularia rugosa JOHNST. Brit. Zooph., p. 63, PI. X. Figs. 4-6. 

Sertularia rugosa STIMPS. Mar. Inv. Grand Manan, p. 9. 1853. 

Sertularia rugosa MoRCH ; in Besk. af Grb'nland, p. 97. 

Amphitrocha cincta AGASS. Cont. Nat. Hist. U. S., IV. p. 356. 1862. 

Massachusetts Bay (L. Agassiz) ; Grand Manan (W. Stimpson). 
Cat. No. 226, Nahant, April, 1855, H. J. Clark. Hydromedusarium. 
Cat. No. 227, Nahant, May, 1855, H. J. Clark. Hydromedusarium. 
Cat. No. 228, Nahant, August, 1854, H. J. Clark. Hydrarium. 
Cat. No. 229, Nahant, July, 1861, A. Agassiz. Hydrarium. 
Cat. No. 230, Nahant, September, 1854, H. J. Clark. Hydrarium. 
Cat. No. 406, Nahant, July, 1862, A. Agassiz. 

COTULINA AGASS. 

Cotulina AGASS. Cont. Nat. Hist. U. S., IV. p. 356. 1862. 

Cotulina tricuspidata A. AGASS. 

Sertularia tricuspidata ALDER (non Murray). Cat. Zooph. Nor thumb, and Durham, p. 21, PI. H. 

Figs. 1, 2. 1857. 
Sertularia tricuspidata PACK.; in Can. Nat. & Geol. Dec. 1863. 

Massachusetts Bay (L. Agassiz). 

Cat. No. 233, Massachusetts Bay, L. Agassiz. 

Cat. No. 234, Massachusetts Bay, L. Agassiz. 

Cat, No. 235, Eastport, Me., July, 1851, W. Stimpson. 

Cat. No. 236, Eastport, Me., July, 1852, W. Stimpson. 

Cotulina polyzonias AGASS. 

Cotulina polyzonias AGASS. Cont. Nat. Hist. U. S., IV. p. 356. 1862. 
Sertularia polyzonias LINN. Syst. 813. 

Sertularia polyzonias JOHNST. Brit. Zooph., p. 61, PI. X. Figs. 1-3. 
Sertularia polyzonias MORCH ; in Besk. af Gronland, p 97. 1857. 
Sertularia polyzonias STIMPS. Mar. Inv. Grand Manan, p. 9. 1853. 
Sertularia polyzonias PACK.; in Can. Nat. & Geol. Dec. 18C3. 
Sertularia pinnata GOULD. Rep. Inv. Mass., p. 350. 

Eastport, Me. (A. E. Verrill) ; Mingan Islands (Anticosti Expedition); 
Grand Manan (W. Stimpson). 



HALECIUM. 147 

Cat, No. 426, Eastport, Me., 1863, A. E. Verrill. 

Cat. No. 434, Mingan Islands, 1861, Anticosti Expedition. 



Cotulina tamarisca A. AGASS. 

Scrtularia tamarisca LINN. Syst. 1307. 

Sertularia tamarisca JOHNST. Brit. Zooph., p. 74, PI. XIII. Figs. 2-4. 

Eastport, Me. (A. E. Verrill ; Sea-Coal Bay, N. S. (Anticosti Expedi- 
tion) ; Massachusetts Bay (Agassiz). 

Cat. No. 231, Grand Manan, W. Stimpson. Hydrarium. 
Cat. No. 232, Massachusetts Bay, W. Stimpson. Hydrarium. 
Cat. No. 425, Eastport, Me., 1863, A. E. Verrill. 
Cat. No. 431, Sea-Coal Bay, N. S., 1861, Anticosti Expedition. 



Cotulina Greenei A. AGASS. 



Sertularia tricuspidata MURRAY (orc Alder). Ann. & Mag., V. p. 200. 1860. 
Sertularia Greenei MURRAY. Ann. & Mag., V. p. 504. 1860. 

Growing in very thick clusters, resembling somewhat in their ap- 
pearance fine brushes of Dynamena pumila. It is supported by a very 
slender stem, which branches near the base ; the branches rise verti- 
cally, forming fan-shaped tufts, in which all the stems reach one level ; 
there is no prominent main stem. It attains a height of from two to 
three inches. The secondary branches arise in a similar way, near the 
base of the primary branches. The sterile hydne have two prominent 
exterior points to support the operculum, and two smaller ones near 
the stem. The reproductive calycles are conical and slightly corru- 
gated, attached by the apex, and terminate in a bottle-shaped neck. 

San Francisco, Cal. 

Cat. No. 436, San Francisco, Cal., Normal School, Salem. 



HALECIUM OKEN. 

Halecium OKEN. Lehrb. der Naturg. 1815. 

Thoa LAMX. Pol. Cor. Flex. 1816. 

Halecium AGASS. Cont. Nat. Hist. U. S., IV. p. 357. 1862. 



Halecium muricatum JOHNST. 

Haled am muricatum Jonxsx. Brit. Zooph., p. 40, PI. IX. Figs. 3, 4. 
Sertularia muricata ELLIS & SOL. Zooph., p. 59, PL VII. Figs. 3, 4. 

Cat, No. 421, Eastport, Me., 1863, A. E. Verrill. 



148 THUIARIA. 



Halecium halecinum JOHNST. 

Halecium halecinum JOIIXST. Brit. Zooph., p. 38, PI. VIII. 

Halecium halecinum AGASS. Cont. Nat. Hist. U. S., IV. p. 357. 1863. 

Halecium halecinum MORCH ; in Beskriv. af Grdnland, p. 97. 1857. 

Sertularia halecina LINN. Syst. 1308. 

Sertularia halecina FAB. Fauna Gronlandica. No. 455. 

Eastport, Maine ; Massachusetts Bay. 

Cat. No. 243, New Brighton, England, Oct. 1860, H. J. Clark. 

Cat. No. 244, Suisconset, Mass., L. Agassiz. 

? Cat. No. 245, Nahant, Mass., Sept. 1854, H. J. Clark. 



GRAMMARIA STIMPS. 

Grammaria STIMPS. Mar. Inv. Grand Manan, p. 9. 1853. 
Grammaria AGASS. Cont. Nat. Hist. U. S., IV. p. 357. 1862. 



Grammaria gracilis STIMPS. 

Grammaria gracilis STIMPS. Mar. Inv. Grand Manan, p. 9. 1853. 

Grand Manan (W. Stimpson). 

Grammaria robusta STIMPS. 

Grammaria robusta STIMPS. Mar. Inv. Grand Manan, p. 9, Fig. 3. 1853. 

Grand Manan (W. Stiinpson). 

THUIARIA FLEM. 

Thuiaria FLEM. British Animals. 1828. 

Thuiaria thuja FLEM. 

Thuiaria thuja FLEM. British Animals, p. 545. 1828. 
Sertularia thuja LINN. Syst. 1308. 
Thuiaria thuja JOHNST. Brit. Zooph., p. 83. 

Mingan Islands, N. S. 
Cat. No. 240, Norway, M. Sars. 

Cat. No. 420, Mingan Islands, N. S., Anticosti Expedition, 1861. Hy- 
drarium. 



TUBULAROE. 149 



SUBORDER TUBULARI^E AGASS. 

Tubularity AGASS. Cont. Nat. Hist. U. S., IV. p. 338. 1862. 
Tubularlnn EHHENB. Corall. d. Rothen Meeres. 
Tubularina and Ilydrina JOHXST. Brit. Zooph., p. 29. 



Family NEMOPSID^E Agass. 

Nemopsidce AGASS. Cont. Nat. Hist. U. S., IV. p. 345. 1862. 

NEMOPSIS AGASS. 

Nemopsis AGASS. ; in Mem. Am. Acad., IV. p. 289. 1849. 

Nemopsis McCR. Gymn. Charl. Harbor, p. 57. 

Nemopsis AGASS. Cont. Nat. Hist. U. S., IV. p. 345. 1862. 

< *"''-- 

Nemopsis Bachei AGASS. 

Nemopsis Bachei AGASS. ; in Mem. Am. Acad., IV. p. 289, Fig. 1849. 
' Nemopsis''Bachei' AGASS. Cont. Nat. Hist. U. S., IV. p. 345. 1862. 
Nemopsis Gibbesi McCR. Gymn. Charl. Harb., p. 58, PL 10, Figs. 1-7. 
Nemopsis Bachei A. AGASS. ; in Proc. Bost. Soc. Nat. Hist., IX. p. 98, Figs. 26, 27. 

Owing to the great changes through which Nemopsis passes before 
it reaches its adult form (compare Figs. 227-230), it is impossible 
to decide at present, before having seen the Nemopsis Gibbesi of 
McCrady, found at Charleston, whether he has not described again, 
under a new name, the N. Bachei found by Professor Agassiz in Vine- 
yard Sound in 1848, and of which a wood-cut was published in the 
Memoirs of the American Academy for 1849. The circumstances under 
which the drawing was made precluded the possibility of great accu- 
racy ; it was a simple sketch ; and as this Medusa has not been ob- 
served since, until the publication of McCrady's paper on the Medusas 
of Charleston Harbor, it is not astonishing that he should have described 
it as a new species, having only for his guide that single wood-cut. 

I have had, during the summer of 1861, the opportunity Fig. 227. 
of observing this Medusa, at the time when it had only 
four tentacles to each marginal bulb (Fig. 227), no ova- 
ries, and was not more than a sixteenth of an inch in diam- 
eter. The shape of the bell, and of the oral tentacles, the 
mode of branching of the digestive cavity and of the tentacles, agree 
so well with the drawings and descriptions of McCrady of similar stages 
in N. Gibbesi., that I am inclined to consider them as identical. The 

Fig. 227. Youngest Nemopsis observed, having four tentacles at the base of each chymiferous 
tube. 




150 



NEMOPSIS BACHEI. 



Fig. 223. 




only point which would throw some doubt upon this identification, is 
the time of the year at which it appears in Charleston and in Vineyard 

Sound ; in the former place it is a Avinter species, 
found in December, while at Naushon it Avas very 
common in September. The marginal tentacles in- 
crease in the same way as in Bougainvillia ; those 
which are nearest the middle of the bulb, at its apex, 
are developed first, and ne\v tentacles are constantly 
growing near the base of the conical-shaped bulb. 
(Figs. 228, 229.) They are at first slender-pointed 
tentacles, but soon become rounded at the extremi- 
ties, with sensitive eye-specks at the base, and change 
into contractile tentacles, having a slight swelling at 
the extremity ; this SAvelling, ho\vever, depends very much upon the 
state of contraction of the tentacles. The Fig . 229 . 

adult frequently SAvim about Avith the 
marginal tentacles contracted to mere 
knobs, rising from the sensitive bulb (Fig. 
229); during their movements, which are 
rapid and powerful, the oral tentacles 
(Fig. 230) are thrown up and doAA'n at 
each pulsation with great violence, and 
seem to be important appendages in di- 
recting the motions of the animal. With 
the exception that the tentacles, AA T hich are carried erect upon their 
Fig 230 base, are not contractile like the others, and 

have a more clavate appearance (Figs. 227- 
230), they differ in no AA 7 ay from the others. 
There are eye-specks at the base of the erect 
tentacles, as Avell as at the base of the con- 
tractile ones, and the supposition that in 
this genus the eyes Avere supported upon a 
peduncle, like the eyes of a lobster, was 
founded upon the dark club terminating this 
pair of tentacles ; this color is due entirely 
to a thickening of the extremity by contrac- 
tion. Male specimens have been found meas- 
uring more than half an inch in diameter. 
The proboscis projects Avell beyond the line of the genital organs (Fig. 
231) ; at first, in young stages, the genital organs occupy but a very 

Fig. 228. Nemopsis somewhat more advanced than Fig. 227, having the second and third set 
of tentacles developed. 

Fig. 229. Magnified view of the sensitive bulb at the base of one of the chymiferous tubes, c. 

Fig. 230. Nemopsis in which the genital organs extend a considerable distance along the chy- 
miferous tubes. 





ACAULIS. 151 

small portion of the upper part of the chymiferous tubes (Figs. 227, 
228), but with advancing age extend farther down (Figs. 230, 231), and 
in the adult they reach the circular tube. The genital organs remind 
us, in their mode of growth, of what we find in Melicertum and Stau- 
rophora. The outline of the bell is but little changed from the earliest 
stages to the more advanced ; it simply grows Fig . 2 3i. 

somewhat more globular. The sensitive bulb 
as well as the ovaries are slightly yellowish. 

McCrady describes the Hydroid of this 
Medusa as a free floating community ; I 
greatly incline to the opinion of Professor 
Allman, that we have in these free Hydroids 
nothing but the detached head of some Tubu- 
larian ; certainly the figures given by Mc- 
Crady of the Hydroid of Nemopsis, and by 
Stimpson of Acaulis, remind us very forcibly 
of detached heads of Tubularians. The heads 
of our Pennaria (Globiceps tiarella Ayres) 
frequently drop off, and nothing is more common than to see, at the 
time of breeding, several of these heads, covered with Medusae, floating 
about in the jars where the Pennarige are kept, and to have the Me- 
dusae buds come to maturity while the head is thus detached, and 
would readily be mistaken for something like a free Hydroid. During 
four successive summers I have hunted in vain in the hope of finding 
one of these free Hydroids among the innumerable small Medusae 
which must have just separated from the Hydrarium, which makes it 
probable that the Hydrarium is fixed, and not floating. 

Vineyard Sound (L. Agassiz) ; Buzzard's Bay (A. Agassiz) ; Charles- 
ton Harbor (McCrady). 

Cat. No. 44, Nantucket, Mass., June, 1849, L. Agassiz. Medusa. 

Cat. No. 272, Naushon, Mass., Sept. 1861, A. Agassiz. Medusa. 



ACAULIS STIMPS. 

Acaulis STIMPS. Mar. Inv. Grand Manan, p. 10. 1853. 
Acaulis AGASS. Cont. Nat. Hist. U. S., IV. p. 345. 1862. 




Acaulis primarius 

Acaulis primarius STIMPS. Mar. Inv. Grand Manan, p. 10, PI. 1, Fig. 1. 
Acaulis primarius AGASS. Cont. Nat. Hist. U. S., IV. p. 345. 18G2. 

Grand Manan (W. Stimpson). 

Cat. No. 162, Grand Manan, W. Stimpson. Hydromedusarium. 

Fig. 231. Magnified view of the genital organs, the actinostome, and the oral tentacles. 



152 BOUGAINVILLE^. 



Family BOUGAINVILLE^E Liitk. 

Bougainvillece LUTK. ; in Vidensk. Med., p. 29. 1849-50. 
BougainvilUdce GEGENB. ; in Zeit. f. Wiss. Zool., p. 220. 1856. 
Hippocrenidce McCii. Gyran. Charl. Harbor, p. 56. 
Bougainvilluhe AGASS. Cont. Nat. Hist. U. S., IV. p. 344. 1862. 
Eudendroidce AGASS. Cont. Nat. Hist. U. S., IV. pp. 282, 342. 1862. 



BOUGAINVILLIA LESS. 

Boiigainvittia LESS.; in Ann. ties Sc. Nat., V. 1836. 

Hippocrene MERT. ; (Preocc. Moll.) in Mem. Acad. St. Petersburg, p. 229. 1835. 

Hippocrene AGASS. ; in Meui. Ani. Acad., p. 250. 1849. 



Bougainvillia Mertensii AGASS. 

Bougainvillia Mertensii AGASS. Cont. Nat. Hist. U. S., IV. p. 344. 1862. 

Hippocrene Bougainvillei BR. (non Less.) ; in Mem. Acad. St. Petersburg, p. 293, PI. 20. 1838. 

If the Hydrarium, collected at San Francisco, is the Hydrarmm of 
Bougainvillia Mertensii, there can be no doubt of the specific differ- 
ence between it and Bougainvillia super cUiaris Agass. It grows quite 
luxuriously, attaining a height of nearly two and a half inches ; the 
stems are very stout, particularly the main branch, which near the 
base is exceedingly robust ; the branches are at least three times as 
stout as those of the Hyclrarium of our Bougainvillia, which is slen- 
der, and always branches quite loosely. In the California species the 
brandies succeed each other rapidly, and are crowded on the sides of 
the main stem. This would seem to prove that this species, like the 
Coryne rosaria, is the representative on the Pacific coast of its eastern 
congener, and that neither the Coryne mirdbilis nor the Bouyain- 
villia superciliaris are circumpolar species, like the Toxopneustes dro- 
bachiensis. 

This species is undoubtedly the Hippocrene Bouyainmllei Br. which 
Mertens found at Mathaei Island, in Behring's Strait, and which is 
figured in the Memoirs of the Academy of St. Petersburg for 1838, 
Vol. II. The ramifications of the tentacles surrounding the actinos- 
tome are very numerous, and the eye-specks at the base of the mar- 
ginal tentacles small. The spherosome has a slight bluish tinge ; the 
chymiferous tubes, the tentacles surrounding the mouth, and the mar- 
ginal tentacles, are straw r -colored ; the base of the tentacles is yellow- 
ish-brown. This species is much larger than either Boiiyainvillia su- 
2)erciliaris or B. madoinana ; it was quite common during the summer, 
in the harbor of Port Townsend, at the northwest boundary, in the 



BOUGAINVILLIA SUPERCILIARIS. 153 

Gulf of Georgia, and was also found in the harbor of San Francisco 
during May and November. 

Behring's Strait (Brandt) ; Gulf of Georgia, W. T. (A. Agassiz). 

Cat. No. 33, San Francisco, Cal., March, 1859, A. Agassiz. Hydrarium. 

Cat. No. 49, Gulf of Georgia, W. T., May, 1859, A. Agassiz. Medusa. 



Bougainvillia superciliaris AGASS. 

Bougainvillia superciliaris AGASS. Cont. Nat. Hist. U. S., IV. pp. 289, 291, Figs. 37 -39 ; p. 344, 

PI. 27, Figs. 1-7. 1862. 

Hippocrene superciliaris AGASS. ; in Mem. Am. Acad., IV. p. 250, Pis. 1-3. 
Hi/ipocrejie superciliaris STIMPS. Mar. Inv. Grand Manan, p. 11. 1853. 
Bouyaindllia superciliaris A. AGASS. ; in Proc. Bost. Soc. Nat. Hist., IX. Figs. 24, 25. 
Hippocrene Bougainvillei GOULD (nee Br., nee Less.). Rep. Inv. Mass., p. 348. 1841. 
? Tubularia ramosa GOULD. Rep. Inv. Mass., p. 350. 1841. 
? Eudendrium cingulatum STIMPS. Mar. Inv. Grand Manan, p. 9. 1853. 

The development of the young Medusae of the species, formerly re- 
ferred to Bougainvillia, shows beyond doubt that the genera Bougain- 
villia and Margelis are founded upon structural differences ; from the 
earliest stages we can trace the peculiar short and long digestive cavities 
so characteristic of these two genera, as well as the differences in the 
form of the bell. BougainmUia superciliaris (Fig. 232), of which a 

Fig. 232. 




complete description has already been given by Professor Agassiz, in 
the Memoirs of the American Academy for 1849, is one of our most 
common Medusae, but readily escapes notice on account of its small size. 
The Hydrarium (Fig. 233) has also been figured by Professor Agassiz in 
Vol. IV. of his Contributions, but the development has not been traced 
before. The Medusa buds are found along the stem below the heads ; 
Figs. 234, 235 are early stages, when the bell is elongated, and inca- 

Fig. 232. Magnified profile view of adult Bougainvillia superciliaris. 
NO. n. 20 



154 



BOUGAINVILLIA SUPERCILIARIS. 



pable of expansion and contraction. In Figs. 236, 237, which are some- 
what older Medusas in different attitudes, the digestive cavity is well 



Fig. 233. 



Fig. 235. 




Fig. 234. 





Fig. 236. 




developed, and from the four corners of the actinostome bulge out four 
club-shaped appendages, the first traces of the oral tentacles. There 



Fig. 238. 



Fig. 237. 





are two well-developed tentacles, which were at first a mere knob, with 
distinct eye-specks. (Fig. 234.) The bell is quite thin at this stage, and 

Fig. 233. Ilydromedusarium of Bougainvillia superciliaris. 

Fig. 234. Young elongated Medusa. 

Fig. 235. Somewhat more advanced than Fig. 234. 

Fig. 236. Appearance a short time before separating from the stem, in a contracted state. 

Fig. 237. The same as Fig. 236, expanded. 

Fig. 238. Young Bougainvillia, immediately after its liberation from the Ilydromedusarium. 





MARGELIS. 155 

of uniform thickness, the veil large and powerful ; Fig. 239. 

the abactinal portion of the bell becomes somewhat 
more thickened, and when it has separated from 
the Hydrarium (Fig. 238), the tentacles far exceed 
in length the diameter of the bell, the sensitive 
bulb (Fig. 239) having become quite well defined 
in outline ; it is somewhat quadrangular, filled with 
dark pigment cells, p, and at the base of each tentacle a bright eye- 
speck, e, is formed ; the club-shaped oral appendages soon Fig 
begin to branch, additional tentacles appear in pairs on each 
side of the original pair (Fig. 240), and the young Medusa 
soon assumes all the principal features of the adult, as in Fig. 
232, with the exception of the simpler character of the ten- 
tacles of the actinostome. 

Massachusetts Bay (Agassiz). 

Cat. No. 27, Nahant, Mass., Sept. 1854, H. J. Clark. Hydrarium. 

Cat. No. 28, Beverly, July, 1861, A. Agassiz. Hydromedusarium. 

Cat. No. 29, Nahant, July, 1861, A. Agassiz. Hydrarium. 

Cat. No. 30, Newport, R I., Prof. J. Leidy. Hydromedusarium. 

Cat. No. 31, Newport, R L, S. Powell. Hydromedusarium. 

Cat. No. 408, Nahant, July, 1862, A. Agassiz. Hydromedusarium. 

Cat. No. 447, Nahant, July, 1864, A. Agassiz. Hydromedusarium. 

Museum Diagrams, Nos. 20, 22, after A. Agassiz. 



MARGELIS STEENST. 

Margelis STEENST.; in Vidensk. Meclel. for 1849-50, p. 43. 
Margelis AGASS. Cont. Nat. Hist, U. S., IV. p. 344. 18C2. 
Bougainvillia LESS.; in Ann. Sc. Nat., V. 1836. 
Hippocrene McCn. (nee Mert. nee Agass.). Gymn. Charl. ILirb., p. 61. 

The structural differences observed in the European Bougainvillia 
britannica Forbes, and the Hippocrene, carolinensis McCrady, seem 
sufficient to separate them from the genus Hippocrene, as has been 
proposed by McCrady. The digestive cavity, instead of being a short, 
rounded sac, attached at some distance below the highest point of 
the chymiferous tubes, is long and slender, swelling slightly towards 
its actinal end, and attached at the point of junction of the chymif- 
erous tubes ; the peduncle of the actinostome is long, the oral tenta- 
cles branch only two or three times ; these are more than specific 
differences ; they are structural differences, unlike the differences we 
find between species of the genus Bougainvillia, as between the 

Fig. 239. Magnified view of sensitive bulb. />, pigment-cells ; e, eye-speek. 
Fig. 240. Tentacular bulb with the young tentacles, c, chymiferous tube ; 1, 2, 3, 4, different 
sets of tentacles. 



156 



MARGELIS CAROLINENSIS. 



Hippocrene- supertittaris of the northeast coast, and the Hippocrene 
Mertensii of the northwest coast, which are differences in the propor- 
tion of the digestive cavity, its position, the thickness of the bell, and 
the mode of branching of the oral tentacles. 



Margelis carolinensis AGASS. 

Margelis carolinensis AGASS. Cont. Nat. Hist. U. S., IV. p. 344. 1862. 
Hippocrene carolinensis McCR. Gymn. Charl. Harbor, p. 62, PI. 10, Figs. 8-10. 

Adult females, taken at Naushon in September, measured about one 
third of an inch (Fig. 241) ; the main stein of the four oral tentacles 



Fig. 241. 





Fig. 242. 



branches twice, and each of these branches twice (Fig. 242) ; the cav- 
ity of the bell is small and globular ; the marginal bulbs are large and 

conical, and give rise (Fig. 243) to ten or 
twelve tentacles, which are long, slender, and 
not usually carried curled up tightly near the 
bulb ; the bulb is colored with brilliant red 
pigment-cells, surrounded by a green edge, 
bordered with bright yellow, and in the yel- 
low border are placed the black eye-spots, 
giving to the base of the tentacles a very 
striking appearance ; the digestive cavity is 
brick red, and when the folds of the genital 
glands are expanded by eggs, they hang down in four pouches, so as to 
hide the peduncle of the digestive cavity. (Fig. 242.) The outline of 

Fig. 241. Adult Margelis, seen in profile ; magnified. 

Fig. 242. Digestive cavity, genital pouches, oral tentacles, and actinostome. 

Fig. 243. Sensitive bulb at base of one of the chymiferous tubes. 




MARGELIS CAROLINENSIS. 157 

the bell is almost spherical ; the thickness of the disk is so great that 
the cavity of the bell only extends to half the height of the vertical 
axis. (See Fig. 241.) 

In young specimens (one tenth of an inch in height) just liberated 
from the Hydromedusarium, the outline of the disk is bell-shaped (Fig. 
244), the cavity of the bell is large in proportion, and the thickness of 
the upper part of the bell is not one third of the height of the actinal 
axis. The digestive cavity and the peduncle are one ; it is bottle- 
shaped, cylindrical, and not yet divided by four longitudinal furrows 
into genital pouches. These small Medusae have, like the young of 
Bougainvillia, when freed from the Hydromedusarium, but two tenta- 
cles at the base of each of the chymiferous tubes (Figs. 244, 245), the 



Fig. 244. 





digestive cavity terminates likewise with perfectly simple, stiff oral ten- 
tacles, which begin to branch only in somewhat more advanced stages. 
The generic identity of Bougainmllia britannica with our Margelis 
carolinensis is perhaps not better shown than by the agreement of the 
young Medusae in all their essential features, while the Hydrarium shows 
that the specific difference between the English and American represen- 
tatives is not to be questioned. See the observations of Dalyell on the 
development of his Tubularia ramosa, PL XL Vol. I., Animals of Scot- 
land, and the figures of Hodge of Podocoryne Alder i, which I presume 
is only a young of one of the species of Bougainvillia (Margelis Steenst.) 
of Forbes. It seems therefore perfectly justifiable to reconstruct the 
genus Bougainvillia in such a way as to separate from it those species 
which have a long, slender digestive cavity, with but slightly branching 
tentacles, under the name of Margelis. 

The oral tentacles are, in the youngest Medusso (Fig. 244), small, 

Fig. 244. Young Margelis, having only two marginal tentacles at the base of each chymiferous 
tube, and simple oral tentacles. 

Fig. 245. young Margelis, seen from the abac tin al pole, in the condition of Fig. 244. 



158 



MARGELIS CAROLINENSIS. 



Fig. 246. 



simple tentacles, terminating with a cluster of lasso-cells ; in somewhat 
older Medusas the oral tentacles have two branches, as in Fig. 246, 
when there are six tentacles to each marginal bulb, with a small bundle 
of lasso-cells at the extremity. As the young Medusa grows, the bell 

loses its conical shape, and becomes more spherical. 
The marginal tentacles of the young are carried 
curved inwards towards the veil ; as they increase 
in length they lose this tendency, and are stretched 
out in every direction. The additional tentacles are 
added at the base of the conical bulb, those which 
are near the apex being always the longest and 
oldest. 

The Hydrarium (Fig. 247) grows to a very large 
size, from eight to twelve inches in height ; it re- 
sembles in its general mode of branching Eudendrium ramosum. The 
main stem is stout, and tapers gradually ; the main branches begin 
close to the root, and thus form clusters of stems, from which branch 
off irregularly secondary branches, which are quite slender, and ramify 
but little. The Hydra? are very large, and quite closely packed to- 
gether, growing with equal profusion on the main stem and on the 




Fig. 217. 



Fig. 248. 





branches. The Hydrarium is found growing attached to Fucus vesicu- 
losus in great abundance. The general color of the main stem is some- 
what grayish green, the Hydraa are of a delicate rosy tint. The Me- 
dusaa buds are developed, somewhat as in our Bougainmllia superdlir 
aris, along the stem (Fig. 248), without, however, being limited to the 
proximity of the Hydra head, as the Medusae make their appearance 

Fig. 246. Proboscis of a Margelis, having already six tentacles at each sensitive bulb. 
Fig. 247. Hydrarium of Margelis carolinensis, greatly reduced in size. 
Fig. 248. Magnified heads and Medusae buds of Margelis carolinensis. 



EUDENDRIUM. 159 

all over the stem, resembling in this respect very strikingly the Peri- 
gonimus of Sars, to which the Hydrarium also bears a close affinity, 
from the size of its sterile Polypes. 

Charleston Harbor (McCrady) ; Buzzard's Bay, Naushon (A. Agassiz). 

Cat. No. 43, Naushon, Mass., Sept. 1861, A. Agassiz. Hydrarium. 

Cat. No. 437, Naushon, Mass., 1864, A. Agassiz. Medusa. 



EUDENDRIUM EHRENB. 

Eudendrium EHRENB. Corall. d. Roth. Meeres. 1834. 
Eudendrium AGASS. Cont. Nat. Hist, U. S., IV. p. 342. 1862. 
Calamella OKEN. Lehrb. der Naturg. Gesch. 1815. 
Thoa LAMX. Pol. Cor. Flex. 1816. 



Eudendrium. dispar AGASS. 

Eudendrium dispar AGASS. Cont. Nat. Hist. U. S., IV. pp. 285, 289, 342, Fig. 36 ; PL 27, Figs. 

10-21. 1862. 
Thoa dispar AGASS. Cont. Nat. Hist. U. S., IV. PL 27, Figs. 10-16. 1862. 

This Hydroid (Fig. 249) is closely allied to the 
Tubularia ramea of Dalyell and the Coryne pu- 
silla var. muscoides of Johnston. The male and 
female communities are readily recognized by the 
different color of the Medusas buds ; the male Me- 
dusae buds are bright orange, while the females 
are of a dull pink. 

Massachusetts Bay (Agassiz). 

Cat. No. 34, Nahant, Mass., Sept. 1854, H. J. Clark. Hydrarium. 

Cat. No. 35, Suisconset, Mass., July, 1849, L. Agassiz. Hydrarium. 

Cat. No. 36, Nahant, July, 1861, A. Agassiz. Hydrarium. 

Cat. No. 37, Nahant, July 11, 1861, A. Agassiz. " 

Cat. No. 38, Naushon, Mass., September, 1861, A. Agassiz. 

Cat. No. 405, Nahant, June, 1862, A. Agassiz. Hydromedusarium. 

Cat. No. 423, Eastport, Me., A. E. Verrill. 

Museum Diagram No. 23. 

Fig. 249. Female Medusae buds in different stages of development. 




160 



EUDENDRIUM RAMOSUM. 



Eudendrium tenue A. AGASS. 

Fis - 250 - This species (Fig. 250) can at 

once be distinguished from the 
E. dispar Agass. (Fig. 249) by 
its large clusters of Medusae, 
while in the E. dispar the Me- 
dusae buds are always somewhat 
scattered, and never clustered to- 
gether, as in E, tenue. This is 
quite a small species, the tallest 
specimens hardly rising more than 
an inch to an inch and a half, 
while the E. dispar is a large 
Hydroid, growing in tall steins, 
branching but little; the E. tenue, 
on the contrary, forms small colo- 
nies of densely crowded individ- 
uals, branching profusely. The color is light pinkish. 

Massachusetts Bay, Nahant (A. Agassiz) ; Buzzard's Bay, Naushon 
(A. Agassiz). 

Cat. No. 39, Naushon, Sept. 1861, A. Agassiz. Hydrarium. 

Cat. No. 40, Suisconset, July, 1849, L. Agassiz. Hydrarium. 

Cat. No. 41, Suisconset, July, 1849, L. Agassiz. Hydrarium. 

Cat. No. 402, Nahant, June 17, 1862, A. Agassiz. Hydromedusarium. 




Eudendrium ramosum McCR. 

Eudendrium ramosum McCR. Gymn. Charleston Harbor, p. 64. 
? Eudendrium ramosum JOHNST. Brit. Zooph., p. 46. 

McCracly has identified this species with the English E. ramosum 
Johnst. Specimens collected at Charleston by Professor Clark cer- 
tainly show a great similarity to the English species, but it still 
remains to be proved, as we do not know their development, that 
these species are identical. 

Charleston, S. C. (McCrady). 

Cat. No. 42 Charleston, S. C., December, 1861, H. J. Clark. 



Fig. 250. A part of a male colony ; magnified. 



LIZZIA. 



LIZZIA FORBES. 

Lizzia FORBES. Brit. Naked-eyed Medusae, p. 64. 1848. 
Lizzia AGASS. Cont. Nat. Hist. U. S., IV. p. 345. 1862. 
Cytceis SARS (non Esch.). Beskriv., p. 28. 1835. 



Lizzia grata A. AGASS. 

Lizzia grata A. AGASS.; in Proc. Bost. Soc. Nat. Hist,, p. 100, Figs. 28, 29. 1862. 

The presence of a cluster of tentacles, intermediate between the 
chymiferous tubes gives to Lizzia a totally different aspect from that 
of Bougainvillia, which is the permanent embryonic type of Lizzia. 
In a young Lizzia this middle cluster is wanting ; the character of the 
development of the tentacles is totally different from that of Bougain- 
villia ; we have an odd tentacle at first (Fig. 252), and then pairs of 

Fig. 251. 

BBHHH 

Fig. 252. n mA Fig . 253 . 






tentacles (Fig. 253), while in the Bougainvillia we have, for the first 
set, as well as for the subsequent cycles, a pair of tentacles ; so that we 
may have, as members of the same family, forms in which these clus- 
ters are reduced to a minimum, as in Dysmorphosa (Fig. 259), where 
the odd tentacle alone is developed. 

In an adult Lizzia (Fig. 251) the chymiferous cluster of tentacles 
consists of five, the intermediate cluster of three. The order of succes- 
sion of the different tentacles in the young stages can easily be traced 
in Fig. 252 ; at first there are four long tentacles opposite the chymif- 
erous tubes, flanked by two short tentacles ; next the odd tentacle of 
the middle cluster makes its appearance, and then after some time the 
other pair of tentacles of the middle cluster. The sensitive bulb of the 
adult is elongated, polygonal, and thickly covered with pigmentrcells 
(2), Fig. 253) ; the digestive cavity of the adult (Fig. 254) is nearly as 
long as the cavity of the bell, into which a short projection of the bell 

Fig. 251. Adult male Lizzia grata, seen in profile ; magnified. 

Fig. 252. Quarter of the disk of a young Lizzia. 

Fig. 253. Magnified view of the sensitive bulb, p, pigment-cells. 
NO. II. 21 



162 



LIZZIA GRATA. 



extends ; the genital pouches are on the sides of the digestive cavity, 
extending nearly to its extremity. The actinostome terminates in four 
large lobes, edged with short oral tentacles, surmounted by a knob of 



Fig. 254. 



Fig. 255. 





lasso-cells ; these lips are quite expansive and contractile, (t, t', t", t'", 
Fig. 255.) In the young Medusae the digestive cavity terminates with 
only four club-shaped tentacles (t, Fig. 256) ; this soon branches in 



Fig. 256. 






somewhat older stages, as that of Fig. 252, and assumes the shape of 
Figs. 257, 258, t, additional club-shaped oral tentacles being added in 
the order in which they are numbered in Fig. 255. 

Massachusetts Bay (A. Agassiz). 

Cat. No. 446, Nahant, A. Agassiz. Medusa. 

Fig. 254. Proboscis of male Lizzia ; magnified. 

Fig. 255. One of the four lobes of the actinostome, seen from above. /, t, t 1 , t", t"', tentacles 
of actinostome. 

Fig. 256. Actinal view of the proboscis of a young Lizzia. t, oral tentacle ; </, digestive cavity. 

Fig. 257. Actinal view of proboscis of an older specimen, a, actinostome ; g, genital pouches ; 
<, tentacles of actinostome. 

Fig. 258. Abactinal view of Fig. 257, somewhat less magnified, with the oral tentacles in a 
different attitude ; lettering as above. 



DYSMORPHOSA. 



DYSMORPHOSA PHIL. 

Dysnwrpliosa PHIL.; in Archiv f. Nat., p. 37. 1842. 
Podocoryne SARS. Fauna Lit., p. 4. 184G. 

Sars lias traced the development of a Medusa from Podocoryne 
carnea which is very closely allied to Dysmorphosa fiilyurans here 
figured. It corresponds, in its younger stages, while still attached to 
the proboscis of its parent, to the different stages of our Medusa, in the 
number, arrangement, and order of appearance of the tentacles, so com- 
pletely, that I have referred it to the genus Dysmorphosa of Philippi, 
considered by Sars as identical with the Hydroid from which his 
Medusa was developed. This identification is the more probable, as 
Krohn has given us a complement to the observations of Sars on the 
adult Medusae, and traced the budding from the proboscis in exactly 
the same manner as it is here given. The Lizzia figured by Claparede 
in the tenth volume of Siebold u. Kolliker's Zeitschrift, in which he has 
also traced the budding from the proboscis, appears to be identical with 
the Podocoryne carnea of Sars. 

Dysmorphosa fulgurans A. AGASS. 

This Medusa (Fig. 259) is sometimes so abundant that the whole sea, 
when disturbed, is brilliantly lighted by the peculiar bluish phosphores- 
cent color which they give out. Their great number is easily accounted 
for by their mode of reproduction and by its rapidity. Young Medusa? 
are formed by budding on the upper extremity of the proboscis (Figs. 
259, 260), and their development takes place in the course of three or 



Fig. 259. Fig. 260. 





four days ; from three to four Medusae develop at the same time ; the 
Medusas buds of the third generation are already forming, while the 
second is still attached. (Fig. 260.) The young Dysmorphosa has at 
first four tentacles, the middle set developing later ; there are only four 
oral tentacles, quite long and slender, and an accumulation of pigment- 
Fig. 259. Adult Dysmorphosa ; magnified. 
Fig. 2CO. Magnified proboscis, showing young Medusae of the second and third generations. 



164 NUCLEIFEILE. 

cells at the base of the tentacles ; the abactinal part of the bell is quite 
conical (Fig. 259) ; the tentacles of the adult Medusa are usually car- 
ried rather stiffly (Fig. 260) ; but when the young Medusa is still at- 
tached, they are frequently expanded several times the diameter of 
the bell. (Fig. 260.) This Medusa resembles very much the young of 
Turritopsis nutricula, and could readily be mistaken for it. It would 
be most natural, therefore, to place this genus in the family of Nuclei- 
fera3 ; but the presence of the peculiar oral tentacles of Lizzia, added 
to the fact that this is probably only a permanent embryonic stage of 
Lizzia, induces me to place it among the Bougainvillida?. 

Allman describes, in the fourth volume of the Ann. & Mag. of N. H. 
for 1859, page 368, a Medusa as developing from Laomedea temds, 
which resembles so strikingly Lizzia and Dysmorphosa that I suspect 
there must be some error in his observation. Does it not rather come 
from his Dycoryne stricta, which he found at the same time and at the 
same place, and which would thus bring this Medusa, intermediate in 
its characters between Lizzia and Dysmorphosa, to its proper place 
among the BougainvillidaB ? 

Massachusetts Bay, Nahant (A. Agassiz) ; Buzzard's Bay, Naushon 
(A. Agassiz). 



Family NUCLEIFERjE Less. 

Nucleifene LESS. Prod. Mon. Mecl. 1837. 

Nucleifercn AGASS. Cont. Nat. Hist. U. S., IV. p. 346. 18G2. 

Oceaniihe Escn. (j;. p. non Agass.). Syst. der Acal., p. 96. 1829 

Oceanidce GEGEXB.; in Zeitschrift f. Wiss. Zool., p. 219. 1856. 

Oceanidce McCR. Gymn. Charleston Harbor, p. 21. 

Cfactda 1 McC-R. Gymn. Charleston Harbor, p. 37. 

Claoidas AGASS. Cont. Nat. Hist. U. S., IV. p. 338. 1862. 



TURRIS LESS. 

Tunis LESS. Prod. Mon. Med. 1837. 

Tunis AGASS. Cont. Nat. Hist. U. S., IV. p. 346. 1862. 

Oceania AUCT. (p. p. non Agass.). Medusa. 

Clavula WRIGHT. Hydra. 

Turris vesicaria A. AGASS. 

Turris vesicaria A. AGASS. ; in Proc. Bost. Soc. Nat. Hist., IX. p. 97. 

This Medusa I formerly supposed to be the Medusa digitalis of 
Fabricius ; it certainly is not tlmt of Forbes. Since that time I have 
ascertained that the Medusa digitalis of Fabricius belongs to a dif- 
ferent family, the TrachynemidaB. (See page 57.) It has been found 
but once at Nahant, in the early part of the spring, and probably 



TURRIS VESICARIA. 



165 



having habits similar to those of Tinia, it is only accidentally met 
with. It has very much the same kind of coloring as our Tima, but 
in Turns the color of the genital organs and the base of the tenta- 
cles is somewhat more yellowish. The bell of Tunis is exceedingly 



Fig. 261 




Fig. 262. 




thin, except at the abactinal pole (Fig. 261), where it forms a sort 
of bladder, capable of more or less contraction at its base ; when the 
Medusa is disturbed, the sides of the bell, below the bladder, contract, 
and give it a polygonal outline, as is seen in Fig. 262. The genital 




Fig. 264. 




organs remind us somewhat of those of Ptychogena, only they are 
attached to the abactinal part of the interior of the bell ; passing in 

Fig. 261. Turris vcsicaria, natural size ; seen in profile. 

Fig. 2G2. The same, with the bell contracted. 

Fig. 263. A portion of the disk, seen from the abactinal pole, a, opening of actinostome ; y, 
point of attachment of the convoluted genital organs to the inner surface of the bell ; c, chymifer- 
ous tubes ; c', continuation of convolution of genital organs, forming the sides of the chymiferous 
tubes. 

Fig. 264. Magnified profile view of genital organs and actinostome. /, lips of actinostome ; 
#', convoluted genital organs, extending from one side of the bell to the other ; y, part of the geni- 
tal organ on the other side of the chymiferous tube ; c', as in Fig. 263 ; r, base of bladder sur- 



mounting the bell. 



166 



TURRIS VESICARIA. 



deep festoons (Fig. 263) from one chymiferous tube to another; they 
form a compact mass, and fill the whole of the upper part of the bell ; 
from this are suspended four movable, deeply-frilled lips (/, Fig. 264), 
leading into a short digestive cavity totally concealed by the genital 
organs. The chymiferous tubes are broad and very flat, the two edges 
of the tubes being irregularly cut (Fig. 265) ; transverse folds extend 
from one side to the other ; the chymiferous tubes open into a 
broad circular tube (Fig. 266), having a similar hacked edge ; with 
the circular tube communicate five tentacles placed between the chy- 
miferous tubes, and one opposite each. The tentacles are broad at the 
base, and taper very rapidly into a long slender lash ; at the base of 



Fig. 266. 




Fig 265. 



Fig. 267. 





Fig. 268. 




the bag of the tentacles is a large swelling, in the centre of which is 
placed a distinct eye-speck. (Figs. 266, e ; 267, 268.) The size of 
the opening, leading from the circular tube to the tentacle, is readily 
seen when examined from the abactinal side. (Figs. 263 ; o, 268.) 
In the genera Tunis, Ptychogena, Olindias of Miiller, and Polyorchis, 
we have strongly developed characters, which show their close rela- 
tion ; in Turns and Ptychogena, the nature of the genital organs and 
the character of the chymiferous tubes ; in Olindias and Polyorchis, 
the genital organs and branching tubes, being simply extreme cases 
of what we have first hinted at in Turns, more strongly marked in 
Ptychogena, in the mode of attachment of the genital organs, and 

Fig. 2G5. Magnified view of a part of a chymiferous tube. 

Fig. 266. Base of one of the chymiferous tubes, and part of the circular tube, c, chymiferous 
tube; c 1 ', circular tube; b, sensitive bulb of tentacle; e, eye-speck; /, lash of the tentacles cov- 
ered with lasso-cells. 

Fig. 26 7. One of the tentacles in a semi-profile view. 

Fig. 268. One of the tentacles, seen from the abactinal pole, o, opening leading from circular 
tube. 



TURRITOPSIS. 167 

carried out in a very different direction in the genital pouches on the 
pendent proboscis of Stomotoca. 

Massachusetts Bay, Nahant (A. Agassiz). 

Cat. No. 274, Nahant, Mass., May 12, 1862, A. Agassiz. 



TURRITOPSIS McCR. 

Turritopsis McCR. Gymnoph. Charleston Harbor, p. 24. 1857. 
Turritopsis McCR. On Turritopsis, new species, .... p. 2. 1856. 
Turritopsis AGASS. Cont. Nat. Hist. U. S., IV. p. 347. 1862. 




Turritopsis nutricula 

Turritopsis nutricula McCn. Gymn. Charleston Harbor, p. 25, Pis. 4, 5, 8, Fig. 1. 
Turritopsis nutricula AGASS. Cont. Nat. Hist. U. S., IV. p. 347. 1862. 
Turritopsis nutricula A. AGASS. ; in Proc. Boston Soc. Nat. Hist., IX. Figs. 22, 23. 

The young Medusae have only four stiff tentacles, with a long bottle- 
shaped digestive trunk (Fig. 269), fastened by its base to the lower 
part of a short prolongation of the bell, along rig. 259. 

w r hich the chymiferous tubes run ; the digestive 
cavity has four marked prolongations, surmounted 
by bunches of lasso-cells ; along the upper part 
of the digestive cavity, the genital organs are 
developed in four bunches, placed along the pro- 
longations of the actinostome. As the Medusae increase in size, there 
are four more tentacles formed, one in the middle of the space between 
the chymiferous tubes ; the genital organs increase in length, and by 
the time two additional tentacles (3, Fig. 270) have been formed, one 
on each side of the tentacles of the second cycle, the genital glands 
have become very much swollen, and occupy nearly the whole length 
of the digestive cavity and proboscis. With Fig. 270. 

advancing size the gelatinous mass loses its 
bell shape, and becomes more globular, the 
tentacles (then sixteen in number) losing 
somewhat their stiffness ; when it has only 
four tentacles, the young Medusa resembles 
so much Sarsia, in the shape of the bell and 
of the digestive cavity, that were it not that 
Sarsia carries its tentacles curled up close to the circular tube, while 
in Turritopsis they stand stiffly out from the rim of the bell, like the 
tentacles of Eudendrium, it would be difficult to distinguish them apart. 
Not having traced this Medusa beyond the stage when it had sixteen 

Fig. 269. Young Turritopsis nutricula, with four marginal tentacles ; greatly magnified. 
Fig. 270. Somewhat more advanced Turritopsis, having sixteen tentacles. 




168 STOMOTOCA. 

tentacles, I am unable to determine whether it is a distinct species 
from the Turritopsis of Charleston ; the color of the proboscis and of 
the sensitive bulb is different in the two ; the ovaries are light brown, 
with darker lines in the furrows between them ; the ocelli are dark- 
red brown. The shape of the tentacles and of the bell, however, are 
the same in both, as well as their habits, and the changes which this 
Medusa goes through with advancing age. From each side of the 
base of the four tentacles, at the junction of the circular and of the 
chymiferous tubes, runs a thread of bunches of lasso-cells, which reach 
nearly to the abactinal pole, as in the young Medusse of many of the 
Tubularians. 

There is found at Nahant the young of a species of Turritopsis which 
differs from the Turrit^isis nutricula very essentially ; the bell, which 
is remarkably thin, has a uniform thickness from the circular tube to 
the abactinal pole ; the tentacles, even when there are only four, are 
quite long, slender, and usually carried curled up along the sides of 
the bell, giving these young Medusae a totally different aspect from the 
young of the T. nutricula. I might mention here that the trace of its 
connection with a Hydroid stock was very distinct in young Medusas ; 
the adult Medusa was not observed. 

Charleston, S. C. (McCrady) ; Naushon, Buzzard's Bay (A. Agassiz). 

Cat. No. 273, Naushon, September, 1861, A. Agassiz. Medusa. 

Cat. No. 440, Naushon, July, 1864, A. Agassiz. Medusa; 



STOMOTOCA AGASS. 

Siomotoca AGASS. Cont. Nat. Hist. U. S., IV. p. 347. 1862. 

Saphenia FORBES (non Esch.). British Naked-eyed Medusae, p. 25. 1848. 

Stomotoca apicata AGASS. 

Stomoloca apicata AGASS. Cont. Nat. Hist. U. S., IV. p. 347. 1862. 
Suphenia apicata McCu. Gymn. Charleston Harbor, p. 27, PI. 8, Figs. 2, 3. 

Charleston, S. C. (McCrady) ; Newport (A. Agassiz). 
Cat. No. 454, Newport, A. Agassiz. Medusa. 

Stomotoca atra AGASS. 

Stomotoca atra A. AGASS.; in Agassiz's Cont. Nat. Hist. U. S., IV. p. 347. 1862. 

This Medusa (Fig. 271) is much larger than the one Forbes has de- 
scribed as S. dinema (Naked-eyed Medusa?, PI. II. Fig. 4), which meas- 
ures only a quarter of an inch, while this species is from three quarters 
to an inch in size ; it is much less elongated, the vertical and horizontal 
diameters being the same ; it swells out to its greatest horizontal chain- 



STOMOTOCA ATRA. 



109 



eter almost immediately above the circular tube, where it curves in 
slightly, and then bends uniformly towards the abactinal pole ; the 
upper part is almost hemispherical, being very blunt at the abactinal 
pole ; the peduncle tapers gradually from the base to the ovaries ; 
the ovaries are barrel-shaped, extending to the digestive cavity, which 
is small at the point where the chymiferous tubes empty into it, but 
gradually bulges out, and passes into the lobes of the actinostome, 
where it is three or four times as wide as at the base. Only two of 
the chymiferous tubes have long tentacles ; between these larger tenta- 
cles there are a number of small tentacles (in the specimen described 
about eighty), hardly one sixteenth of an inch long. The ovaries are 
placed on the abactinal extremity of a long peduncle ; they consist of 
a double series of folds, occupying the middle third of the peduncle 
(Fig. 272), and are of a dark-brown color; below them is placed the 
digestive cavity, which is very contractile, of a lighter color, and end- 



ig. 271. 




Fig. 273. 




Fig 272. 




ing with an actinostome divided into four lips. While swimming, these 
Medusae move slowly, contracting alternately either one or the other of 
their long tentacles ; when contracted, the tentacle has very much the 
appearance of the contracted tentacle of a Pleurobrachia ; when floating 
about motionless, the chymiferous tubes often contract, and this gives 
to the Medusa the appearance of being deeply lobed (Fig. 273), the 
intermediate portions of the periphery not seeming to be so highly 
contractile as that which immediately adjoins the chymiferous tubes. 
This Medusa was quite common in the Straits of Eosario, W. T., in the 
beginning of June. I also found specimens of it during the summer, 
till September, in different parts of the Gulf of Georgia, and in the 
neighborhood of Port Townsend. 

Gulf of Georgia, W. T. (A. Agassiz). 

Cat. No. 50, Straits of Rosario, W. T., June, 1859, A. Agassiz. Medusa. 

Fig. 271. Stomotoca atra, somewhat magnified ; seen in profile. 
Fig. 272. Magnified view of genital organs. 
Fig. 273. Stomotoca atra, in a different attitude. 



NO. II. 



22 



170 



RHIZOGETON. 



RHIZOGETON AGASS. 

Rhizogeton AGASS. Cont. Nat. Hist. U. S., IV. p. 347. 1862. 

Rhizogeton fusiformis AGASS. 

RMzogeton fusiformis AGASS. Cont. Nat. Hist. U. S., IV. pp. 224, 347, PI. 20, Figs. 1 7 - 23. 1862. 

Massachusetts Bay (Agassiz). 

Cat. No. 52, Nahant, Mass., July, 1861, A. Agassiz. Hydrarium. 



CLAVA GMELIN. 

Clava GMELIN ; in Beschaft. d. Berlin. Ges. Naturf. Freunde. 1775. 



274. 




Clava leptostyla AGASS. 

Clava leptottyla AGASS. Cont. Nat. Hist. U. S., IV. pp. 218, 222, 
Fig. 32 ; 338, PI. 20, Figs. 11-16*; PI. 21. 1862. 

Clava multicornis STIMPS. Mar. Inv. Grand Manan, p. 11. 1853. 

Clava multicornis LEIDY. Mar. Inv. Rhode Island and New Jersey, 
p. 3, PI. XI. Figs. 33, 34. 1855. 

Clava multicornis PACK. ; in Can. Nat. & Geol. Dec. 1863. 

The Clava leptostyla (Fig. 274) seems to differ 
from the C. multicornis by the greater number of 
its tentacles. 

Point Judith (Leidy) ; Massachusetts Bay (Ag- 
assiz). 

Cat. No. 51, Kingston, Mass., July, 1851, H. J. 
Clark. 

Cat. No. 451, Nahant, Mass., A. Agassiz. Hydro- 
medusarium. 

Museum Diagram, No. 24, after L. Agassiz. 

Fig. 274. Clava leptostyla ; greatly magnified. 



WILLIAD.E. 



Family WILLIAD^E Forbes. 

Williadce FORBES. British Naked-eyed Medusas, p. 19. 1848. 

Berenicidce AGASS. (p. p. non Esch.). Cont. Nat. Hist. U. S., IV. p. 345. 1862. 



WILLIA FORBES. 

TH/Ma FORBES. British Naked-eyed Medusae, p. 19. 1848. 
Willia AGASS. Cont. Nat. Hist. U. S., IV. p. 346. 1862. 



Willia ornata McCu. 

Willia ornata MCR. Gymnoph. Charleston Harbor, p. 47, PI. 9, Figs. 9-11. 

Willia ornata AGASS. Cont. Nat. Hist. U. S., IV. p. 346. 1862. 

Willia ornata A. AGASS. ; in Proc. Bost. Soc. Nat. Hist., IX. Figs. 20, 21. 1862. 

The development of Willia presents some striking differences from 
the mode in which tentacles are regularly developed in successive cy- 
cles among Polyps, and from what has been observed, in accordance 
with that mode of development, among some of our naked-eyed Me- 
dusse (Laomedea diaphcma, Clytia bicophora, etc.). In very young 
Willioe, having only four simple chymiferous tubes and four tenta- 
cles, two much longer than the others, as we find them in Atractylis 
and Lafoea, there are soon developed four additional tentacles ; these 

Fig. 274". Fig. 275. 





do not appear in the middle between the adjoining chymiferous tubes, 
but about one third of the distance. (Fig. 274 a .) When this second 
cycle of tentacles can be readily distinguished as four well-marked 
knobs along the circular tube, an offset branches off from the sim- 
ple chymiferous tube, which soon extends to the circular tube, oppo- 
site the rudimentary tentacle ; this offset takes its origin at two thirds 
the length of the chymiferous tube from the circular tube ; at the same 
time this branch is forming, the main tube is slightly bent in the op- 
posite* direction from that in which the branch diverges ; the offset 

Fig. 274 a . Youngest Willia observed, having only the second set of tentacles developed. 2, 
second set of marginal tentacles ; 2e, branch of chymiferous tubes leading to them. 

Fig. 275. A young Willia, nearly in the stage of Fig. 276, seen from the abactinal pole. 3, 
third set of tentacles ; 3 C , chymiferous tube leading to them. 



172 



WTLLIA ORNATA. 



also is slightly convex, the convexity being turned towards the circular 
tube. The next cycle, the third, consists only of four tentacles, which 
all make their appearance on the other side of the main chymiferous 
tube, just as far on the other side as the tentacles of the second 
cycle were on this side of the main radiating tube ; the offsets of 
the tube which reach these tentacles start slightly below the first, and 



Fi" 276. 




are likewise bent towards the circular tube. I was not able to observe 
the formation of the additional branches and tentacles. I refer this 
species at*present to the Willia ornata of McCrady found at Charleston, 
the specimens which I found (Fig. 276) not being advanced enough to 
enable me to determine their difference or identity. The tubes which 
contain the clusters "o|* lasso-cells (7, Fig. 279), running in the thickness 




Fig. 278. 



Fig. 279. 





of the spherosome from the circular tube to the height of the base of 
the digestive cavity, were particularly well defined ; the longer tubes, 
extending in the middle of the space between two chymiferous tubes, 
contain three clusters of lasso-cells, made up of from four to five large 
cells arranged in a circle. Even at this early stage the ovaries were 
well developed (Figs. 277, 278) ; they are elliptical bunches placed on 

Fig. 276. Profile view of a young AVillia ; magnified. 

Fig. 277. Part of the circular tube. Z, tubes running into the thickness of the spherosome, 
containing large lasso-cells. 

Fig. 278. View of ovary of Fig. 276. 

Fig. 279. The same as Fig. 278, seen from the abactinal pole. 



PROBOSCIDACTYLA. 173 

both sides of the cross-shaped edges of the digestive cavity, giving it a 
quadrangular appearance, when seen from above. (Fig. 279.) Found 
at Naushoii the last part of September, one tenth to one eighth of an 
inch in diameter. 

Charleston Harbor (McCrady) ; Buzzard's Bay, Naushon (A. Agassiz). 



PROBOSCIDACTYLA BRANDT. 

Probnscirtach/la BRANDT ; in Mem. Acad. St. Petersburg, IT. p. 228. 1835. 
Proboscidactyla AGASS. Cont. Nat. Hist. U. S., IV. p. 346. 1862. 

Proboscidactyla differs from Willia in the mode of branching of the 
chymiferous tubes ; in the former genus each main chymiferous tube 
divides into two halves, branching symmetrically on both sides from, 
the two main branches, which is not the case in Willia. 



Proboscidactyla flavicirrata BR. 

ProboscMactyla favicirrala BR. ; in Mem. Acad. St. Petersb., p. 390, PI. 19. 1838. 
Proboscidactyla flavicirrata AGASS. Cont. Nat. Hist. U. S., IV. p. 346. 1864. 

This small Medusa seems quite uncommon in the Gulf of Georgia. 
I only found a couple of specimens, in the lat- Fig 280> 

ter part of June, near Galiano Island. They 
are so small and so transparent that it requires 
the utmost attention to discover them. It seems 
to be the species found by Brandt on the coast 
of Kamtschatka ; he was unable to find any 
actinostome in the trunk-like prolongation (Fig. 
280), which he represents as surrounded by a 
large number of small tentacles ; the digestive 
cavity opens by an actinostome, surrounded 
by four large lobes, and these subdivide into a 
number of smaller lobes, subordinate to the larger ones. (Fig. 281.) 
The ovaries are attached to the abactinal extremity of the chymiferous 
tubes, and extend but a short distance towards Fig . 281 . 

the periphery along the four radiating tubes 
(Fig. 281) ; the chymiferous tube runs sin- 
gle for a short distance, before the principal 
division into two branches takes place (&, Fig. 
282) ; at the point of meeting of each of the 
smaller branches with the circular branch, 
there is a very marked eye-speck ; the tentacles are numerous, each 

Fig. 280. Proboscidactyla flavicirrata ; magnified. 





Fig. 281. Actinostome and digestive cavity. 



174 PROBOSCIDACTYLA FLAVICIRRATA. 

chymiferous tube dividing into two main branches, and each branch 
Fig 282 subdividing again into eight, making in all sixty- 

four branching tubes, and as many tentacles and 
eye-specks. Between each of the ocelli there ex- 
tends from the circular tube a small tube pene- 
trating into the thickness of the edge of the 
spherosome, which projects a considerable distance 
beyond the circular tube. The color of the di- 
gestive cavity is dirty yellow, the tentacles are 
of a brilliant straw color, and the ocelli dark blue. 
The whole exterior of the spherosome is densely 
granulated, the projections being probably some- 
thing similar to what we find on the disk of Au- 
relia flamdula, made up of large lasso-cells, only 
much more densely crowded together. The shape 
of the bell is almost perfectly thimble-shaped, 

there being neither bulging nor striking indentations of the periphery. 

The motions of this Medusa are very rapid ; the tentacles are capable 

of but little contraction. 

Petropolawsky (Mertens) ; Gulf of Georgia, W. T. (A. Agassiz). 

Cat. No. 62, Gulf of Georgia, W. T., June, 1859, A. Agassiz. Medusa. 

Fig. 282. Portion of disk, to show the mode of branching, b, first fork ; I, tubes containing 
lasso-cells, as in Willia. 




SARSIAD^E. 



175 



Family SARSIAD^E Forbes. 

Sarsiada; FORBES (res/r. Agass.). Brit. Naked-eyed Medusae, p. 54. 1848. 
Sarsiadce AGASS. Cont. Nat. Hist. U. 8., IV. pp. 184, 217, 339. 1862. 



CORYNE GART. 

Coryne GART.; in Pall. Elen. Zooph. 1774. Hydra. 

Syncoryna EIIREXB. (/). p.). Corall. des Rothen Meeres. 1834. Hydra. 

Ktijmla SARS. Bidrag til Soedyr. Nat. 1829. Hydra. 

Henuia JOIIXST. British Zoophytes, p. 111. 1838. Hydra. 

Coryne AGASS. Cont. Nat. Hist. U. S., IV. p. 339. 18G2. Hydra. 

Sarsia LESS. Zooph. Acal., p. 333. 1843. Medusa. 

Sthenio DU.J. ; in Ann. Sc. Nat. 1845. Medusa. 

Sarsia AGASS.; in Mem. Am. Acad., p. 224. 1849. Medusa. 



Fig. 284. 



Fig. 285. 



Coryne mirabilis AGASS. 

Coryne miralilis AGASS. Cont. Nat. Hist. U. S., IV. pp. 185-217, Figs. 

9-31 ; PI. 20, Figs. 1-9 ; PL 23% Fig. 12 ; III. PL 11, Figs. 14, 

15; Pis. 17-19. 1860-62. 

Sarsia mirabilis AGASS. ; in Mem. Am. Acad., IV. p. 224, Pis. 4, 5. 
Sarsia mirabilis STIMPS. Mar. Inv. Grand Manan, p. 11. 1853. 
Oceania tubulosa GOULD (o Sars). Inv. of Mass., p. 348. 1841. 
Sarsia r/lacialis MORCH ; in Beskviv. af Greenland, p. 95. 1857. 
Tubularia stellifera COUTH.; in Bost. Journ. Nat. Hist., IE. p. 56. 
Tubularia stellifera GOULD. Inv. Mass., p. 350. 1841. 

This Medusa (Figs. 283, 284, 285) is one of the 
earliest visitants of our wharves. The ice has 

scarcely gone from the shores 
when numbers of young Me- 
dusae, just freed from the 
Hydrarium, swarm near the 
surface on any sunny day. 
Captain Couthouy has de- 
scribed, under the name of 
Tubularia stellifera, a Hy- 
droid which is probably the 
Hydroid of our Sarsia mira- 
bilis ; as the specimens from 
which his descriptions were 
made have not been pre- 



Fig. 283. 




Fig. 283. Adult Coryne mirabilis, seen in profile ; one half natural 



size. 



Fig. 284. Coryne mirabilis, with proboscis contracted. (, tentacles ; 
e, veil ; c, circular tube ; o, actinostome. 

Fig. 285. Coryne mirabilis, with expanded proboscis, c/, proboscis ; 
a, ft, thickness of the bell. 



176 



CORYNE ROSARIA. 



served, I am unable to state this positively. It seems to make but 
little difference to the Hydrarium (Figs. 286, 287, 288) or to the 



Fig. 286. 





Fig. 287. 




Medusa whether they live in pure sea water, such as they find at 
Nahant, or live in the more brackish waters of the inner harbor of 
Boston ; they are equally abundant in both localities. 

Massachusetts Bay (L. Agassiz). 

Cat. No. 45, Nahant, Mass., May, 1862, A. Agassiz. Hydromedusarium. 

Cat, No. 60, Nahant, May, 1862, H. J. Clark. Hydrarium. 

Cat. No. 64, Nahant, March, 1862, H. J. Clark. Hydrarium. 

Cat. No. 268, Boston, April, 1862, A. Agassiz. Young Medusas. 

Cat. No. 269, Boston, May, 1862, A. Agassiz. Young Medusas. 

Museum Diagrams, No. 20, 21, after L. Agassiz. 



Coryne rosaria A. AGASS. 

Coryne rosaria A. AGASS. ; in Agassiz's Cont. Nat. Hist. U. S., IV. p. 340. 1862. 

I have but little doubt that the Hydroid here described is the larva 
of Coryne rosaria ; this settles any doubt there may be concerning the 
specific differences between this Medusa, and the European or American 
representatives on the two sides of the Atlantic. The Hydrarium re- 
sembles somewhat Coryne stirjula of Sars, but the proportions of the 
individuals of these two Hydraria are totally different ; what is particu- 
larly characteristic of Coryne stipula is the stoutness and great size of 
the head and stem, compared to the size of the community ; in Coryne 
rosaria the heads, which are quite slender, are supported by remark- 
ably long and attenuated stems ; they branch also very profusely, and 
it is not uncommon to find communities of this graceful Coryne reach- 
ing a height of three to three and a half inches. Medusas buds were 

Fig. 286. Cluster of Ilydraria of Coryne mirabilis. 

Fig. 287. Young Hydrarium. 

Fig. 288. Magnified view of a head with Medusa bud, f/, attached. 




SYNDICTYON. 177 

observed on the Hyclrarium in March ; no young Medusae have been 
observed; the adults attain an enormous size, meas- Fig . 289 _ 

uring more than an inch in polar diameter, as in Fig. 
289, which is drawn the natural size. 

The spherosome bulges very rapidly from the abacti- 
nal pole (Fig. 289) till it reaches the point of junction 
of the chymiferous tubes ; from there it tapers very 
gradually towards the peripheric tube ; the chymiferous 
tubes are exceedingly slender, the digestive cavity very 
long, projecting one half its length beyond the circular 
tube, swelling near the lower extremity, and then sud- 
denly contracting, tapers gradually, in the form of a 
conical projection, beyond the ovaries ; the sensitive 
bulbs are large, the eye-specks small. The proboscis 
and the tentacles are of a dirty-yellow color, the color 
of the swelling of the proboscis and of the sensitive 
bulbs being somewhat darker. It resembles Sarsia 
tubulosa of the English coast more than Sarsia mira- 
btiis of New England. Found in the Straits of Rosario 
in May, and as late as the beginning of July in the 
Gulf of Georgia, W. T. ? and also in the harbor of San Francisco during 
November. 

San Francisco, Cal. (A. Agassiz) ; Gulf of Georgia, W. T. (A. Agassiz). 

Cat. No. 48, Gulf of Georgia, W. T., May, 1859, A. Agassiz. Medusa. 

Cat. No. 49, San Francisco, Cal., March, 1860, A. Agassiz. Hydrome- 
dusariuni. 



SYNDICTYON A. AGASS. 

Syndictyon A. AGASS. ; in Agassiz's Cont. Nat. Hist. U. S., IV. p 340. 1862. 

Syndictyon reticulatum A. AGASS. 

Syndictyon reticulatum A. AGASS. ; in Agassiz's Cont. Nat. Hist. U. S., IV. p. 340. 1862. 

The Hydrarium (Fig. 290) resembles that of Coryne mirabilis ; it is 
much smaller, not being more than one tenth of an inch in height ; it 
does not branch, or only occasionally once, near the base, in very old 
specimens. The stem is slender, the head large, club-shaped, the tenta- 
cles short, eight or ten in number. The Medusae develop among the 
tentacles in the low r er part of the head ; this development is similar to 
that of Sarsia ; when the Medusa is separated it is nearly as large as 
the whole Hydrarium, measuring about one sixteenth of an inch in 

Fig. 289. Coryne rosaria, natural size. 
NO. n. 23 



178 



SYNDICTYON RETICULATUM. 



diameter. The young Medusae resemble somewhat Zanclea (Fig. 291), 
having the lasso-cells of the marginal tentacles arranged spirally in 
large clusters on the surface of the tentacles ; the more advanced 
Medusas lose this character. The bunches of lasso-cells increase in size 
towards the extremity, where the tentacle terminates in a club-shaped 
bunch (Fig. 292) larger than the others; the sensitive bulb is large, the 

Fig. 292. 



Fig. 290. 





Fig. 291. 




ocellus at the base of the tentacle (Fig. 293) is similar to that of Sarsia, 
the spherosome is of a uniform thickness, and the proboscis (Fig. 294) 
resembles somewhat that of Dipurena ; the whole surface of the sphero- 
some is covered with clusters of large lasso-cells (Fig. 296), giving 
it a granulated appearance ; the ground-work consists of minute gran- 
ulation, which appears under a low magnifying power to be arranged 




Fig. 294. 



Fig. 295. 





Fig. 290. Hydromedusarium of Syndictyon reticulatum, greatly magnified. 
Fig. 291. Syndictyon reticulatmu, immediately after it has become freed from the Hydrome- 
dusarium ; in profile, magnified. 

Fig. 292. One of the tentacles of Fig. 291, magnified. 

Fig. 293. Sensitive bulb of Fig. 291. 

Fig. 294. Digestive cavity of Fig. 291. 

Fig. 295. Fig. 291, from the actinal side. 




SYNDICTYON RETICULATUM. 179 

in rows parallel to the circular tube, upon which are scattered large 
lasso-cells. The actinal and polar axes are of about the same length ; 
the veil is well developed (Fig. 295) ; the central part of the sphero- 
some is uniformly arched outside ; the curve of the inner cavity is 
concentric with it ; the proboscis extends somewhat Fig . 236- 

more than half the length of the height of the cav- 
ity of the bell ; the circular and chymiferous tubes 
are narrow (Fig. 296), of uniform diameter through- 
out ; the sensitive bulb is ovoid, with a well-defined 
lenticular-shaped concentration of black pigment- 
cells (Fig. 293) ; the bulb itself is colored light- 
brown ; the walls of the tentacles are thick, the 
tentacular tube tapering rapidly as it nears the ex- 
tremity of the tentacle, where the walls increase in 
thickness in proportion as the tube diminishes in bore ; the bunches 
of lasso-cells begin at some distance from the base of the tentacle (one 
fourth of the length of the tentacle), increase rapidly in size, being 
packed closer and closer towards the extremity of the tentacle, where 
they are large crescent-shaped masses, almost touching each other, and 
composed of very elongated lasso-cells. (See Fig. 292.) The tentacles 
are not very contractile ; usually they are about as long as the vertical 
diameter of the bell, and I have seen them contracted to about half 
that length ; the peduncle is not contractile. The large lasso-cells of 
the surface of the spherosome (Fig. 297) are round ; they are usually 
scattered singly over the whole surface, while the fine granulation of 
the surface of the bell consists of long, narrow cells, 
dividing into smaller granules, which are small, un- 
developed lasso-cells, forming a net-work over the 
surface of the spherosome ; the lasso-cells are not 
as numerous near the abactinal pole as towards 
the margin of the bell, above the circular tube. 
The motions of the Medusa are similar to those 
of Sarsia, the bell, owing to its thinness, being, 
however, much more flexible. The bell has a 
very light metallic-blue tinge. The Hydroid was found growing on 
Diphasia rosacea. Young Medusa?, similar to those developed from 
the Hydroid, are found swimming freely about during June and 
July. 

The young Medusa described above gradually loses the characters 
which distinguished it from Sarsia, and as it becomes more advanced, 
it resembles so closely Sarsia, that were it not for the invariable 

Fig. 29G. Fit;. 291, from the abactinal pole. 

Fig. 297. Part of net-work of the surface of the spherosome. c, large lasso-cells; c', cluster 
of smaller ones. 




180 DIPURENA. 

presence of the light reddish-brown eye-specks, which become red in 
the adult, it would be difficult, without very close examination, to 
distinguish them apart. The tentacles of the adult (Fig. 298) are 
not as long as those of Sarsia ; they are likewise capable of much 
greater contraction, being often carried in a club-shaped form, not 
longer than half the vertical axis of the bell. (Fig. 299.) The acti- 
nostome is also very different ; the lips (four in number) are quite 
prominent (a, Fig. 300), though often carried in trumpet fashion, at 

Fig 298. 
Fig. 299. B 

MHWI ^^K^HSi^^BH 

Fig. 300. 






the extremity of the digestive cavity (a, Fig. 300), and the spherosome 
increases greatly in thickness at the abactinal pole. 

Massachusetts Bay, Nahant (A. Agassiz). 

Cat. No. 160, Nahant, Mass., July, 1861, A. Agassiz. Hydromedusa- 
rium. 

Cat. No. 348, Boston Harbor, May, 1862, H. J. Clark. Medusa. 

Cat. No. 378, Nahant, 1863, A. Agassiz. Medusa. 



DIPURENA McCR. 

Dipurena McCn. Gymn. Charleston Harbor, p. 33. 
Dipurena Ac ASS. Cont. Nat. Hist. U. S., IV. p. 341. 1862. 

McCrady established this genus from an investigation of two species 
of Medusae, which, though having all the characteristics of Slabberia of 
Forbes, yet differed from it in the position of the sexual organs, which 
are placed in Dipurena along the digestive trunk, as in Sarsia and the 
like, w r hile in Slabberia Forbes has figured genital organs along the 

Fig. 298. Adult Medusa, in a natural attitude. 

Fig. 299. The same Medusa as Fig. 298, with the tentacles contracted. 

Fig. 300. Actinostouie of adult Medusa, a, when protruded, trumpet-shape ; a', showing the 
lips of actinostome. 



DIPURENA CONICA. 



chymiferous tubes. This is so contrary to what we have thus far found 
to be uniformly the position of these organs among Tubularian Medusae, 
that there is probably some mistake in Forbes's drawing. 



Dipurena strangulata McCR. 

Dipurena strangnlata McCR. Gymnoph. of Charleston Harbor, p. 33, PI. 9, Fig. 1. 
Dipurena stranyulata AGASS. Cont. Nat. Hist. U. S., IV. p. 341. 1862. 

Charleston, S. C. (McCrady). 



Dipurena cervicata 

Dipurena cervicata McCR. Gymn. Charleston Harbor, p. 34. 
Dipurena cervicata AGASS. Cont. Nat. Hist. U. S. IV. p. 341. 1862. 

Charleston Harbor (McCrady). 



Dipurena conica A. AGASS. 

Dipurena conica A. AGASS. ; in Agassiz's Cont. Nat. Hist. U. S., IV. p. 341. 1862. 

In the young Medusa the shape of the bell is nearly sugar-loaf (Fig. 
301); the cavity of the bell is formed by a Fig . 301 . 

similar cone, with rounded apex ; the disk di- 
minishes rapidly in thickness towards the cir- 
cular tube ; the digestive cavity does not ex- 
tend quite to the level of the veil ; it is divided 
by a constriction into two unequal cavities, the 
upper one (it, Fig. 302) being about half the 
size of the lower one (I, Fig. 302) ; the walls of this cavity are thick, 
tapering gradually towards the actinostome, which is a simple opening, 
without labial appendages ; the digestive cavity is scarce- Fig 302 . 
ly contractile ; the four marginal tentacles are short, the 
sensitive bulb is large, consisting of minute granular cells, 
the eye-speck being placed in a small button, standing 
out slightly from the base of the tentacle on the upper 
side (the abactinal side). (Fig. 303.) The walls of the ten- 
tacles are thick ; they are made up of large elongated poly- 
gonal cells, giving the tentacles a striated appearance ; the 
tube running through the tentacles is exceedingly fine, 
expanding slightly towards the extremity, where it joins 
the cavity of the terminal club ; the large polygonal cells of the tenta- 
cle decrease in size towards the extremity, where there is a crescent- 
Fig. 301. Young Dipurena conica ; magnified. 
Fig. 302. Digestive cavity of a young Dipurena conica. u, the upper part ; /, the lower. 





182 



DIPURENA CONICA. 



Fig. 303. 





shaped row of large elliptical cells surrounding the upper end of the 

terminal cavity, these cells being sur- 
mounted by a thick coating of small 
granular cells, extending along the sur- 
face of the tentacle until they gradually 
disappear ; these granular cells are pig- 
ment-cells, giving the terminal club a 
reddish tinge ; the sensitive swelling at the base of the tentacles is 
colored by similar cells, the eye-spot being black. 

This species differs from the Dipurena strcmgulata in the form of 
the bell, the proportions of the digestive cavity and of the terminal 
clubs of the tentacles, as well as the shape of the sensi- rig . 301 . 

tive bulbs ; according to McCrady, they are exceedingly 
pointed in D. strangulata, while the sensitive bulb of D. 
cornea widens as it approaches the circular tube. The 
largest specimens taken were one sixth of an inch in 
diameter ; smaller specimens, not more than an eighth 
of an inch, differed greatly from the more advanced. 
The bell is almost globular, of uniform thickness ; the 
digestive cavity is short and rectangular in shape. As 
the young advance in age, the spherosome becomes more 
and more bell-shaped, and then conical ; as the digestive trunk increases 
in length, it contracts near the base, and becomes pear-shaped towards 
the extremity. When still quite young, the first appearance of the 
constriction becomes visible ; larger and older specimens, measuring 
one fourth of an inch, have a digestive cavity divided into two cavities, 

separated by a constriction, 
as in Fig. 304, where this 
separation has become quite 
prominent ; when the Medu- 
sa is in violent motion, the 
proboscis will assume a quad- 
rangular shape, with a large 
four-sided opening ; this flex- 
ibility of the actinostome is 
lost in older specimens. In 
the oldest specimens which 
have been found (Fig. 305), 
the separation between the 
upper and lower part of the digestive trunk has become such, that the 

Fig. 303. Tentacle of Dipurena conica. 

Fig. 304. Digestive cavity of a specimen in which the constriction has already separated the 
upper and lower halves. 

Fig. 305. Adult Dipurena conica, in which the two digestive cavities are widely separated ; 
greatly magnified. 




ORTHOCORYNIDJE. 183 

tAvo parts are simply connected by a narrow tube as long as the diges- 
tive cavities themselves ; the narrow tube leading to the first digestive 
cavity extends to the level of the veil ; the radiating tubes and the 
circular tube are thin, but there is no difference in the shape of the 
bell and of the tentacles of the different stages observed. 

Buzzard's Bay, Naushon (A. Agassiz). 

Cat. No. 439, Naushon, July, 1864, A. Agassiz. 

Museum Diagram, No. 20, after A. Agassiz. 



Family ORTHOOORYNID^E A. Agass. 

J have ventured to separate the genus Zanclea from the Pennaridce, 
with which it had been associated by McCrady and Professor Agassiz, 
and to form a new family, on account of the observations of Allman on 
the development of Zanclea from its Hydroid, Coryne impressa Aid. 
The peculiar form of the Hydrarium, and the still more remarkable 
characters of the Medusae, with their tentacles bearing pedunculated 
knobs of lasso-cells, separate them from the square Medusae of the 
Pennaridse, while they remind us somewhat of the embryonic stages 
of Syndictyon. From the resemblance of this Hydroid to Halocharis 
and to Candelabrum, as well as owing to the close affinities of Cory- 
nitis to Zanclea, I would propose to unite all these forms into one 
family, the Orthocorynidae. Does not also the Heterocordyle Cony- 
bearei belong to this family ? The great difference between the repro- 
ductive and the sterile individuals is another example of the polymor- 
phism so remarkable in Hydractinia. 

CORYNITIS McCE. 

Corynitis McCR. Gymn. Cliarl. Harbor, p. 29. Medusa. 

Corynitis AGASS. Cont. Nat. Hist. U. S., IV. p. 340. 1862. 

Halocharis AGASS. Cont. Nat. Hist. U. S., IV. p. 239. 1862. Hydrarium. 



Corynitis Agassizii McCR. 

Corynitis Agassizii McCR. Gymn. Cliarl. Harbor, p. 30, PI. 9, Figs. 3-8. 

Corynitis Agassizii AGASS. Cont. Nat. Hist. U. S., IV. p. 340. 1862. 

Halocharis spiralis AGASS. Cont. Nat. Hist. U. S., IV. p. 239, PI. 20, Figs. 10, 10. 1862. 

Charleston, S. C. (McCrady). 



184 



GEMMARIA. 



GEMMARIA McCR. 

Gemmaria McCR. Gymn. Charl. Harbor, p. 49. 
Zanclea McCR. (non Geg.). Gymn. Charl. Harbor, p. 48. 
Zanclea AGASS. (p. p.). Cont. Nat. Hist. U. S., IV. p. 344. 1862. 
Acrochordium MEY. ; in Nov. Ac. N. Aur XVI. 1834. Hydrariuin ? 



Gemmaria gemmosa 



Gemmaria gemmosa McCR. Gymn. Charl. Harbor, p. 49, PI. 8, Figs. 4, 5. 

Zanclea gemmosa McCR. Gymn. Charl. Harbor, p. 49. 

Zanclea gemmosa AGASS. Cont. Nat. Hist. U. S., IV. p. ^ ien ' 7 



Kg. 306. 



McCrady has distinguished with reason the genus Gemmaria from 

the Zanclea of Gegenbaur. The form 
of the bell of the digestive cavity and 
of the tentacles are totally different in 
the two genera. Very young specimens 
(Fig. 306) of this species, observed at 
Naushon, differed essentially from the 
Gemmaria cladophora of Massachusetts 
Bay, in the character of the tentacles 
and the shape of the clusters of lasso- 
cells ; in the present species, the clus- 
ters of lasso-cells are attached by a short 
peduncle, and are arrow-shaped ; the 
great tenuity of the bell in the speci- 
men here figured is a characteristic of the younger stages, which dis- 
appears in older specimens. (See McCrady 's figures.) . 
Charleston, S. C. (McCrady) ; Buzzard's Bay, Naushon (A. Agassiz). 




Gemmaria cladophora A. AGASS. 

The shape of the inner bell of the adult Medusa of this species is 
peculiar ; the outline does not follow that of the outer bell (Fig. 307), 



Fi". 307. 




Fig. 306. Profile view of half of a young Gemmaria gemmosa ; magnified. 
Fig. 307. Profile view of Gemmaria cladophora ; magnified. 




GEMMARIA CLADOPIIORA. 185 

but is curved in the opposite direction ; near the upper bend of the 
chymiferous tubes, it runs up into a point, making a sharp and deep 
groove round the projection of the rig. sos. 

spherosome ; the chymiferous tubes 
(Y, Fig. 308), as well as the circu- 
lar tube, are very broad (Fig. 308), 
opening into a conical digestive 
cavity, which at its base occupies 
nearly the whole width of the up- 
per part of the inner bell ; this cav- 
ity tapers gradually till it reaches 
the level of the veil, where the 
edges flare a little ; the extremity 
of the proboscis has a tendency to be slightly drawn in, so that the 
opening of the cavity is flanked by the pouches formed by the partial 
contraction of a portion of the w r alls ; the w r alls are thick, and open into 
Fi g. 309. a quadrangular mouth (Fig. 309), surrounded by a 

couple of concentric rows of large lasso-cells ; simi- 
lar large cells extend on the outside of the chymif- 
erous tubes, more than half-way up the sphero- 
some. (Fig. 308.) 

The tentacles are broad and thick, two of them 
being more developed than the others (Fig. 307) ; 
they are of a light-brown color, with orange pig- 
ment-cells at the base ; the knobs of lasso-cells are attached to quite 
long stems (Fig. 310) ; the walls of the digestive cavity are 
thick ; the ovaries are placed in the upper part of the proboscis. 
Found at Nahant in the beginning of August. When at rest, 
the tentacles are stretched out very obliquely from the bell, 
and they often remain perfectly motionless in this position ; 
the Medusae are quite rapid in their movements. (Fig. 307.) 

Professor Clark discovered at Nahant a Hydroid closely resembling 
the Coryne implzxa of Alder, and which I suspect will prove to be the 
nurse of our Gemmaria ; this would be in accordance with the observa- 
tions of Allman on the development of Zanclea from Coryne, implexa. 
Massachusetts Bay, Nahant (A. Agassiz). 
Cat. No. 363, Nahant, 1862, A. Agassiz. Medusa. 
? Cat. No. 63, Nahant, May, 1862, H. J. Clark. Hydrarium. 
Museum Diagram, No. 20, after A. Agassiz. 

Fig. 308. Quarter of the disk of G. cladophora, seen from the abactinal pole, c, circular 
tube ; c', chymiferous tube ; &, sensitive bulb, having a great accumulation of pigment and lasso 
cells extending along the chymiferous tubes ; c", opening leading into the chymiferous tubes from 
the digestive cavity, o ; g, g, genital organs ; </', fatty globules at base of proboscis. 

Fig. 309. Actinostome of Gemmaria, enlarged. 

Fig. 310. Cluster of lasso-cells of the marginal tentacles. 
NO. ii. 24 





186 PENNARIDJE. 



CANDELABRUM BLAINV. 

Candelabrum BLAINV. Man. d'Actin., p. 307. 1834. 
Candelabrum AGASS. Cont. Nat. Hist. U. S., IV. p. 340. 1862. 
Myrioihela SARS. Reise i Lof. og Fin., p. 14. 
Spadix GOSSE; in Ann. & Mag. N. II., p. 125. 1855. 



Candelabrum phrygium BLAINV. 

Candelabrum phryf/ium BLAIXV. Man. d'Actin., p. 317. 1834. 
Lucernaria phrygia FAB. Fauna Gronlandica. No. 333. 
Lucernaria phrygia AGASS. Cont. Nat. Hist. U. S., IV. p. 341. 1862. 
Corymorpha phrygia MORCII. ; in Besk. af Gronland, p. 96. 

Greenland (Fabricius) ; Grand Manan (W. Stimpson). 

Cat. No. 1G1, Grand Manan, "W. Stimpson. Hydromedusarium. 



Family PENNARID^E McCr. 

PennaridcB McCR. (restr. A. Agass.). Gymn. Charl. Harbor, p. 46. 
Pennaridce AGASS. (p.p.). Cont. Nat. Hist. U. S., IV. pp. 278, 344. 18G2. 

This family is restricted here to the single genus Pennaria, Zanclea 
having been removed from this family since the discovery of its devel- 
opment from a Coryne-like Hydrarium by Allman. 



PENNARIA GOLDF. 

Pennaria GOLDF. (non Oken). Handb. der Zoologie, p. 89. 1820. 
l'i in/firia McCu. Gymn. Charl. Harbor, p. 50. 

Pennaria AGASS. Cont. Nat. Hist. U. S., IV. pp. 278, 344. 1862. 
Globiceps AYRES ; in Proc. Bost. Soc. Nat. Hist., IV. p. 193. 1852. 
Globiceps AGASS. Cont. Nat. Hist. U. S., IV. p. 344. 1862. 
Eucoryne LEIDY. Inv. N. J. and R. I., p. 4. 1855. 

I have not given to the Globiceps tiareUa of Ayres a new generic 
name, although it is probable that it does not belong to the same 
genus as the Pennaria gibbosa Agass., as the development of the latter 
species requires renewed examination to decide the question. 



Pennaria gibbosa AGASS. 

Pennaria gibbosa AGASS. Cont. Nat. Hist. U. S., IV. pp. 278, 344 ; III. PL 15, Figs. 1, 2. 

Florida (L. Agassiz). 

Cat, No. 19, Key West, Florida, March, 1853, L. Agassiz. Hydrome- 
dusarium. 

Cat. No. 20, Jeremie, Hayti, Dr. Weinland. 



PENNARIA TIARELLA. 



187 




Pennaria tiarella McCR. 

Pennaria tiarella McCR. Gymn. Charleston Harbor, p. 51. 

Glolnccps tiarella AYRES ; in Proe. Bost. Soc. Nat. Hist,, p. 103, PL X. Figs. 1-5. 1852. 

Eucoryne elegans LEIDY. Mar. Inv. N. J. and R. I., p. 4. 1855. 

Globiceps tiarella AGASS. Cont. Nat. Hist. U. S., IV. p. 344. 1862. 

The Medusa of GloUceps tiarella is Fig ' 311 ' 

one of the most remarkable of our 

naked-eyed Medusae. As in the Sarsi- 

adae, the Medusa bud is formed among 

the tentacles (Fig. 311), between the 

whirl of large and small tentacles ; the 

mode of development of the bud is 

similar to that of Coryiie and Bou- 

gainvillia ; the chymiferous tubes, how- 
ever, never have the extraordinary 

thickness which is noticed in Sarsia, 

and the cavity of the bell is hollowed 

out at an earlier period ; the Medusa bud gradually becomes very elon- 
gated as it becomes more mature. 

Large white eggs are developed from the pro- 
boscis, filling the whole cavity of the bell as 
they increase in size, and giving the Medusa an 
opaque milky appearance ; the walls of the 
spherosome become thinner and thinner, and 
when the Medusa bud has attained its full de- 
velopment, and is ready to be separated, the 

walls have become so thin that the Medusae 

are almost always distorted, either on one side 

or the other, by the eggs or bunches of sper- 

maries which have reached such a great size 

that four or five of them completely fill the 

inner cavity, at the same time pressing the 

sides outward, wherever one of the large eggs 

happens to be placed (e, Fig. 312) ; two or 

three of the eggs generally escape before the 

Medusa bud is liberated, and when they are 

found detached, the cavity of the bells usually 

does not contain more than one or two large 

eggs ; folds appear on the inner surface of the 

cavity of the bell after the eggs have escaped, 

Fig. 311. A fertile Hydra of Pennaria tiarella, showing the mode of budding ; magnified. 
Fig. 312. A Medusa distended by an egg, e ; magnified. 

Fig. 313. Profile view of Medusa of Pennaria tiarella; magnified, f, folds produced by the 
distension of spherosome. 




Fig. 313. 




188 PENNARIA TIARELLA. 

owing to their distension (f, Fig. 313) ; as soon as the eggs have all 
escaped, and the Medusie have become detached, they move about with 
great activity, their motions resembling the quick, restless movements 
of Sarsia. 

The size of the free Medusa is about one sixteenth of an inch ; the 
walls of the spherosome are so thin that the Medusa will often assume 
a quadrangular or octagonal outline (Fig. 314), with deep indentations 
between the chymiferous tubes (Fig. 315) ; the digestive trunk is short, 
bottle-shaped, not extending more than half the length of the inner 
cavity of the bell ; it is suspended by the narrow part (Fig. 313), the 
connection of the digestive cavity with the Hydrarium dividing the 
abactinal part of the bell in such a way that when seen in profile there 
are two circular masses above the chymiferous tubes. As the Medusa 
grows older, this open connection does not seem to diminish, as it does 
in the Sarsiadse, Bougainvilleae, and others. The chymiferous tubes, 

Fig. 314. Fig. 315. 





four in number, are broad, running almost perpendicularly, after mak- 
ing a sharp bend at the top, from the abactinal pole to the circular 
tube ; there are also four well-developed sensitive bulbs ; the tentacles 
on the contrary remain always in a rudimentary condition (Fig. 313), 
being simply four small knobs scarcely projecting beyond the general 
outline of the bell ; the opening of the veil is small. 

What becomes of the Medusa after the eggs have escaped, I am not 
able to say, though I am inclined to think that they do not undergo 
changes of any importance, as I have kept them in confinement for 
three weeks without noticing any striking differences. The color of 
the Medusa, when freed from its eggs, is of the most delicate rose color; 
the digestive trunk and the chymiferous tubes are a little darker, and a 
line of rich crimson pigment^cells, running almost their whole length, 
makes this Medusa one of the most brilliantly colored of our coast. 
Found at Naushon, during the month of September. 

Buzzard's Bay (Ayres, A. Agassiz) ; Massachusetts Bay (A. Agassiz) ; 
New Jersey (Leidy) ; Charleston, S. C. (McCrady). 

Fig. 314. A different attitude of the Medusa, seen from the actinal pole. 
Fig. 315. Fig. 313, seen from the abaetinal pole. 



TUBULARIADCE. 189 

Cat. No. 21, Suisconset, Mass., July, 1849, L. Agassiz. Hydromedu- 
sarium. 

Cat. No. 22, NaiTshon, Sept, 1861, A. Agassiz. Hydromedusarium. 

Cat. No. 23, Newport, R. L, Prof. J. Leidy. Hydromedusarium. 

Cat. No. 24, Newport, R. L, S. Powell. Hydromedusarium. 

Cat. No. 25, Beverly, Mass., T. Lyman. Hydrarium. 

Cat. No. 26, West Yarmouth, Mass., Aug. 1860, T. Lyman. Hydrarium. 

Cat. No. 407, Nahant, September, 1862, A. Agassiz. Hydrarium. 



Family TUBULARIAD^E Johnst. 

Tubulariadce JOHXST. (restr. Agass.) ; in Trans. Berwick Club, p. 107. 
Tubulariadce AGASS. Cout. Nat. Hist. U. S., IV. p. 342. 1862. 



EUPHYSA FORBES. 

Euphysa FORBES. British Naked-eyed Medusae, p. 71. 1848. 
Euphysa AGASS. Cont. Nat. Hist. U. S., IV. p. 343. 1862. 

The outline of the bell of this genus is entirely different from that 
of Corymorpha or of Hybocodon. It can at once be recognized by its 
quadrangular shape, and the great thickness of the spherosome above 
the base of the digestive cavity, which is short and cylindrical. The 
tentacles also are always short and hollow, but are developed in the 
same proportion as in Corymorpha, one stout triangular one, a pair 
somewhat less advanced, and an odd rudimentary one ; the large tenta- 
cle never attains the size which it does in Hybocodon or in Corymorpha. 
The pigment bands at the base of the tentacles are quite short, and 
extend but little way along the chymiferous tubes. The ovaries are 
placed on the sides of the proboscis ; the bell is symmetrical. 



Euphysa virgulata A. AGASS. 

This Medusa attains a size of about half an inch ; the polar diameter 
is nearly one third greater than the actinal (Fig. 316) ; the proboscis 
(Fig. 317) is short, not more than half the length of the inner bell (Fig. 
316) ; the veil is slightly indented (Fig. 318) ; the tentacles (t, t', 
Fig. 318) are triangular, and covered with large granules of a milky 
color, with a band of intensely pink pigment-cells extending a short 
distance (p. Fig. 319) along the chymiferous tubes, from the base of 
the tentacles ; the proboscis is cylindrical, of a light yellow color, with 
a perfectly smooth actinostome, and fatty globules generally accumu- 
lated at the base (<?, Fig. 317), as in Corymorpha and Hybocodon. 



190 



ECTOPLEURA. 



The Medusa is exceedingly active, moving very rapidly and inces- 
santly. Found at Nahant in the latter part of August. 

Fig. 319. 



Fig. 316. 




Fig. 317. 





Euphysa is not, as Professor Agassiz has stated, the generation of 
Medusae which become separated from the base of the reproducing 
tentacle in Hybocodon. That generation of Medusae are identical with 
the parent Medusa, as well as the second generation which bud from 
the large tentacle of this first set of Medusae. 

Massachusetts Bay, Nahant (A. Agassiz). 

Cat. No. 452, Nahant, A. Agassiz. 



ECTOPLEURA AGASS. 

Ectopleura AGASS. Cont. Nat. Hist. U. S., IV. p. 342. 1862. 

In this genus I would include those species of the genus Sarsia (like 
Oceania telostyla Geg., Sarsia turricula McCrady, and Sarsia gemmi- 
fera Forbes) which have a short digestive trunk, and in which the 
pigment-cells are not concentrated in one mass in the sensitive bulb, 
but are scattered irregularly through the whole swelling at the base of 
the tentacles. 

Fig. 316. Euphysa virgulata, seen in profile ; magnified. 

Fig. 317. Proboscis of Euphysa. , actinostome ; , ovaries ; </, fatty globules ; magnified. 

Fig. 318. Actinal view of Euphysa, to show the character of the veil, t, the odd long tenta- 
cle ; t', one of the pair of tentacles ; *", the odd small tentacle. 

Fig. 319. One of the tentacles seen in profile, to show the character of the band of pigment 
cells,/), extending along the base of the chymiferous tube from the origin of the tentacle, t'. 



ECTOPLEURA OCHRACEA. 191 



Ectopleura turricula AGASS. 

Ectopleura turricula AGASS. Cont. Nat. Hist. U. S., IV. p. 343. 1862. 
Sarsla turricula McCu. Gymn. Charleston Harbor, p. 36, PL 8, Figs. 6-8. 

Charleston, S. C. (McCrady). 



Ectopleura ochracea A. AGASS. 

Ectopleura ochracea A. AGASS. ; in Agassiz's Cont. Nat. Hist. U. S., IV. p. 343. 1862. 

The bell is of uniform thickness from the circular tube as far as the 
base of the digestive cavity ; here the outline tapers gradually towards 
the abactinal pole (Fig. 320), giving Fig. 320. 

the upper part of the bell a much 
greater thickness, and a conical shape. 
Near the base of the digestive cavity 
there is a very marked constriction ; 
it then bulges out towards the middle, 
contracting again towards the actinos- 
toine, which is simple ; the opening is 
formed by the abrupt termination of 
the walls of the digestive cavity ; there 
are no labial appendages of any sort, 
except small bunches of lasso-cells. The 
tentacles are short ; when swimming 
about they are usually carried tightly 
curled up near the circular tube. This 
species differs from the S. turricula McCr. in having the surface of the 
tentacles covered irregularly with innumerable lasso-cells ; they are not 
arranged in bundles, as in the Charleston species. From each side of 
the base of the four tentacles there runs to the abactinal pole (Figs. 
321, 322) a thread of bunches of lasso-cells (I, Fig. 320), like that of 
Turritopsis. The bunches are large near the actinal extremity, and 
gradually diminish to the abactinal pole, where there is only one cell, 
while near the base of the tentacles the bundles are made up of aggre- 
gations of clusters of lasso-cells, consisting of two or three cells each. 
An accumulation of bright yellow pigment-cells forms a ring round the 
point of attachment of the digestive trunk ; the digestive cavity itself 
is of a delicate rose color, with whitish bunches of lasso-cells at the 
actinostome, surmounted by a second light yellow ring immediately 
above it ; the tentacles are of the color of the digestive trunk, but of a 

Fig. 320. Profile of Ectopleura ochracea, magnified. /, thread of lasso-cells extending to ab- 
actinal pole ; p, pigment-cells at base of tentacles. 




192 CORYMORPHA. 

lighter tint ; the pigment-cells in the sensitive bulb (p, Figs. 320, 323) 
are purplish-orange upon a light-yellow ground. When the Medusae 

I'ig- 321. Fig. 322 






move about, which they do with great rapidity, the tentacles are twisted 
in knots, as stated above, but when at rest expand at right angles to 
Fig. 323. the disk, and then the Medusa will often remain, bal- 

ancing itself upon its tentacles, perfectly motionless in 
the water, appearing like a rosy tube, with its yellow 
ring set in a rectangle of four brilliantly colored ocelli. 

Found at Naushon in September, the largest speci- 
men being one fourth of an inch in diameter ; young 
specimens have a shorter digestive trunk, and the rows 
of lasso-cells extending along the outer surface of the 
bell are more marked than in older specimens. The 
Hydroid of this Medusa probably resembles the Tubular ia Dumortierii 
Van Beneden, the Medusa of which is closely allied to the one found 
on our coast. 

Buzzard's Bay, Naushon (A. Agassiz). 

Cat. No. 441, Naushon, Mass., A. Agassiz. Medusa. 



CORYMORPHA SARS. 

Corymorpha SARS. Beskriv., p. 6. 1835. 

Corymorpha AGASS. Cont. Nat. Hist. U. S., IV. p. 343. 1862. 



Corymorpha pendula AGASS. 

Cori/morpfta pendula AGASS. Cont. Nat. Hist. U. S., IV. pp. 276, 343, PI. 26, Figs. 7-17. 

Corymorpha nutans STIMPS. Mar. Inv. Grand Manan, p. 9. 1853. 

Corymorpha pendula A. AGASS.; in Proc. Bost. Soc. Nat. Hist., IX. p. 101, Fig. 31. 

The Medusa of Corymorpha is, like Hybocodon, asymmetrical ; the 
shape of the bell is more elongated (Fig. 324) and the tentacles more 

Fig. 321. Fig. 320, seen from abactinal pole, to show the termination of the lasso threads. 
Fig. 322. Fig. 320, seen from the actinal pole, showing the origin of the threads on each side 
of the base of the tentacles. 

Fig. 323. The base of one of the tentacles, magnified, p, cluster of pigment-cells. 



HYBOCODON. 



193 



Fig. 32i. 



developed, the long tentacle (Fig. 324) .attaining a size two or three 
times the length of the hell ; the proboscis is long, and stretches be- 
yond the aperture of the veil; the long tentacles (1, 2, Fig. 324) are 
capable of great contraction and expansion ; the lasso- 
cells are arranged in groups upon them in such a manner 
as to appear like heavy rings surrounding the thinner 
thread , the outer wall of the proboscis is exceedingly 
thick, as in the Medusa of Euphysa, and of a light-yellow 
color ; the pigment-cells at the base of the tentacles are 
light pink. This Medusa attains a size of a quarter of an 
inch, and is found at Nahant in the middle of May. 

Although the separation of this Medusa from its Hy- 
drarium has not been observed, yet their similarity to the 
most advanced Medusa? buds observed on our Corymor- 
pha leave but little doubt on this point. Hodge has 
observed the development of an English species of Corymorpha, which 
resembles the Medusa here figured. (Fig. 324.) 

Massachusetts Bay, Nahant (L. Agassiz). 

Cat. No. 18, off Race Point, Cape Cod, Mass., March, 1862, A. S. Bick- 
more. Hydromedusarium. 

Museum Diagram, No. 24, after L. Agassiz. 




HYBOCODON AGASS. 

Hi/bocodon AGASS. Cont. Nat, Hist. U. S., IV. p. 343. 1862. 



Hybocodon prolifer AGASS. 

Hybocodon prolifer AGASS. Cont. Nat. Hist. U. S., IV. pp. 243, 343, PI. 23\ Figs. 10, 11 ; PI. 25. 

18G2. 

This is one of the few known Tubularians 
found growing singly. (Fig. 325.) The char- 
acter of the Medusas is particularly important 
in a morphological point of view, giving us, as 
it does, the clew to the probable character of 
the scales (Deckstiick) of the Nanomia, de- 
scribed below. The asymmetrical character of 
the Medusa (Figs. 326, 327) is more marked 
than in the Medusa of Corymorpha, The bud- 
ding of Medusas (Fig. 328), similar to the parent 

Fig. 324. Medusa of Corymorpha, seen in profile. 1, long odd tentacle ; 2, pair of tentacles , 
3, short odd tentacle. 

Fig. 325. Single Hydra of Hybocodon. o, mouth surrounded with tentacles ; t, /, marginal 
tentacles ; d, d, advanced Medusae buds ; o, stem. 

NO. II. 25 




194 



PARYPHA. 



Medusa, from the base of the single largely-developed tentacle, is a 
feature it has in common with other Medusas which have been referred 
by various writers to the genera Sarsia and Steenstrupia, and which 
very probably are all derived from a Tubularian nurse similar to Hy- 



Fig. 326. 






bocodon. Should the Diplonema of Greene prove to be one of these 
asymmetrical Medusae, the name Hybocodon must give way to that of 
Diplonema. 

Massachusetts Bay (L. Agassiz). 

Cat. No. 61, Nahant, Mass., May, 1862, H. J. Clark. Hydrarium. 

Museum Diagram, No. 23, after L. Agassiz. 



PARYPHA AGASS. 

Parypha AGASS. Cont. Nat. Hist. U. S., IV. p. 342. 18G2. 
Pyxidium LEUCK. ; in Archiv f. Nat, I. p. 31. 1856. 



Parypha cristata AGASS. 

ParypJta cristata AGASS. Cont. Nat. Hist. U. S., IV. p. 342. 1862. 
Tubularia cristata McCn. Gyinn. Charleston Harbor, p. 54. 

Charleston, S. C. (McCrady). 

Cat. No. 14, Sullivan's Islands, S. C., December, 1851, L. Agassiz. 

? Cat. No. 16, Florida, 1850, L. Agassiz. 

Fig. 326. Hybocodon prolifer Agass., seen from the broad side, v, proboscis; r, o, radiating 
tubes ; s, circular tube ; m, buds of Medusa; at base of long tentacle, t. 

Fig. 327. Hybocodon prolifer, seen facing the long tentacle, n, point of attachment to Hy- 
drarium ; b, c, radiating tubes ; e, rows of lasso-cells extending from base of tentacle to abactinal 
pole ; o, proboscis ; /, Medusas budding from base of long tentacle, t. 

Fig. 328. Medusa bud of Hybocodon. a, base of attachment ; o, proboscis; &, c, chymiferous 
tubes ; d aud near c, Medusas buds at base of tentacle, t. 



THAMNOCNIDIA. 195 

Parypha crocea AGASS. 

Paryplia crocea AGASS. Cont. Nat. Hist. U. S., IV. pp. 249, 342, Pis. 23, 23% Figs. 1-7. 1862. 

Boston Bay (L. Agassiz). 

Cat. No. 13, Warren Bridge, Boston, June, 1858, II. J. Clark. Hy- 
clromedusarium. 

Parypha microcephala A. AGASS. 

Kesembles in its general aspect the Parypha cristata Agass. ; the 
stem is more slender than that of P. crocea., found in Boston Harbor ; 
the head is much smaller than in either of the above-mentioned spe- 
cies, though the stem grows to a size fully as great as in our Eastern 
Parypha, giving it a very characteristic aspect. Found attached to 
floating logs round the wharves of San Francisco. 

San Francisco, Cal. (A. Agassiz). 

Cat. No. 15, San Francisco, Cal., October, 1859, A. Agassiz. Hydro- 
medusarium. 

Cat. No. 17, San Francisco, Cal., December, 1859, A. Agassiz. Hydro- 
medusarium. 

THAMNOCNIDIA AGASS. 

Thamnocnidia AGASS. Cont. Nat. Hist. U. S., IV p. 342. 1862. 

Thamnocnidia spectabilis AGASS. 

Thamnocnidia spectabilis AGASS. Cont. Nat. Hist. U. S., IV. pp. 271, 342, PI. 22, Figs. I - 20. 18G2. 

Massachusetts Bay, Boston (L. Agassiz). 

Cat. No. 6, Boston, August, 1851, H. J. Clark. Hydromedusariuni. 



Thamnocnidia tenella AGASS. 

Thamnocnidia tenella AGASS. Cont. Nat. Hist. U. S., IV. pp. 275, 342, PI. 22, Figs. 21 - 30. 1862. 

Massachusetts Bay, Nahant (L. Agassiz). 

Cat. No. 7, Nahant, Mass., September, 1854, H. J. Clark. Hydrome- 
dusarium. 

Cat. No. 8, Nahant, July, 1861, A. Agassiz. Hydromedusarium. 
Cat. No. 410, Eastport, Me., 18G1, Anticosti Expedition. 
Cat. No. 411, Eastport, Me., 1863, A. E. Verrill. 
Cat. No. 412, Eastport, Me., 1863, A. E. Verrill. 



196 TUBULARIA. 

Thamnocnidia tubularoides A. AGASS. 

This species grows in clusters, which at first sight would readily be 
mistaken for a species of true Tubularia, on account of the great diam- 
eter of the stem, and the large size of the head. The structure of the 
proboscis, however, shows plainly that it is a genuine Thamnocnidia, 
which can at once be distinguished from its Eastern congeners by the 
stoutness of the stem and size of the head, surrounded by as many as 
from thirty and even forty tentacles in large specimens. Found grow- 
ing profusely on the bottom of the coal-barges which bring coal from 
Benicia to the Pacific Mail Steamship Company's steamers at San 
Francisco. 

San Francisco, Cal. (A. Agassiz). 

Cat. No. 11, San Francisco, Cal., December, 1859, A. Agassiz. Hy- 
dromedusarium. 



TUBULARIA LINN. 

Tubularia LINN, (restr. Agass.). Syst. Nat. 1756. 
Tubularia AGASS. Cont. Nat. Hist. U. S., IV. p. 342. 1862. 



Tubularia larynx LINN. 

Tubularia larynx ELLIS. Cor., PL 16, Fig. 6. 

Tubularia larynx JOIINST. Brit. Zooph., p. 50, PI. 3, Fig. 3 ; PI. 5, Figs. 3, 4. 

Tubularia larynx STIMPS. Mar. Inv. Grand Manan, p. 9. 1853. 

Grand Manan (W. Stimpson). 



Tubularia Couthouyl AGASS. 

Tubularia Couthouyi AGASS. Cont. Nat. Hist. U. S., IV. pp. 266, 342, PI. 23", Figs. 8, 9 ; Pis. 

24, 26, Figs. 1-6. 1862. 

Tubularia indivisa STIMPS. Mar. Inv. Grand Manan, p. 9. 1853. 
Tubularia indivisa GOULD. Rep. Inv. Mass., p. 350. 1841. 
Tubularia indivisa MORCH ; in Besk. af Gronland, p. 96. 1857. 

Massachusetts Bay (L. Agassiz). 

Cat. No. 4, Boston, August, 1851, H. J. Clark. Hydromedusarium. 
Cat. No. 5, Grand Manan, 1857, J. E. Mills. Hydromedusarium. 
Museum Diagram, No. 24, after L. Agassiz. 



HYDRAID^E. 197 



Family HYDRAID^ Gray. 

Hydraidce GRAY. Syn. Brit. Mus., p. 76. 1840. 
Ifydrina EHRENB. (p. p.). Corall. d. Roth. Meercs, p. 67. 
Hydraidce JoiiNST. Brit. Zooph., p. 120, Second Edition. 



HYDRA LINN. 

Hydra LINN. Syst. Nat. 1 756. 

Hydra gracilis AGASS. 

Hydra gracilis AGASS. ; in Proc. Bost. Soc. Nat. Hist., III. p. 354. 
Hydra gracilis AYRES ; in Proc. Bost. Soc. Nat. Hist., V. p. 103. 

Our fresh-water Hydra has as yet been studied so insufficiently, 
that I am unable to add anything respecting the development of the 
Medusae, or concerning its identity with the European Hydra viridis. 
Agassiz has described two Eastern species under the name of Hydra 
gracilis and H. carnea, and Ayres a California species. From the 
character of the Medusae of the Hydra, it seems to me that it finds 
its natural place among the true Hydroids, and not among the Dis- 
cophorne, with which it has usually been associated, on account of its 
close resemblance to the Scyphistoma (Hydra tuba}. 

Cambridge (L. Agassiz). 

Cat. No. 370, Cambridge, 1862, W. Glen. 

Hydra carnea AGASS. 

Hydra carnea AGASS. ; in Proc. Bost. Soc. Nat. Hist., HI. p. 354. 
Hydra carnea AYRES ; in Proc. Bost. Soc. Nat. Hist., V. p. 104. 

Massachusetts and Connecticut (Agassiz ; Ayres). 



Hydra tennis AYRES. 

Hydra tennis AYRES ; in Proc. Bost. Soc. Nat. Hist., V. p. 104. 

San Francisco, California (Ayres). 



198 



HYDE ACTINIAE. 



Family HYDRACTINIDCE Agass. 

Hydractinidce AGASS. Cont. Nat. Hist. U. S., IV. p. 339. 1862. 

HYDRACTINIA VAN BENEDEN. 

Hydractinia VAN BEXEDEN ; in Bull. Acad. Bel., VIII. 1841. 
Hydractinia AGASS. Cont. Nat. Hist. U. S., IV. p. 339. 1862. 
Synhydra QUAT. ; in Ann. des Scien. Nat., XX. p. 230. 1843. 



Hydractinia polyclina AGASS. 

Hydractinia polyclina AGASS. Cont. Nat. Hist. U. S., HI. PL 16 ; IV. pp. 227-239, 339, Figs. 

33-35; PL 26, Fig. 18. 1862. 

Hydra squamata FAB. Fauna Grb'nlandica. No. 338. 
Alcyonium echinatum GOULD. Rep. Inv. Mass., p. 351. 

Hydractinia echinata LEIDY. Mar. Inv. New Jersey and Rhode Island, p. 3, PL X. Fig. 35. 1855- 
Hydractinia echinata STIMPS. Mar. Inv. Grand Manan, p. 11. 1853. 
Hydractinia echinata McCn. Gymn. Charleston Harbor, p. 66. 
Clava squamata MORCH ; in Beskriv. af Grbnland, p. 96. 
Hydractinia polyclina PACK.; in Can. Nat. & Geol. Dec. 1863. 

As such constant reference is made to Hydractinia in the comparison 
of the free colonies of Nanomia to the fixed Hydroids, figures of male 

Fig. 330. 





(Fig. 329) and female (Fig. 330) colonies of this species are here intro- 
duced to facilitate the comparison. 

Point Judith (Leidy) ; Atlantic coast of North America (L. Agassiz). 

Cat. No. 55, Grand Manan, 1859, A. E. Verrill. 

Cat No. 56, Grand Manan, October, 1857, J. E. Mills. 

Cat. No. 57, Chelsea Beach, L. Agassiz. 

Cat. No. 58, Swampscott, Mass., March, 1859, S. Tufts. 

Cat. No. 59, Nantucket Shoals, July, 1849, L. Agassiz. 

Cat. No. 403, Nahant, Mass., July, 1862, A. Agassiz. 

Museum Diagram, No. 25, after L. Agassiz. 

Fig. 329. Part of male community of Hydractinia. , a, sterile individuals ; &, fertile indi- 
vidual ; f/, male Medusa? ; o, o, proboscis ; /, elongated tentacle of sterile individuals. 

Fig. 330. Part of female community, a, sterile individual ; 6, fertile individual, producing 
female Medusae, d, e, /, g, h, i ; o, peduncle of mouth ; c, individual with globular tentacles. 



DIPHY^E. 199 



SUBORDER DIPHY.E Cuv. 

Diphycc Cuv. Regne Animal, IV. 1817. 

Calycophoridce LEUCK. (/>/>) ; in Archiv f. Nat., I. p. 256. 1854. 

Dipliyce AGASS. Cont. Nat. Hist. U. S., IV. p. 370. 1862. 

For the reasons which have led me to adopt the old divisions of 
Eschscholtz, and not the divisions of Leuckart, which have found such 
universal approval, I would refer to the description of Nanomia given 
below. 



Family DIPHYID^l Esch. 

DipJu/idce ESCH. (restr. Agass.). Syst. der Acal., p. 122. 1829. 
Diphyidce AGASS. Cont. Nat. Hist. U. S., IV. p. 371. 1862. 



EUDOXIA ESCH. 

Eudoxia ESCH. Syst. dcr Acal., p. 125. 1829. 
Eudoxia LESS. Zooph. Acal., p. 460. 1843. 



Eudoxia alata McCu. 

Eudoxia alata McCR. Gymnoph. Charleston Harbor, p. 70, PI. 8, Figs. 9, 10. 

Charleston Harbor (McCrady). 

DIPHYES Cuv. 

Dlphyes Cuv. Regne Animal, IV. 1817. 
Erscea ESCH. Syst. der Acal., p. 127. 1829. 
Cucullus Q. & G. ; in Ann. des Sc. Nat., X. 1829. 
Diphyes LESS. Zooph. Acal., p. 438. 1843. 

Diphyes pusilla McCR. 

Dlphyes pusilla McCR. Gymn. Charleston Harbor, p. 72. 

Charleston, S. C. (McCrady). 



200 PHYSOPHOR^E. 



SUBORDER PHYSOPHORJE GOLDF. 

PJiysophorce GOLDF. Handb. d. Zool. 1820. 

Plnjsophorce AGASS. Cont. Nat. Hist. U. S., IV. p. 367. 1862. 



Family AGALMID^E Brandt. 

Agalmulce BRANDT ; in Mem. Acad. St. Petersburg, p. 234. 1838. 
Agalmce. LESS. Zooph. Acal., p. 509. 1843. 
Stephanomice LESS. Zooph. Acal., p. 475. 1843. 
Stcphanomidce LEUCK. ; in Archiv f. Nat., I. p. 312. 1854. 
Stephanomidce HUXL. Ocean. Hyd., p. 72. 1858. 
Agalmidce AGASS. Cont. Nat. Hist. U. S., IV. p. 368. 1862. 



NANOMIA A. AGASS. 

Nanomia A. AGASS. ; in Proc. Boston Soc. Nat. Hist., IX. p. 181. 1863. 

Nanomia cara A. AGASS. 

Nanomia cara A. AGASS. ; in Proc. Bost. Soc. Nat. Hist., IX. p. 181. 1863. 

This Siphonophore is closely allied to the genus Agalmopsis of Sars, 
but the nature of the tentacles of the feeding polyps, and the mode of 
arrangement of the swimming-bells, show undoubtedly that it cannot 
be placed in the same genus as Agalmopsis, though closely related to 
it, as also to Halistemma of Huxley. The small size of this species has 
been of great advantage, in enabling us to seize readily, at one glance, 
the connection between the different parts of this community, while 
the great size of many of the species hitherto observed has always been 
more or less of a drawback in analyzing the relations of the individuals 
of the community. 

Fi S . 331. The float, or swimming-bladder, (I shall use at present 

the nomenclature usually adopted, and afterwards show to 
what parts these organs correspond in an ordinary Hy- 
droid,) is a large elliptical cavity (Fig. 331), entirely shut 
off from the main cavity, which runs from the base of the 
float, through the whole of the axis of the community. It 
contains in this genus a bubble of oily substance ; the na- 
ture of the contents of the float varies in different families 
of Siphonophora?, and this cavity may or may not be closed. In this 
genus it is closed, and there is no access to the oil-bubble from with- 
out ; the oil-bubble by no means fills the whole of the cavity of the 
float. The float is of a brilliant garnet color ; from it hangs the rosy- 
Fig. 331. Oil-float of Nanomia ; magnified. 




NANOMIA CARA. 



201 



colored axis, with its pale swimming-bells, and farther down, the scales, 
protecting the different kinds of feeding polyps, with their various 
kinds of tentacles projecting in all sorts of angles and curves from the 
main axis of the body, like the festoons of a chandelier ; the darker- 
colored polyps, tipped and mottled with scarlet, being visible under- 
neath the protecting scales. (Fig. 332.) 

The swimming-bells are arranged in two vertical rows, consisting of 
four to six large bells each ; they are placed obliquely, in such a way 



Fig. 332. 




that the wing-like projections of the spherosome encroach upon those 
of the opposite row, and thus fit closely and compactly together, by a 
sort of oblique dovetail arrangement ; these bells are only symmet- 
rical when seen from one of the sides (Fig. 333), when they appear 
somewhat heart-shaped, having a large cavity which opens externally 
by means of an aperture (see Fig. 334) in a veil, similar to that of 
genuine naked-eyed Medusae, and capable, like it, of beating up and 



Fig. 332. Nanoraia cara ; natural size. 



NO. II. 



26 



202 



NANOMIA CARA. 



Tig. 333. 



down, and forcing the water in or out of the cavity of the bell. From 
the abactinal pole of this cavity diverge four chymiferous tubes, which 
lead into a circular tube, connecting them all (c, Fig. 334) ; two of these 
tubes, t', t', are straight, and run directly from the point of junction of 

the four tubes (j, Fig. 334) to the circular tube, 
while the other tubes, /, t, wind round before 
joining the circular tube. The connection of 
these chymiferous tubes with the tube into 
which they run, and which connects them all 
with the main cavity of the axis of the commu- 
nity, can readily be traced by combining the 
different views of the swimming-bell here given. 
(Figs. 333-336.) In Fig. 333 the straight chy- 
miferous tubes run perpendicularly to the circular tube, in continuation 
of the tube passing through the abactinal pole of the spherosome ; 
while in Fig. 336, which is a view at right angles to that of Fig. 333, 
we see the connection of the winding tubes with the connecting tube ; 
the opening (/, Fig. 335) of the connecting tube (t", Fig. 335) is some- 
what to one side of the point of junction of the chymiferous tubes 





Fig. 335. 
t' t" 




(j, Fig. 334), as is readily seen on examining Figs. 335, 336. Fig. 336 
shows the wing-like expansions of the spherosome which clasp the axis, 
giving the Medusa a conical appearance, when seen from that side ; 
while when seen from the actinal or abactinal pole, as Figs. 334, 335, 

Fig. 333. Swimming bell of Nanomia, seen facing the side of the straight chymiferous tubes. 

Fig. 334. The same bell, seen from the actinal pole, somewhat more magnified, t, t, bent chy- 
miferous tubes ; t', t', straight chymiferous tubes ; e, circular tube round veil ; j, point of junction 
of the four chymiferous tubes. 

Fig. 335. A portion of the same bell, seen from the abactinal pole ; lettering as in Fig. 334. 
j', opening of tube, t", leading into the main axis connecting with one of the straight chymiferous 
tubes. 



NANOMIA CARA. 



203 



Fig. 336. 




the shape cf the swimming-bell is rectangular. There can be but little 
doubt that these swimming-bells, as I have called them, are genuine 
Medusa) ; they have all the characters of Medusa), and when they be- 
come detached, move like them, the only difference being the absence 
of a proboscis to admit food. This, however, they do not need as long 
as they remain connected with the main axis, 
the cavity of which opens directly into the 
chymiferous tubes, and thus circulates in 
them whatever food is taken in at the feed- 
ing mouths, and from them passed into the 
cavity of the main axis. I have not been 
able to detect any opening leading directly 
into the system of chymiferous tubes. These 
Medusa? are the locomotive organs of the 
community ; they force the water in and out 
of their cavity, and thus propel the w r hole community by a sort of 
alternating motion, resembling that of sculling a boat ; the bells on one 
side of 'the axis are filling with water, while those of the other side are 
forcing the water out violently ; the motion begins at the bottom bell, 
passes on to the top one of the same side, then begins at the bottom of 
the other row, and so on, throwing the whole of the upper part of the 
community violently from one side to the other, while the remainder 
is dragging lazily after it. I have not found any specimens with more 
than eight swimming-bells fully developed ; the younger bells are 
added between the first-formed pair and the float, where we find a 
cluster of swimming bells in different stages of development. These 
young bells are formed, as the Medusa? buds of the Tubularians, by 
folds of the outer wall, which gradually grow larger and larger, and 
circumscribe parts of the main cavity to form chymiferous tubes. 

In their younger stages, the swim- 
ming-bells resemble still more the 
Medusa) of Hydroids, when they 
have not yet assumed an irregular 
outline, and while their chymiferous 
tubes are still straight. In the cluster 
of young bells here given (Fig. 337), 
we find a few of the different stages 
through w T hich one of these bells 
passes, from the time it appears as 
a mere bud, till it has gone through 

Fig. 33G. The same bell as Fig. 333, seen from the other side, to show the course of the bent 
tubes, and the mode of connection of the tubes leading into the main axis ; I, bent tube. 

Fig. 337. Group of swimming bells, in different stages of development, o, the chymiferous 
tubes are simple sacs ; ?>, the tubes, having united, make a circuit ; c, first signs of bending of the 
tubes, t, of the preceding figures. 



Fig. 337. 




204 NANOMIA CARA. 

the different phases in which the chymiferous tubes are mere pouches 
(a, Fig. 337), then large tubes connected by a circular tube (6, Fig. 337), 
till finally the bell becomes somewhat expanded at one pole, and the 
tubes have a tendency to bend, as in c, Fig. 337, when the difference 
between the two kinds of chymiferous tubes is quite marked, although 
the mode of attachment of the Medusa and the shape of the bell remind 
us strongly of Tubularian Medusae buds, and we find no trace as yet of 
the wing-shaped appendages, and of the difference of outline of older 
Medusae, when seen from different sides. 

As there is a portion of the axis, immediately beneath the float, 
which is free from swimming-bells, we find also under the swimming- 
bells a small part of the axis bare ; we soon, however, come upon a 
cluster of small buds entirely different in character from those found 
F ig. 338. under the float ; these are polyps, or feeding- 
mouths, in different stages of development. The 
polyps (Medusae) to which this set of buds give 
rise are of very different characters ; they are of 
three kinds, and nearly equally distributed along 
the remainder of the axis, no part of the axis 
being reserved for any special kind of polyps ; 
the most prominent kind, and the largest, are 
the Hydra-mouths (Fig. 338), which are the most 
active, and in which we find, at the point of junc- 
tion with the axis, a cluster of long tentacles, along 
the thread of which are fastened, by a short han- 
dle, a knob-like appendage ; these are the tenta- 
cles which are so prominent, and assume such 
manifold attitudes when the community is at rest 

t/ 

or in motion. The polyps are open at the distal extremity, the open- 
ing being frequently expanded like the disk of a leech, or simply flaring 
trumpet-shaped ; they are exceedingly contractile, and sometimes ex- 
pand far beyond the axis in search of food ; they communicate by 
means of a somewhat narrow neck with the main axis, so that the food 
which is taken in by any one of these mouths helps to feed the whole 
community, and circulates freely in the main axis, and in every polyp 
and swimming-bell. The clusters of tentacles are protected by a shield- 
like scale (Deckstiick), to the nature of w r hich I shall refer hereafter ; 
this scale is triangular, with rounded extremities, and through the mid- 
dle of it passes a thin tube, which connects with the main axis, making 
a kind of knee immediately above the point of junction ; the upper 
shield of Fig. 338 shows plainly the mode of connection. The knobs of 

Fig. 338. Cluster of Medusae (feeding polyps) of the first kind formed, in the younger stages, 
with tentacular knob and scale. In the upper part of the figure a closed bud, with an oil-bubble, 
is seen ; this bud is ready to be liberated and become an embryonic community, like Fig. 346. 




NAXOMIA CARA. 205 

this kind of tentacles are sole-shaped bodies, paved with a beautifully 
arranged setting of large lasso-cells, edged in by a large set running 
round the edge (Fig. 339) ; these knobs are partly hollow, a portion of 
the tube of the tentacle extending into it a short distance. 

The second kind of feeding polyps (Medusae) (Fig. 340) resemble 
the first in every respect except the tentacles ; they are, like them, 
attached to the main axis, and protected by a scale, omitted in the 
figure ; at the proximal end of the polyp we find, however, a cluster of 
tentacles of a totally different nature from the club-bearing lashes of 
the first kind ; they take their origin as diverticula of the wall of the 
polyp, as those of the first kind ; they never grow long, scarcely 
extending the length of the polyp, but are twisted closely when fully 
developed, though in their earlier stages they are more corkscrew- 
shaped, and coiled quite loosely. The whole surface of these tentacles 

Fig. 341. 
Fig. 339. 






is covered by a regular pavement of lasso-cells of the same size ; the 
lasso-cells in the young tentacles are only found on the edge ; as they 
increase in length, the tentacles become more thickly covered, until, 
when closely coiled, they have the pavement described above. There 
are generally from five to six (Fig. 340) of these large tentacles, and 
about as many more, in different stages of development, at the base of 
each of these polyps ; while of the first kind of tentacles we rarely 
find more than three long threads, though there is a thick cluster of 
embryonic ones adjoining them ready to develop and take their place 
if any accident should happen to the longer meshes. 

The third kind of polyp (Medusae), which is found along the axis, are 
polyps with closed extremities (Fig. 341), differing besides from the 
others in having only one long, slender tentacle at the proximal ex- 
Fig. 339. Enlarged view of the knob of a tentacle of the first kind of Medusae. 
Fig. 340. The second kind of Medusas, having cork-shaped tentacles. The scales in this and 
following figure are omitted ; they differ in no respect from those of Fig. 338. 

Fig. 341. Third kind of Medusa, having only a single thread-like tentacle, and a closed pro- 
boscis. 



206 



NAXOMIA CARA. 



Fig. 342. 



tremity, and being perfectly colorless ; this tentacle is three or four 
times the length of the polyp, and is covered with patches of small 
lasso-cells scattered irregularly over its surface ; the walls of this polyp 
are thick, and are not capable of extensive expansion or contraction, or 
of any remarkable alteration of shape, as the former kinds. There is 
still a fourth kind of appendage formed here and there along the stem, 
one of which is figured on the top of Fig. 338, which resembles this 
last kind of polyp, being closed, like it, at the extremity, but having 
neither scale nor tentacles of any kind, and in the proximal end of 
which we notice an accumulation of oily matter ; these I simply men- 
tion here, and shall return to them hereafter. 

The new polyps which are added to the community take their origin 
from the cluster of buds situated beneath the swimming-bells ; like the 
swimming-bells, they are formed by the bulging of the wall of the main 
axis (Fig. 342) ; they very soon assume the general aspect of feeding 

polyps, though they remain 
closed at their distal extremity 
after they have attained a con- 
siderable size (p, p'i p", Fig. 
342) ; the scarlet pigment-cells 
make their appearance at a 
very early period, so that we 
are able, in very young buds, 
to recognize the nature of the 
future polyps ; as soon as the 
polyp buds are slightly more advanced than they are in the figure here 
given (Fig. 342), the nature of the tentacular buds at the base, and the 
total absence of pigment-cells in some of the larger closed buds, enables 
us readily to decide to which kind of polyps (Medusas) these different 
buds will give rise ; the peculiar sole-shaped knobs of one of the kinds 
of tentacles are nothing but an expansion of the original divert icul urn 
at the base of the polyp ; the different phases through which the knobs 
pass are very easily followed by examining the various stages of growth 
found in a cluster of tentacles, such as is represented in Fig. 338 (some- 
what enlarged in Figs. 343, 344), until they attain the shape repre- 
sented in Fig. 339. They are at first a narrow bag, with a few scat- 
tered lasso-cells (a, Fig. 343), then the thickness of the wall at the 
extremity increases, the lasso-cells at the same time becoming large 
(6, Fig. 343). In the next stage, when seen in profile, the sac has 
assumed a hook-shaped form (c, Fig. 343), the bend becomes still more 
marked, and the lasso-cells are now arranged in a row along the ex- 
tremity (d, Fig. 343) ; the walls become thicker as the lasso-cells 

Fig. 342. Cluster of Medusae (feeding polyps) in different stages of development, before the 
appearance of the scale or of the tentacles, p, oldest ; />', somewhat younger ; />", still younger. 




NANOMIA CARA. 



207 



become more numerous and larger, the knob assuming more a ladle- 
shape (e, Fig. 344) ; there is then formed a still larger row of lasso-cells, 
extending along the edge, and concealing the others (/, Fig. 344), 
making a kind of binding when seen from above (f/, Fig. 344), where 
we find all the peculiar characteristics of the sole-shaped, lasso-paved 
knob of Fig. 339, the only difference in the older knobs being the 
greater size of the outer row of lasso-cells, and their closer packing, 
which conceals entirely the cavity running into the knob, while it is 
plainly visible in younger tentacles. 

The perfectly free and open communication we find between all the 
parts of the community, except the float, is one of their most striking 
characteristics ; there is not an appendage into which the food taken in 
by any one of these feeding polyps (Medusae) cannot circulate into its 
very extremity ; even the scales, which seem in their full-grown state 



Fig. 344. 





Fig. 345. 




to consist of nothing but a gelatinous shield, with a very narrow tube 
passing through the middle, are, when developing, open pouches leading 
at once into the main cavity of the axis, and even after the buds can 
distinctly be recognized as undeveloped scales (Fig. 345), the cavity 
occupies a much greater part of the scale than in the adult, as is readily 
seen in the different views of one of the scales (, 6, c, Fig. 345). In 
the view from above, a, the triangular shape is already apparent ; a 
profile view, 6, shows its greater thickness than in a fully-developed 
scale, while in an end view, c, it is still quite pentagonal. 

Besides these different kinds of appendages, we find the sexual 
individuals scattered in small clusters of abortive Medusae near the 
lower extremity of the axis, generally in the third nearest the terminal 

Fig. 343. , I, c, (1, tentacular knobs like those of Fig. 330, in different stages of development. 
Fig. 344. <?,/, //, the same tentacular knobs, still further developed. 

In Figs. 343 and 344 all the figures are seen in profile, except I of Fig. 343, and tj of Fig. 344, 
which are seen from the flat side, to show the arrangement of the lasso-cells. 
Fig. 345. Young scale ; seen from above, a : in profile, b ', and endways, c. 




208 NANOMIA CARA. 

polyp ; as has already been shown by Sars in Agalmopsis, .the sexes are 
distinct, so that we have whole communities, the sexual Medusae of 
which are either males or females. There is no great difference be- 
tween the appearance of the male and female Medusae ; they do not 
(as is the case in Agalmopsis, according to Sars) separate from the com- 
munity, and lead an independent existence ; they wither on the stem, 
after having discharged their contents. The Medusae form bunches, 
the single Medusae of which are directly attached to the main axis ; 
they are somewhat pointed in outline, with four tolerably well defined 
rig. 346. chymiferous tubes, resembling quite closely the sessile Me- 
dusae of such Tubularians as Tubularia CouthouyL 

From the observations of Gegenbaur, there can be no doubt 
that many of the Siphonophores are, like Nanomia, developed 
directly from the egg, and that the embryo which comes from 
the egg is one which is identical with those found floating 
about in such immense numbers during the early part of 
June, and which are figured in Fig. 346, consisting of a single closed 
polyp and of an oil-float, separated by a partition, as in the adult (Fig. 
331) ; this simple polyp is to be the axis of the future community. 
But these young Nanomise (Fig. 346) do not all arise from eggs, and 
pass directly into an embryo like Fig. 346 ; we have a second kind 
of development, that of budding. In Fig. 338 there is represented on 
the top an appendage resembling somewhat a polyp without an open- 
ing, having neither tentacle nor protecting scale. A bubble of oil is 
collecting at the, proximal extremity ; as this bubble increases in size, 
the neck which connects the polyp with the main axis gradually 
becomes narrower and narrower, until the connection is finally cut, 
and we have a bud resembling in every respect Fig. 346, which has 
separated from the main community. By keeping in confinement, 
rig. 347. entirely isolated, an adult Nanomia having many of these 

buds along the main axis, I have found after a few days 
a large number of these buds liberated, which had as- 
sumed the shape and structure of Fig. 346, and had 
grown to be similar in every respect to the embryos I 
was fishing from the sea at the same time. From this 
I should infer that we have two broods of adults, those 
which are found in the fall, and which lay eggs in Octo- 
ber and November, and those which are probably formed by budding 
from the older ones during the summer and winter ; the embryos found 
in early summer may have come from the eggs of either of these. 

The young embryos (Fig. 346) readily keep alive in confinement, 
and it is a comparatively easy thing to trace the successive stages of a 

Fi;i. 34G. Youngest Nanomia found swimming on surface. 




Fig. 347. Somewhat more advanced. 



NANOMIA CARA. 



209 



further development ; the terminal Hydra of Fig. 346 increases greatly 
in size ; a number of buds make their appearance on both sides of the 
axis, immediately at the base of the float ; these buds are nothing but 
the rudimentary swimming-bells, the so-called polyps and the tentacles. 
(Fig. 347.) As the young Nanomia grows larger, these buds increase 
in size, and we can soon trace in some of them undoubted polyps, 
w r ith an open mouth, and the rudimentary tentacular knobs accompa- 
nying them ; immediately at the base of these polyps there is a small 
transparent protuberance, the first appearance of the protecting scale. 
The terminal polyp of this diminutive community increases greatly in 
size, becomes open at the extremity, and covered irregularly with large 



Fig. 349. 



Fig. 348. 





Fig. 350. 




patches of scarlet pigment-cells ; the tentacles become longer, and when 
they equal in length that of the community, from six to eight knobs 
hang from the main threads. (Fig. 348.) In somewhat more advanced 
specimens, \ve find protecting scales already quite well developed 
(Fig. 349), and besides many additional polyps in different stages of 
development, such as are figured in Fig. 342 ; the buds immediately 
under the float, the nature of which seemed still doubtful in the last 
stage (Fig. 348), are now seen to be rudimentary swimming-bells, some 
of them nearly as advanced as those represented in Fig. 337 ; these 
rudimentary parts grow now with great rapidity, the clusters of the 

Fig. 348. The terminal Hydra is open, tentacles are developed, as well as clusters of small 
swimming-bells, like those of Fig. 337, and of Medusas (feeding polyps), like those of Fig. 342. 

Fig. 349. Still more advanced Nanomia. 

Fig. 350. Young Nanomia, where we find several Medusas (feeding polyps) of the first kind, 
having all the characters of those found in the adult (Fig. 332), and embryonic swimming-bells. 

NO. ii. 27 



210 NANOMIA CARA. 

different kinds of individuals taking the place we find them occupying 
in the adult ; the swimming-bells are placed immediately under the 
float, and the polyps between them and the primitive polyp. The 
protecting scales increase rapidly, and in Fig. 350 we have a young 
Nanomia having two well-developed polyps, as many scales, and as 
many tentacles, one of the polyps being the first terminal one, and 
the other a lateral polyp, at the base of which are found the rudi- 
mentary tentacles, while immediately under the float we find a cluster 
of rudimentary swimming-bells, as far developed as those of Fig. 337. 

From this point there is no doubt that we have before us a young 
Nanomia, and the future phases of the development are only changes 
of quantity. The various members of the community have, however, 
a very different degree of development. What is particularly charac- 
teristic of the young Nanomia is that it is entirely composed of the 
polyp element, and of the polyps with knobbed appendages ; it is only 
somewhat later that the scales make their appearance, and we then 
have a sufficient number of these polyps added to make quite an exten- 
sive community before any other kind is formed, and before the swim- 
ming-bells are developed. We generally find a couple of large swim- 
ming-bells preceding the appearance of the second kind of polyp (Fig. 
339) ; it is not till still later that the Hydrocysts (Fig. 341), as Huxley 
has called the closed polyps, make their appearance. The remaining 
swimming-bells are slow in their development ; we do not usually find 
more than two in quite large specimens, and it is only in the adult, 
where we find the buds which are to separate as young floats and 
where the sexual individuals have begun to make their appearance, 
that there are from four to six swimming-bells. (Fig. 332.) 

From this slight sketch of the order of succession of the different 
individuals, we have the means of dividing all the Siphonophores into 
three great suborders, according to the degree of development of the 
three principal elements. Lowest are those in which the float has the 
greatest predominance, and in which the different individuals of the 
community appear as secondary appendages, such as Porpita, Velella, 
and Physalia ; in the second suborder we have the various stages of 
combinations of the hydrarium and the swimming-bell elements, in the 
following forms, Rhisophyza, Apolemia, Agalma, Nanomia, Halistem- 
ma, Stephanomia, and Forskalia ; while in the third and highest sub- 
order we find the greatest development of the swimming-bells, accom- 
panied by a reduction in the number of individuals forming a single 
community, and a further specialization of parts not found in the 
preceding orders. The different appendages which are found along 
the axis of these floating Hydroids have been considered by most 
English investigators as simple organs, while the greater number of 
German writers believe them to be different kinds of individuals, form- 



NANOMIA CAR A. 211 

together a community, and not a single animal, as maintained by 

O *f ' o */ 

the former. The solution of this question has been considered in 
various ways by Agassiz, Kolliker, Vogt, Leuckart, Gegenbaur, and 
Huxley. Professor Agassiz, who was the first to show the homology 
existing between one of these floating communities and a fixed com- 
munity of Hydroids such as Hydractinia, has, it seems to me, given 
the correct account of these animals. According to him, and the prin- 
cipal points of this view have afterwards been proved independently 
by Vogt, and also developed further, from Professor Agassiz's lectures, 
by McCrady, a Siphonophore is neither a single animal, and its different 
appendages simply organs, nor, according to the opposite and more 
extreme view of Leuckart, does he push the polymorphism to such an 
extent as to consider all the appendages, such as the tentacles and 
scales, as independent individuals ; he compares one of these commu- 
nities to the different kinds of individuals found in a Hydractinia com- 
munity, and thus shows beyond doubt that the Siphonophorcs are not 
a natural order of the Acalephs, but simply different suborders of the 
order of Hydroids ; the fact that they move about as free communities 
does not separate them from the fixed Hydroids ; it would be as un- 
natural to remove into different orders the free swimming Halcyonoids, 
such as Renilla, Veretillum, and the fixed Gorgonia or Halcyonium. 
It has already been fully shown by Vogt that the swimming-bells of 
Agalma and the like are only Medusae differing from the Hydroid 
Medusa? in the absence of a free proboscis and of an opening commu- 
nicating directly with the surrounding medium. The swimming-bells 
of Nanomia are nothing but Medusa? having complicated chymiferous 
tubes, remaining almost always attached to the community, and per- 
forming their part of the work. They are the locomotive individuals 
of the community ; to them is intrusted the carrying about the whole 
of this fraternity, while different functions belong to the other indi- 
viduals, some of them feeding the community, others serving to repro- 
duce it by budding, while others again reproduce it by laying eggs. 

The nature of the different kinds of polyps found along the axis 
does not seem to have been correctly understood ; w r e can compare 
them, in a general w r ay, to the different kinds of individuals found in 
a Hydractinia community ; it seems to me that the only parts which 
can be homologized to one of these fixed Hydroids are the float, the 
original polyp, and the buds (top of Fig. 338) which drop off. These 
are in reality the floating Hydroid, and the other individuals, developed 
as the axis or original Hydroid becomes larger, are not Polyps like the 
original one, but Medusa? in various stages of development, having a 
different appearance from those we are accustomed to consider as such. 
We have, in the suborders of Siphonophora?, communities of different 
kinds of Medusa?, instead of having communities of different kinds of 

/ o 



912 NANOMIA CARA. 

Hydroids, as in Hydractinia, only these Medusae never separate from 
the original parent-stock from which they are produced. The float 
corresponds to the part of the stem of the fixed Hydroids by which 
they are attached, and the different individuals arising from this single 
Polyp are Medusae. To show the Medusa character of these individ- 
uals, I must preface by saying that the tentacles, the Polyp, and the 
scale are not so many independent individuals, but that these three 
together form one individual, the Medusa. It is true this will appear, 
at first sight, rather doubtful ; we are accustomed to associate with 
our notion of Medusa a regularly-shaped bell, chymiferous tubes, and 
a proboscis. But this is not the universal character of Medusas ; the 
abortive sessile Medusa3 of Sertularians, Campanularians, and Tubula- 
rians are as much Medusae, though they have no proboscis and nothing 
but rudimentary chymiferous tubes, as a free-swimming Sarsia or Bou- 
gainvillia, The moment this is understood, a new light is thrown on 
the nature of the individuals of our community. We find among the 
Hydroids all the stages intermediate between a rudimentary Medusa, 
as that of Laomedea or of Dynamena, and that of a symmetrical Me- 
dusa like Sarsia, We have those in which the proboscis is quite well 
developed, others in which the chymiferous tubes are always rudi- 
mentary, others which are asymmetrical, as Hybocodon, and the differ- 
ent spheromeres of which have not an equal degree of development. 
This mves us the clew to the true understanding of the relation be- 

o 

tween the clusters of tentacles, the scale, and the Polyp ; let us take 
one of these Hybocodon Medusae, cut away the two lateral spheromeres 
of the bell, and at the same time reduce the spheromere which bears 
the long tentacle to its minimum, that is, bring the tentacle to the 
point of junction of the proboscis and of the chymiferous tubes, cut 
the remaining spheromere in any shape we please, triangular or pen- 
tagonal, and we have a Medusa identical in every respect to those of 
our community. The cluster of tentacles corresponds to the single 
tentacle, the scale with its tube corresponds to the remaining sphero- 
mere and its chymiferous tube, while the proboscis and the Polyp are 
identical, and perform one and the same function. The fact that there 
is or is not a chymiferous tube extending through the scale, as in Fig. 
338, does not invalidate this homology ; for the chymiferous tubes in 
many Hydroid Medusae are exceedingly rudimentary, and in that case 
it would only be carrying out for free Hydroids what has become 
perfectly familiar to us among the fixed Hydroids. 

By reducing this proposition to a mathematical form, I may perhaps 
give the reader a better idea of the process I am endeavoring to 
explain, by supposing an equation of the nth degree to represent the 
formula of a Hydroid Medusa, the roots of which are represented by 
the diflerent spheromeres ; they all become imaginary in our Nanomia, 



NANOMIA CAR A. 213 

with the exception of one root, which is positive, and this would repre- 
sent the only remaining spheromere, that of the Deckstuck. 

If this view is correct, it is evident that the opinion of Huxley, who 
considers the scale as homologous to the urn of Campanularians, can- 
not be sustained, I have already hinted at the similarity of the em- 
bryonic Nanomia, in the stage of Fig. 347, when it consists of only the 
large Polyp and the float, with the early stages of the fixed Hydrarium 
of Melicertum, where we have at first a single Polyp, from which are 
developed, by budding, the branches and the other kinds of individuals 
of the community ; supposing this community, instead of fixing itself, 
as it does, to remain movable, the base of the stem to expand into a 
float and become separated from the main cavity, we should have a 
Siphonophore. The discovery by McCrady and Stimpson of the float- 
ing Hydrarium of Nemopsis and Acaulis, where the Medusa} are closely 
related to genera the Hydrarium of which is always fixed, reduces still 
further the distinction which has been made of Polypi Nechali. And 
when we find that there are genuine Medusae (Dysmorphosa) which 
for four generations reproduce themselves by budding from the pro- 
boscis, exactly in the same way in which we find additional individuals 
arising along the walls of the original Polyp among Physophoridre., we 
are at a loss to find any distinctions to separate the Siphonophores 
from the true Hydroids, and we cannot consider them as anything 
but floating Hvdroid communities. 

o */ 

Massachusetts Bay, Nahant, and Newport, R I. (A. Agassiz). 
Cat. No. 365, Nahant, Mass., September, 1862, A. Agassiz. 
Museum Diagram, No. 27, after A. Agassiz. 



214 



PORPIT.E. 



SUBORDER PORPIT^E GOLDF. 

Porpitcc GOLDF. Handb. cler Zool. 1820. 

Porpi/ce and Physalm AGASS. Cont. Nat. Hist. U. S., IV. p. 366. 1862. 

Chondropliorce CHAM, et EYS. Acta Nova, X. 

From a comparison of the young stages of Nanomia with the known 
SiphonophoraB, I have been induced to extend the limits of this sub- 
order so as to include Physalia, forming thus three suborders among 
Hydroids of the old order of Siphonophorse, the Diphyce, the Physo- 
phora?, and the Porpitae. 



Family PHYSALID^E Brandt. 

PhysaUdce BR. ; in Mem. Acad. St. Petcrsb., p. 236. 1835. 
Physalidce AGASS. Cont. Nat. Hist. U. S., IV. p. 366. 1862. 



PHYSALIA LAMK. 

P1i>imUa LAMK. An. s. Vert., HI. p. 89. Second Edition. 

Arethusa BROWN. Nat. Hist. Jam. 

Arethusa LESS. Zooph. Acal., p. 530. 1843. 

Physalia AGASS. Cont. Nat. Hist. U. S., IV. pp. 335, 366. 1862. 



Fig 351. 





rnV 




Physalia Arethusa TIL. 

Physalia Arethusa TIL. ; in Krusenst. Reise, PI. 23, Figs. 1-6. 1813. 
Physalia Arethusa OLF. ; in Mem. Berl. Acad., PL 1. 1832. 
Physalia Arethusa AGASS. Cont. Nat. Hist. U. S., IV. pp. 335, 367, 

PL 35. 1862. 

Physalia pelasoica Bosc. Hist. Nat. d. Vers, II. p. 168. 
Physalia aurigera McCR. Gymn. Charleston Harbor, p. 74. 

Physalia Arethusa (Fig. 351) is probably carried 
by the Gulf Stream as far as the Azores. A spe- 
cies has been described by Lesson as Physalia 
azoricum, which may be only the young of Phy- 
salia Arethusa. (See Voyage de la Coquille, Plate 
5, Fig. 4.) To facilitate the comparison of the 
different kinds of individuals found in communi- 
ties of this family with those of Nanomia, groups 

Fig. 351. Physalia Arethusa Til. Figs. 351-354 are copied from 
Professor Agassiz's Contributions, a, blunt end of air-sac supporting 
the community ; &, open end of air-sac ; c, crest of air-sac ; m, bunches 
of single individuals ; n, tentacle contracted ; t, t, tentacles of the lar- 
gest kind expanded. 



PHYSALIA ARETHUSA. 



215 



of Hydrae and of Medusa? (Figs. 352, 353, 354) are introduced 
here. 

Fig. 352. 
Fig. 353. 






Charleston (McCrady) ; Gulf of Mexico (Brown, Sloane) ; Florida 
(L. Agassiz) ; Cape Cod (A. Agassiz) ; Martha's Vineyard (W. H. 
Forbes). 

Cat. No. 305, Florida, 1850, L. Agassiz. 

Cat. No. 306, Florida, 1850, L. Agassiz. 

Cat. No. 307, Florida, 1850, L. Agassiz. 

Cat. No. 308, Key West, Fla., February, 1858, L. Agassiz. 

Cat. No. 309, Key West, Fla., March, 1858, L. Agassiz. 

Cat. No. 310, Tortugas, Fla., February, 1858, L. Agassiz. 

Cat. No. 311, New Providence, Bahamas, April, 1861, F. G. Shaw. 

Cat. No. 312, Mobile, Alabama, L. Agassiz. 

Cat. No. 313, 40 N. Lai, 60 W. Long., Captain W. H. A. Putnam. 

Cat. No. 314, Naushon, Mass., 1861, W. H. Forbes. 

Cat. No. 325, Tortugas, Fla., March, 1858, L. Agassiz. 

Cat. No. 385, Beaufort, N. C., May, 1863, A. S. Bickmore. 

Cat. No. 386, Bermudas, A. S. Bickmore. 

Museum Diagram, No. 28, after L. Agassiz. 

Fig. 352. Bunch of single Hydrae, and clusters of Medusae, of Physalia Arethusa Til. ft, &, 
Hydras, with their tentacles, c, c ; d, d, bunches of tentacles. 

Fig. 353. Bunch of Hydra, a, hollow base of attachment communicating with air-sac ; b, 1, 5, 
single Hydrae ; c, e, tentacles. 

Fig. 354. Bunch of Medusas in various stages of development, a, hollow base of attachment ; 
I, Hydra ; d, d, Medusa} buds. 



216 



VELELLID.E. 



Family VELELLID^E Esch. 

Velellidce ESCH. (resir. Agass.). Syst. d. Acal., p. 165. 1829. 

Velellce LESS. Zooph. Acal., p. 560. 1843. 

Velellidce AGASS. Cunt. Nat. Hist. U. S., IV. p. 366. 18G2. 



VELELLA LAMK. 

Velella LAMK. Anim. s. Vert., II. 1819. 

Velella LESS. Zooph. Acal., p. 5G2. 1843. 

Velella AGASS. Cont. Nat. Hist. U. S., IV. p. 3G6. 18C2. 

Rataria ESCH. Syst dor Acal., p. 1G6. 1829. 

Chrysomitra GEGENB. ; in Zeit. f. Wiss. Zool., p. 231. 1856. Medusa. 

Linuche Escn. Syst. dcr Acal., p. 91. 1829. Medusa. 

? Rataria PAGENST. ; in Zeit. f. Wiss. Zool., XII. p. 496. 18G3. 



Velella mutica Bosc. 

Velella mutica Bosc. Hist. Nat. d. Vers, II. p. 158. 
Velella mutica LESS. Voyage de la Coquille, PI. 6. 1829. 
Velella mutica LESS. Zooph. Acal., p. 571. 1843. 
Velella mutica AGASS. Cont. Nat. Hist. U. S., IV. p. 366. 



1862. 



The free Medusa of Velella resembles so exactly that produced by 
some of the Tubularians Euphysa and Globiceps, for example that 
it would seem the most natural thing to place these Medusae among 
Tubularians, as McCrady has done ; but the polymorphism of the 





Fig. 357 




Hydne (Fig. 355) and the presence of the float (Fig. 356) associate 
the Hydrarium with the Porpitse. The free Medusa is but another 
link showing how close is the relation between the floating and fixed 
Hydroids. The Medusa figured here (Fig. 357) is one which has just 
freed itself. The chymiferous tubes, as well as the proboscis, are of a 



. 



355. An enlarged view of one of the fertile Hydrae of Velella. a, base of attachment of 
Hydra ; &, end of Hydra ; d, d, clusters of Medusae. All these figures are copied from Professor 
Agassiz's Contributions, Vol. III. 

Fig. 356. Velella, seen from below, to show the Hydrae. m, opening, so-called mouth ; a, fer- 
tile Hydrae situated between the mouth and the outer tentacles, the sterile Hydras. 

Fig. 357. Magnified view of a free Medusa of Velella mutica Bosc. o, proboscis ; b, chymif- 
erous tube ; c, circular tube. 



VELELLA SEPTENTRIONALIS. 217 

brilliant ochre color. Professor Agassiz has observed this Medusa four 
days after it became free, when the Medusa had become quite globu- 
lar, having lost entirely its elongated shape. 

Long Island Sound (A. Agassiz) ; Gulf of Mexico (Bosc) ; Coast of 
Florida (L. Agassiz). 

Cat. No. 296, Florida, 1850, L. Agassiz. 

Cat. No. 297, Fort Jefferson, Fla., April, 1859, Dr. D. W. Whitehurst. 

Cat. No. 298, Key West, Fla., March, 1858, J. E. Mills. 

Cat. No. 299, Cape Florida, April, 1858, G. Wurdeman. 

Cat. No. 300, Cape Florida, G. Wurdeman. 

Cat. No. 301, Tortugas, Fla., April 2, 1858, L. Agassiz. 

Cat. No. 302, Tortugas, Fla., April, 1858, J. E. Mills. 

Museum Diagram, No. 27, after L. Agassiz. 



Velella septentrionalis ESCH. 

Velella septentrionalis ESCH. Syst. der Acal., p. 171, PL 15, Fig. 1. 1829. 

Numerous specimens were collected at the entrance of the Straits 
of Fuca. The proportions of this species are quite different from 
those of our West Indian V. mutica. The figure given by Eschscholtz 
gives a good idea of the almost square outline of the float. 

In company with V, se^)tentrionalis was always found a Physalia, 
which I have been unable to refer to any of the described species. 
As the specimens of both were lost, they are mentioned here for the 
sake of the geographical distribution of these animals. 

Northwest coast of America (Eschscholtz) ; Straits of Fuca (A. Ag- 
assiz, October, 1859) ; San Francisco Bar (A. Agassiz, October, 1859). 



NO. ii. 28 



218 PORPITIDvE. 



Family PORPITID^l Guild. 

Porpitirlcc GUILD. ; in Zool. Journ., XI. p. 403. 
Velellidce ESCH. (p.p.). Syst. der Acal, p. 165. 1829. 
Porpitidce AGASS. Cont. Nat. Hist. U. S., IV. p. 366. 1862. 
Porpitce LESS. Voyage de la Coquille, II. p. 55. 1829. 



PORPITA LAMK. 

Porpita LAMK. Anira. s. Vert., II. 1819. 

Porpita LESS. Zooph. Acal., p. 583. 1843. 

Porpita AGASS. Cont. Nat. Hist. U. S., IV. p. 366. 1862. 

PolybracJiiona GUILD. ; in Zool. Journ., XI. 

Ratis LESS. Zool. de la Coquille. 1829. 

Acies LESS. Zool. de la Coquille. 1829. 

? Armenistarium COSTA. Faune de Naples. 



Porpita linnseana LESS. 

Porpita linnaana LESS. Zooph. Acal., p. 588. 1843. 
Poli/bracJiionia linnceana GUILD.; in Zool. Journ., XI. Fig. 
Porpita linnceana McCit. Gymn. Charleston Harbor, p. 42. 
Porpita linnceana AGASS. Cont. Nat. Hist. U. S., IV. p. 366. 1862. 
? Porpita atlantica LESS. Voy. de la Coquille, PI. 7, Fig. 2. 

West Indies (Guilding) ; Florida (L. Agassiz) ; Charleston, S. C. 
(McCrady). 

Cat, No. 289, Fort Jefferson, Fla,, April, 1859, Dr. Whitehurst. 

Cat, No. 290, Pensacola, Fla. 

Cat, No. 291, Key West, Fla., L. Agassiz. 

Museum Diagram, No. 27, after L. Agassiz. 



TABULATE. 



219 



SUBORDER TABULATE AGASSIZ. 

Tabulatce AGASS. Sill. Journ., XXVI. p. 140. 1858. 
Corallaria Tabulata EDW. & HAIME. Archiv du Mus., V. 
Madreporaria Tabidata EDW. & HAIME. Hist. Corall., III. p. 223. 1860. 
Tabulatce AGASS. Cont. Nat. Hist. U. S., IV. p. 292. 1862. 



Family MILLEPORID^E Agass. 

MILLEPORA LINN. 

Millepora LINN. Syst. Nat. 



Millepora alcicornis LIN. 

Millepora alcicornis LIN. Syst. Nat., X. 1758. 

Millepora alcicornis DANA. U. S. Ex. Exp. Zoophytes, p. 543. 

Millepora alcicornis EDW. & HAIME. Hist. Corall., III. p. 228. 

Milfepora alcicornis AGASS. Cont. Nat. Hist. U. S., III. p. 292, PI. 15, Figs. 3-13. I860. 

Millepora alcicornis VERRILL ; in Bull. Mus. Comp. Zool., p. 59, No. 3. 1864. 

The absence of radiating partitions in the Tabulate seems to show, 
without much doubt, that their true place is among the Hydroids. It 
is true that Professor Agassiz has not observed the Medusae buds on 
the specimens he has figured (Fig. 358), yet the Hydroid character 
of the animal, and their similarity to Halocharis-like Hydroids, is very 



Fig. 358. 



Fig. 359. 



Fig. 360. 






Os 



striking. It certainly is not more wonderful to have among Acalephs 
Hydroids which should deposit hard limestone parts (Figs. 359, 360), 
as Millepora and the like, than it is to find among the Polyps animals 
in which we find partitions of every stage of hardness, from a gelati- 
nous or a horny nature, to the most solid deposits of limestone. We 
have already something of the same diversity in the formation of the 

Fig. 358. Magnified view of extended Hydroids of Millepora. , a, small Hydroids ; b, larger 
ones ; m, mouth ; /, tentacles. 

Fig. 359. Branch of Millepora alcicornis ; natural size. 

Fig. 360. Transverse section of branch, a, a, pits of Hydroids. 



220 MILLEPORA ALCICORNIS. 

different kinds of sheaths of the Sertularians and of the Campanula- 
rians, and especially in the great development of the horn-like net- 
work forming the base of a Hydractinia colony, and the limestone 
floors deposited by the base of the animal of Millepora is only an 
extreme case for Acalephs, similar to the solid radiating partitions of 
the Madrepores among Polyps. 

Tortugas, Fla. (L. Agassiz). 

Cat. No. 382, Tortugas, Fla., March, 1858, L. Agassiz. 



GEOGRAPHICAL DISTRIBUTION. 



FOR the sake of showing more strikingly the character of the dif- 
ferent Acalephian Faunae of our coasts, lists have been prepared 
embracing several species not enumerated in the Catalogue, to give 
a better idea of the peculiar stamp of the regions into which our coast 
has been divided. No names are here given to these faunal divisions, 
as in a forthcoming number of the Museum Catalogue the limits and 
nomenclature of our Marine Faunae will be fully discussed. For the 
present I shall simply point out in a general manner some of the more 
interesting points of the distribution of our Acalephs. Several species 
have a very extensive range ; on the Atlantic side, from Greenland to 
Long Island Sound, and from Grand Man an to Charleston, South Caro- 
lina. In the Pacific Ocean we find species which range from Kamt- 
schatka to the northern part of California. Within these extensive 
belts there are other species more limited in range, extending only 
from Massachusetts Bay to Eastport, from Charleston to Cape Cod, 
from San Francisco to the Gulf of Georgia, or from the Gulf of Georgia 
to Behring's Straits ; while a third series of species is still more lim- 
ited, extending only along such portions of the shores as Nova Scotia, 
Massachusetts Bay, Long Island Sound, the coast of Southern California, 
the Gulf of Georgia, and the like. 

The areas of distribution of the different species overlap and enclose 
one another so as to give us for the character of the Fauna of any par- 
ticular locality three different elements of distribution ; first, the cos- 
mopolitan species, spreading over wide areas ; next, the species which 
range over more limited areas ; and finally, the local species scattered 
in the areas of the limited species. It is the peculiar combination of 
these three elements which gives to a special locality what has been 
called its faunal character, but owing to the intricate crossing, overlap- 
ping, and enclosing of these areas, we find it nearly impossible to draw 
lines along our coast which should embrace homogeneous elements. 
Such areas are found on our coast, extending approximately from 
Greenland to the northern part of Nova Scotia, from Nova Scotia to 
the northern part of Maine, and from Massachusetts Bay to Cape Cod ; 
the coast of Long Island Sound and New Jersey, as for as Cape Hat- 



222 



GEOGRAPHICAL DISTRIBUTION. 



teras, presents features of its own ; the coast of the Carolines and 
Georgia has likewise distinct faunal features, while Florida and the 

o 

West Indies have each their peculiar Acalephs, though the boundaries 
of the distribution of many of the species, found in each of those divis- 
ions, extend far beyond the limits we have here assigned to the regions. 
On the Pacific side of North America, we find the great belt of the 
Northern Pacific extending from the shores of Kamtschatka to British 
North America ; the inland sea behind Vancouver's Island and the main- 
land has a characteristic fauna, and along the coast of California itself 
still different Medusae are found. The association of the three elements 
mentioned above being so different at certain localities, we naturally 
come to look upon them as centres from which the species of a fauna 
are derived, while in reality it is only the peculiar combinations of the 
geographical extension of each species which give the distinguishing 
features to each locality. 



NORTH PACIFIC. 

* 

SITKA, ALEUTIAN ISLANDS, BEHRING'S STRAITS, KAMTSCHATKA. 



Bolina scptcntrionalis Mert. 
Janira cucumis Less. 
Dryodora glandiformis Ag. 
Phaccllophora camtschatica Br. 
Cyanea Postelsii Br. 
( '//mica ferruginea Esch. 
Pelagia Brandtii Ag. 
Polybostricha helvola Br. 
Melanaster Mertensii Ag. 
^Eginopsis Laurentii Br. 
Trachynema camtschaticum A. Ag. 
Staurophora Mertensii Br. 
Diphasia (H /r/ra-like) 
Sertularia (a&iema-like) 
Cotulina Greenei A. Ag. 
Tli niaria (th /a-like ) 
Bougainvillia Mertensii Ag. 
Proloscidactyla flavidrrata Br. 



Behring's Straits. 
Sitka. 

Behring's Straits. 
Kamtschatka. 
Sitka. 

Aleutian Islands ; 
Aleutian Islands. 
Aleutian Islands. 
Kamtschatka. 
Behring's Straits. 
Kamtschatka. 
Aleutian Islands. 
Behring's Straits. 
Behring's Straits. 
Behring's Straits. 
Behring's Straits. 
Behring's Straits 
Kamtschatka. 



Kamtschatka. 



Mertens. 

Mortens. 

Mertens. 

Mertens. 

Mertens. 

Eschscholtz. 

Mertens. 

Mertens. 

Mertens. 

Mertens. 

Mertens. 

Mertens. 

W. Stimpson. 

W. Stimpson. 

W. Stimpson. 

W. Stimpson. 

Mertens. 

Mertens. 



GULF OF GEORGIA, W. T. 



microptera A. Ag. 
Pleuroibrachia Bacliei A. Ag. 
Idyia cyatJnna A. Ag. 
Hecccedeconima amliiguitm Br. 
Cyanea Postelsii Br. 
Trachynema camtschaticum A. Ag. 
Oceania gregaria A. Ag. 
Crematostoma flava A. Ag. 
la ccerulescens Br. 
ciliata Eseh. 
Laomedea pacifica A. Ag. 



A. Agassiz. 
A. Agassiz. 
A. Agassiz. 
A. Agassiz. 
A. Agassiz. 
A. Agassiz. 
A. Agassiz. 
A. Agassiz. 
A. Agassiz. 
A. Agassiz. 
A. Agassiz. 



Polyorcliis penicillata A. Ag. 
Laodicea eellularia A. Ag. 
Gonionemus vertens A. Ag. 
Melicertum georgicum A. Ag. 
Bougainvillia Mertensii Ag. 
Stomotoca atra A. Ag. 
Proboscidactyla flavicirrata Br. 
Coryne rosaria A. Ag. 



Velella septentrionalis Esch. 
Porpita sp. 



A. Agassiz. 
A. Agassiz. 
A. Agassiz. 
A. Agassiz. 
A. Agassiz. 
A. Agassiz. 
A. Agassiz. 
A. Agassiz. 
A. Agassiz. 
A. Agassiz. 
A. Agassiz. 



GEOGRAPHICAL DISTRIBUTION. 



223 



SAN FRANCISCO, CALIFORNIA. 



Aurelia labiata Cham. & Eys. 
Phacellbphora camtxchatica Br. 
Polybostricha helvola Br. 
Mclanaster Mertensii Ag. 
Laomedea rigida A. Ag. 
Laomedea pacifica A. Ag. 
Poli/orchis penicillata A. Ag. 
Aglaophenia frctHciscana A. Ag. 
Di/ihasia corniculata A. Ag. 
Sertularia anyuina Trask. 



A. Agassiz. 
A. Agassiz. 
A. Agassiz. 
A. Agassiz. 
A. Agassiz. 
A. Agassiz. 
A. Agassiz. 
A. Agassiz. 
Murray. 
Trask. 



Sertularia graciiis A. Ag. 
Sertularia furcata Trask. 
Sertularia turgida Trask. 
Cotulina Greenei A. Ag. 
Bougainvillia Mertensii Ag. 
Coryne rosaria A. Ag. 
Parip/m microcephala A. Ag. 
Thainnocnidia tubularoides A. Ag. 
II//i/ra tennis Ayres. 
Physalia sp. 



Trask. 

Trask. 

Trask. 

Murray. 

A. Agassiz. 

A. Agassiz. 

A. Agassiz. 

A. Agassiz. 

Ayres. 

A. Agassiz. 



WEST INDIES. 



Oc i/roe maculata Rang. 
Jtlyia ovata Less. 
Polyclonia frondosa Ag. 
Pilania cyanella Per. et Les. 
Clytia (woZw&iZis-like) . 
Laomedea (antipathes-^ke), 
Laomedea (gracilis-]i]s.e). 
Aglaophenia pelasgica McCr. 
Aglaophenia trlfida Ag. 
Aglaophenia ac in aria Duch. 
Aglaopkenia atlantica Duch. 



Rang. 

Brown. 

Poey. 

Swartz. 

Duchassaing. 

Duchassaing. 

Weinland. 

Weinland. 

Weinland. 

Duchassaing. 

Duchassaing. 



Dynamena ostrearum Duch. 
Dynamena (rft'sft'cAa-like). 
Zelleria simplex Duch. 
TuJmlaria Ehrcnlergii Duch. 
Tubularia Lamourouxii Duch. 
Tubularia glandulosa Duch. 
Tubularia pinnata Duch. 
Physalia Arethusa Til. 
Velclla mutica Bosc. 
Porpita linnceana Less. 
M'dlepora alcicornis Lin. 



Duchassaing. 

Duchassaing. 

Duchassaing. 

Duchassaing. 

Duchassaing. 

Duchassaing. 

Duchassaing. 

Brown. 

Brown. 

(iuilding. 

Linntcus. 



FLORIDA REEF. 



Bolina vltrea Ag. 
Idyopsis qffinis Ag. 
Polyclonia frondosa Ag. 
A urelia marginalis Ag. 
Pelagia cyanella Per. et Les. 
Liriope tenuirostris Ag. 
Clytia (inter m edia-l'ike) . 
Clytia (yo/w/7.y-like). 
Orthopyxis (poterium-like). 
Laomedea (ampJiora-Mke). 
Laomedea (dichotoma-Uke), 
Rhegmatodes jloridanus Ag. 
Zygodactyla cyanea Ag. 
Eirene ccerulea AST. 



L. Agassiz. 
L. Agassiz. 
L. Agassiz. 
L. Agassiz. 
L. Agassiz. 
L. Agassiz. 
L. Agassiz. 
L. Agassiz. 
L. Agassiz. 
L. Agassiz. 
L. Agassiz. 
L. Agassiz. 
L. Agassiz. 
L. Agassiz. 



Eutiina pyramldalis Ag. 
Dynamena sj). 
Pasithea sp. 

Aglaophenia pelasgica McCr. 
Aglaophenia trijida Ag. 
Plumularia quadridens McCr. 
Plumularia sp. 
Nigelastrum sp. 
Pennaria gibbosa Ag. 
Paripha cristata Ag. 
Phi/sal ia Arethusa Til. 
Velclla mutica Bosc. 
Porpita liniuaana Less. 
M'dlepora alcicornis Linn. 



L. Agassiz. 
L. Agassiz. 
L. Agassiz. 
L. Agassiz. 
L. Agassiz. 
L. Agassiz. 
L. Agassiz. 
L. Agassiz. 
L. Agassiz. 
L. Agassiz. 
L. Agassiz. 
L. Agassiz. 
L. Agassiz. 
L. Agassiz. 



CHARLESTON, SOUTH CAROLINA. 



Bolina littoralis McCr. 
Mnemiopsis Gardeni Ag. 
Beroe punctata Esch. 
Idyopsis ('larJcii Ag. 
Stomolophus meleauris Ag. 
Cyanea versicolor Ag. 
Foveolia octonaria A. Ag. 
Persa incolorata McCr. 
Liriope scutigera McCr. 



McCrady. Oceania folleata Ag. McCrady. 

L. Agassiz. Eucheilota ventricularis McCr. McCrady. 

McCrady. Clytia bicophora Ag. McCrady. 

L. Agassiz. Platypyxis cylindrica Ag. L. Agassiz. 

L. Agassiz. Eucope divaricata A. Ag. L. Agassiz. 

L. Agassiz. Obelia commissuralis McCr. McCrady. 

McCrady. Eirene gibbosa Ag. McCrady. 

McCrady. Eufiitia mira McCr. McCrady. 

McCrady. Eutitna variabilia McCr. McCrady. 



224 



GEOGRAPHICAL DISTRIBUTION. 



Aglaophenia pelasgica McCr. 
Aglaophenia trijida Ag. 
Aglaophenia tricuspis McCr. 
Plumularia quadridens McCr. 
Plumularia (CathariiiaAlliv). 
Dynamena cornicina McCr. 
Diphasia (nigra-Uke). 
Nemopsis Bacliei Ag. 
Margelis carolinensis Ag. 
Eudendrium ramosum McCr. 
Turritopsis nutricida McCr. 
Stomotoca apicata Ag. 
Willla ornata McCr. 



McCracly. 
L. Agassiz. 
McCrady. 
McCrady. 

L. Agassiz. 

L. Agassiz. 

L. Agassiz. 

McCrady. 

McCrady. 

McCrady. 

McCrady. 

McCrady. 

McCrady. 



Dlpurena strangulata McCr. "MeCrady. 

Dipurena cervicata McCr. McCrady. 

Corynilis Agasshii McCr. McCrady. 

Gemmaria gemmosa McCr. McCrady. 

Pennaria tiarella McCr. McCrady. 

Ectopleura turricula Ag. McCrady. 

Paripha cristata Ag. L. Agassiz. 

Hydractinia polyclina Ag. McCrady. 

Eudoxia (data McCr. McCrady. 

Diphi/es pusilla McCr. McCrady. 

Physalia Arethusa Til. McCrady. 

Velella mutica Bosc. McCrady. 

Porpita linnceana Less. McCrady. 



BUZZARD'S BAY AND LONG ISLAND SOUND. 



Mnemiopsis Leidyi A. Ag. 
Lesueuria hyboptera A. Ag. 
Pleurobrachia rhododactyla Ag. 
Cijanea arc/tea Per. et Les. 
Cyanea fuli-a Ag. 
Dactylometra quinquecirra Ag. 
Trachynema digitale A. Ag. 
Oceania languida A. Ag. 
Euclieilota ventricidaris McCr. 
Eucheilota duodecimals A. Ag. 
Clytia roliibilis A. Ag. 
Clytia bicophora Ag. 
Platypyxis cylindrica Ag. 
Eucope diaphana Ag. 
Obelia commissuralis McCr. 
Laomedea ampJiora Ag. 
Rhegmatodes tennis A. Ag. 
Zygodactyla groenlandica Ag. 
jEquorea albida A. Ag. 
Eutima limpida A. Ag. 
Lafata calcarata A. Ag. 
Dynamena pumila Laiiix. 



A. Agassiz. 
A. Agassiz. 
A. Agassiz. 
A. Agassiz. 
A. Agassiz. 
A. Agassiz. 
A. Agassiz. 
A. Agassiz. 
A. Agassiz. 
A. Agassiz. 
A. Agassiz. 
A. Agassiz. 
A. Agassiz. 
A. Agassiz. 
A. Agassiz. 
A. Agassiz. 
A. Agassiz. 
A. Agassiz. 
A. Agassiz. 
A. Agassiz. 
A. Agassiz. 
A. Agassiz. 



Sertularia cupressina Lin. 
Nemopsis Bachei Ag. 
Bougainvittia super-ciliaris Ag. 
Margelis carolinensis Ag. 
Eudendriwm dispar Ag. 
Eudendrium tenuc A. Ag. 
Dysmorphosa fulgurans A. Ag. 
Modeeria sp. 

Turritopsis nutricida McCr. 
Stomotoca apicata Ag. 
Claca Icptosti/la Ag. 
Willla ornata McCr. 
Dipurena cornea A. Ag. 
. Gemmaria gemmosa McCr. 
Pennaria tiarella McCr. 
Cordylophora sp. 
Ectopleura ocliracea A. Ag. 
Hybocodon proltfer Ag. 
Hydra carnca Ag. (Conn.) 
Hydractinia polycfina Ag. 
Nanomia cara A. Ag. 
Physalia Arethusa Til. 



Leidy. 

L. Agassiz. 

Leidy. 

A. Agassiz. 

A. Agassiz. 

A. Agassiz. 

A. Agassiz. 

A. Agassiz. 

A. Agassiz. 

A. Agassiz. 

Leidy. 

A. Agassiz. 

A. Agassiz. 

A. Agassiz. 

Ayres. 

Leidy. 

A. Agassiz. 

A. Agassiz. 

L. Agassiz. 

A. Agassiz. 

A. Agassiz. 

A. Agassiz. 



MASSACHUSETTS BAY. 



Bolina alata Ag. 
Lesueuria hyboptera A. Ag. 
Mertensia ocum Morch. 
Pleurobrachia rhododactyla Ag. 
Idyia roseola Ag. 
A urelia flavidula Per. et Les. 
Cyanea arctica Per. et Les. 
Campanella pachyderma A. AO-. 
Trachynema d if/if ale A. Ag. 
Halimocyathus platypus H. J. C. 
Manama auricula H. J. C. 
Lucernaria quadricornix Miill. 
Haliclystus auricula II. J. C. 
Tiaropsis diademata Ag. 



L. Agassiz. 
A. Agassiz. 
A. Agassiz. 
L. Agassiz. 
L. Agassiz. 
L. Agassiz. 
L. Agassiz. 
A. Agassiz. 
A. Agassiz. 
II. J. Clark. 
H. J. Clark. 
L. Agassiz. 
L. Agassiz. 
L. Agassiz. 



Oceania languida A. Ag. 
Wrightia sp. 
Clytia intermedia Ag. 
Clytia bicophora Ag. 
Clytia volubilis A. Ag. 
Platypyxis cylindrica Ag. 
Orthopyxis poterium Ag. 
Eucope diaphana Ag. 
Eucope alternata A. Ag. 
Eucope parasitica A. Ag. 
Eucope polygena A. Ag. 
Eucope pyriformis A. Ag. 
Eucope articulata A. Ag. 
Eucope fusiformis A. Ag. 



A. Agassiz. 
L. Agassiz. 
L. Agassiz. 
L. Agassiz. 
L. Agassiz. 
L. Agassiz. 
L. Agassiz. 
L. Agassiz. 
A. Agassiz. 
A. Agassiz. 
A. Agassiz. 
A. Agassiz. 
A. Agassiz. 
A. Agassiz. 



GEOGRAPHICAL DISTRIBUTION. 



225 



Obclia commissuralis McCr. 
Laomedea amphora Ag. 
Laomedea gigantea A. Ag. 
Laomedea reptans Lamx. 
Laomedea sp. 

Stomdbfachium tentaculatuin Ag. 
Ilalopsis ocellata A. Ag. 
Halopsis cruciata A. Ag. 
Zygodfictyla groenlandica Ag. 
Zygodactyla crassa A. Ag. 
Tim a fonriosa Ag. 
Lafaea cornuta Lamx. 
Lafiea dumosa Sars. 
Mellcertum campanula Per. et Lcs. 
Staurophora laciniata Ag. 
Ptychogena lactea A. Ag. 
Plumulana arborea Des. 
Dynamena pumila Lanix. 
Dyphasia fallax Ag. 
Dypltasia rosacea Ag. 
Sertularia cupressina L. 
Sertularia argentca Ell. & Sol. 
Sertularia f ale at a L. 
Sertularia myriophyllum L. 
Amphitrocha rugosa Ag. 
Cotulina tricuspidata A. Ag. 



L. Agassiz. 
L. Agassiz. 
H. J. Clark. 
L. Agassiz. 
L. Agassiz. 
L. Agassiz. 
A. Agassiz. 
A. Agassiz. 
L. Agassiz. 
A. Agassiz. 
L. Agassiz. 
A. Agassiz. 
A. Agassiz. 
L. Agassiz. 
L. Agassiz. 
A. Agassiz. 
Desor. 
L. Agassiz. 
L. Agassiz. 
L. Agassiz. 
L. Agassiz. 
L. Agassiz. 
L. Agassiz. 
L. Agassiz. 
L. Agassiz. 
L. Agassiz. 



Cotulina tamarisca A. Ag. 
Haleciurn haled num Johnst. 
Bougainvittia superciliaris Ag. 
Emit ndrium dispar Ag. 
Eudendrium tenue A. Ag 
Eudendrium sp. 
Lizzia grata A. Ag. 
Dysmorphosa fuUjurans A. Ag. 
Turris vesicaria A. Ag. 
Turritopsis sp. 
Ithizogeton fusiformis Ag. 
Clava leptostyla Ag. 
Coryne mirabilis Ag. 
Sy n diet yon reliculatum A. Ag. 
Gemmaria cladophora A. Ag. 
Pennaria tiarella McCr. 
Euphysa virgulata A. Ag. 
Hybocodon prolifer Ag. 
Corymorpha pendula Ag. 
Paripha crocea Ag. 
Thamnocnidia spectabilis Ag. 
Thamnocnidia tenella Ag. 
Tulmlaria CoutJiout/i Ag. 
Hydra f/racilis Ag. (Mass.) 
Hydractinia polyclina Ag. 
Nanomia cara A. Ajr. 



L. Agassiz. 
L. Agassiz.. 
L. Agassiz. 
L. Agassiz. 
A. Agassiz. 
A. Agassiz. 
A. Agassiz. 
A. Agassiz. 
A. Agassiz. 
A. Agassiz. 
L. Agassiz. 
L. Agassiz. 
L. Agassiz. 
A. Agassiz. 
A. Agassiz. 
A. Agassiz. 
A. Agassiz. 
L. Agassiz. 
L. Agassiz. 
L. Agassiz. 
L. Agassiz. 
L. Agassiz. 
L. Agassiz. 
L. Agassiz. 
L. Agassiz. 
A. Agassiz. 



NORTHERN COAST OF MAINE, GRAND MANAN, AND EASTPORT. 



Bolina alata Ag. W. Stimpson. 

Mert?ii*i<i ovum Moreh. A. Agassiz. 

Pleurobraclda rhododactyla Ag. W. Stimpson. 

Id i l'ia roseola Ag. W. Stimpson. 

Aurelia flavidula Per. et Les. W. Stimpson. 

Cyanea arctica Per. et Les. W. Stimpson. 

Manama auricula H. J. C. W. Stimpson. 

Lucernaria quadricornis Mull. W. Stimpson. 

Haliclystus auricula II. J. C. W. Stimpson. 

Haliclystus salpinx II. J. C. W. Stimpson. 

Oceania languida A. Ag. L. Agassiz. 

C/y/fl volubilis A. Ag. A. E. Verrill. 

Clytia bicopJwra Ag. W. Stimpson. 

Orthopyxis poterium Ag. A. E. Verrill. 

Eucope diaphana Ag. A. Agassiz 

Encope pyrifonnis A. Ag. J. E. Mills. 

Obelia commissuralis McCr. J. E. Mills. 

Laomedea amphora Ag. J. E. Mills. 
McUcertum campanula P. et Les. L. Agassiz. 

Staurophora laciniata Ag. W. Stimpson. 

Dynamena pumila Lamx. A. Agassiz. 

Diphasia fallax Ag. W. Stimpson. 

Sertularia abictina L. J. E. Mills. 

Sertularia cupressina L. W. Stimpson. 



Sertularia argentea L. J. E. Mills. 

Sertularia falcata Ag. W. Stimpson. 

Sertularia latiuscida Stimps. "W. Stimpson. 

Sertularia myriophyllum L. A. E. Verrill. 

Sertularia Jilicula Ell. & Sol. W. Stimpson. 

Sertularia producta Stimps. W. Stimpson. 

Amphitrocha ruc/osa Ag. W. Stimpson. 

Cotulina tricuspidata A. Ag. W. Stimpson. 

Cotulina poly zonias Ag. A. E. Verrill. 

Cotulina tamarisca A. Ag. W. Stimpson. 

Hali'cium halecinum Johnst. A. E. Verrill. 

Halecium muricatum Johnst. A. E. Verrill. 

Grammaria gracilis Stimps. W. Stimpson. 

Grammaria robusta Stimps. W. Stimpson. 

Acaulis primarius Stimps. W. Stimpson. 

Eudendrium dispar Ag. A. E. Verrill. 

Coryne mirabilis Ag. W. Stimpson. 

Clava leptostyla Ag. W. Stimpson. 

Candelabrum plirygium Bl. W. Stimpson. 

Corymorpha pendula Ag. W. Stimpson. 

Thamnocnidia tenella Ag. A. E. Verrill. 

Tulmlaria larynx Ellis. W. Stimpson. 

Tubularia Coutliouyi Ag. W. Stimpson. 

Hydractinia polyclina Ag. A. E. Verrill. 



NO. II. 



29 



226 



GEOGRAPHICAL DISTRIBUTION. 



NOVA SCOTIA. 



Bolina alata Ag. 
Plcurobrachia rhododactyla Ag. 
Idi/ia roseola Ag. 
Aurelia flav'uhda Per. et Les. 
Ci/anca arctica Per. et Les. 
IIa/icl//stus auricula II. J. C. 
Clijtia volubilis A. Ag. 
Clytia bicnphora Ag. 
Ortliopyxis potwium Ag. 
Laomcdca (rfi'cAotowia-like)i 
Laomedea (f/elatinosa-likc). 
Laomedea (gen ic j//a/-like) . 
Lafuea cornuta Lamx. 
Lafica dumosa Sars. 
Cosmetira sp. 



Anticosti Exp. 
Anticosti Exp. 
Anticosti Exp. 
Anticosti Exp. 
Anticosti Exp. 
Anticosti Exp. 
Anticosti Exp. 
Anticosti Exp. 
Anticosti Exp. 
Dawson. 
Dawson. 
Dawson. 
Anticosti Exp. 
Anticosti Exp. 
Anticosti Exp. 



Dynamcna pumila Lamx. 
Sertularia abietina L. 
Sertularia argentea L. 
Sertularia plumea Dawson. 
Sertularia falcata L. 
Sertularia myriopJii/llum L. 
Sertularia latiuscula Stimps. 
Cotulina tricuspidata A. Ag. 
Cotulina polyzonias Ag. 
Cotulina tamarisca A. Ag. 
Halecium yiuricatum Johnst. 
Thuiaria tliuja Flem. 
Eudcndrium (ramosm4ite) . 
Tubularia larynx Ellis. 
Tubularia Coulliouyi Ag. 



Dawson. 
Anticosti Exp. 
Dawson. 
Dawson. 
Anticosti Exp. 
Anticosti Exp. 
Dawson. 
Anticosti Exp. 
Anticosti Exp. 
Anticosti Exp. 
Anticosti Exp. 
Anticosti Exp. 
Dawson. 
Dawson. 
Dawson. 



Mertensia ovum Mb'rch. 
Plewobraclda rhododactyla Ag. 
Idyia cucumis Less. 
Jilf/ia borcalis Less. 
Aurelia flaridula Per. et Les. 
Cyanca arctica Per. et Les. 
Chrysaora hcpta'na Per. et Les. 
Trachyncma du/itale A. Ag. 
Afatiania auricula H. J. C. 
Lucernaria quadricornis Miill. 
Haliclystus auricula II. J. C. 
Medusa Inmorplia Fab. 
Tiaropsis diademata Ag. 
Campanularia volultilis JNIorch. 
Campanularia olivacea Lamx. 
Eucope diaphana Ag. 



GREENLAND. 

Fabricius. Zyyndactyla yrocnlandica P. et Les. Fabricins. 

Fabricius. Melicertum campanula Per. et Les. Fabricius. 

Fabricius. Dynamena pum'da Lamx. Fabricius. 

Scoresby. Sertularia abietina L. Fabricius. 

Fabricius. Sertularia argentea L. Fabricius. 

Fabricius. Amphitrocha rugosa Ag. Fabricius. 

INIartens. Cotulina polyzonias Ag. Fabricius. 

Fabricius. Halecium lialccinum Johnst. Fabricius. 

Fabricius. Bougainvillia supcrc'diaris Ag. JNIorch. 

Fabricius. Coryne mirabilis Ag. Sabine. 

Steenstrup. Coryne pusilla Giirt. INIorcli. 

Fabricius. Coryne muscoidcs Johnst. ]\Io'rch. 

Mb'rch. Candelabrum jrfirygium Bl. Fabricius. 

ISIbrch. Tubularia indivisa Linn. Morch. 

ISIorch. Hydractinia polydina Ag. Fabricius. 
Morch. 



SYSTEMATIC TABLE 

OF THE ORDERS AND FAMILIES OF NORTH AMERICAN ACALEPHJE 

DESCRIBED IN THIS VOLUME. 



Order CTENOPHOR.E Esch. 
Suborder LOBAT.E Esch. 

Family Bolinidae Ay. 
Family Ocyroeae Less. . 

Suborder SACCATE Ag. 

Family Mertensidae Ag. 
Family Cydippidae Gey. . 

Suborder EURYSTOM.E Leuck. 
Family Beroidae Esch. 

Order DISCOPHORJE EscJi. . 
Suborder RIHZOSTOME.E Ag. 

Family Rhizostomidas Esch. . 
Family Polyclonidae Ag. . 

Ag. 



Suborder 

Family Aureliada? Ag. 
Family Sthenoniae Ag. . 
Family Cyaneidae Ag. 
Family Pelagidae Gey. . 

Suborder HAPLOSTOME.E Ag. 
Family Thalassanthese Less. . 

Suborder TRACHYNEMID.E A. Ag. 

Family Trachynemidae Geg. . 
Family Leuckartidaa Ag. . 

Suborder LUCERXARI.E Johnst. 

Family Cleistocarpidae //. J. C. 
Family Eleutherocarpidae H. J. C. 



PAGE 

7 


Order IIYI 


14 


Suborder 


14 


Family 


25 


Family 


C\S* 


Family 


26 


Family 


26 


Family 


29 


Family 


35 


Family 


Q C 


Family 


oO 


Family 




Suborder 


40 


Family 


40 


Family 


A f\ 


Family 


40 


Family 


41 


Family 


41 


Family 


41 


Family 


43 


Family 


44 


Family 


47 


Family 




Suborder 


51 


Family 


51 


Suborder 


54 


Family 


f- * 


Suborder 


55 




60 


Family 




Family 


6fr 


Family 


61 


Suborder 


62 


Family 



PAGE 

)ROIDJE Johnst. ... 64 

SERTULARIJi Ag. . . 68 

Oceanidae Esch. . . .68 

Eucopidse Gcg. . . 81 

yEquoridaa Esch. . . .95 

Geryonopsidse Ag. . . 112 

Polyorchidae ,1. Ag. . .118 

Laodiceidse Ag. . . 121 

Melicertidae Ag. . . . 1 28 

Plumularidae Ag 139 

Sertulariadae Juhnst. . . 141 

TUBULARLY Ag. . . 149 

Nemopsidaj Ag. . . . 149 

Bougainvilleae Lutk. . 152 

Nucleiferse Less. . . .164 

Williade Furies . . 171 

Sarsiadaa Forbes . . .175 

Ortliocorynidae A. Ag. . 183 

Pennaridae McCr. . .186 

Tubulariadae Johnst. . 189 

Hydraidae Gray . . .197 

Ilydractinidas Ag. . . 198 

DIPHY.E Cuv. , . .199 

Diphyidae Esch. . . 199 

PHYSOPHOR.E Gold/. . . 200 

Agalmidaj Brandt . . 200 

PORPIT.E Gold/.. . . 214 

Physalidae Brandt . . 214 

Velellidaj Each. - . .216 

Porpitidae Guild. . . 218 

TABLTLAT/E Ag. . . .219 

Milleporidae Ag. . . 219 



INDEX OF GENERA AND SPECIES. 



[Synonymes are in Italics.] 



Acaulis STIMPS. . 

primarius STIMPS. . 
Acles LESS. .... 
Acrochordium MEY. . . . 
JEginopsis J. MULL. 
.ZEginopsis BR. 

Laurentii BR. 
.ZEquorea PER. et LES. . 

albida A. AGASS. 

ciliata ESCH. . 

globularis MORCH 

f/roenlandlca PER. et LES. 
Aglaophenia LAMX. . 

cristata McCR. 

franciscana A. AGASS. 

pi-lasgica McCR. 

trifida AGASS. 

trieuspis McCR. 
Aylaura penicillata BL. . 
Alcinoe LESS. .... 

vermicularis GOULD 
Alcyonium ecldnatum GOULD 
Amphitrocha AGASS. 

cincta AGASS. . 

rugosa AGASS. . 
Anais LESS. . 
Arethusa BROWN . 
Armenistarium COSTA . 
A tract i/l is WRIGHT 
Aurelia PER. et LES. 

aunt a GOULD 

flavidula PER. et LES. 

labiata CHAM, et EYS. 

marginalia AGASS. . 

sex-ovariis MORCII 

Beroe BROWN . 

cucullus MOD. 
cucumis FAB. . 
cucumis MERT. . 
glandiformis MERT. . 
ovata ESCH. 

ovum FAB. . . . 
pileus FAB. . 



PAGE 

151 

151 

218 

184 

51 

54 

54 

109 

110 

109 

103 

103 

139 

140 

140 

139 

140 

140 

119 

14 

15 

198 

146 

146 

146 

14 

214 

218 

122 

41 

42 

42 

43 

43 

42 

35 
26 
36 
34 
34 
35 
26 
30 



Beroe (continued) 

pileus SCOR. . 

punctata CHAM, et EYS. 
Biblis LESS. . 
Bolina MERT. 

alata AGASS. . 

liltoralis McCR. . 

microptera A. AGASS. 

septentrionalis AGASS. . 

septentrionalis MERT. 

vitrea AGASS. 
Bougainvillia LESS. 
Bougainvillia LESS. . 

Mertensii AGASS. . 

superciliaris AGASS. . 

Calamella OKEN 
Calicella HINCKS . 
Candelabrum BL. . 

plirygium BL. 
Campanella LESS. 
Campanella BL. 

campanula MoRCH . 

Fabricii LESS. 

pachyderma A. AGASS. 
Campanularia LAMX. 

dumosa JOHNST. 

dumosa LEIDY 

no! ifor mis McCR. 

syringa STIMPS. . 

volub'dis ALDER 

volubilis LEIDY . 
Campanulina VAN BEN. . 
Cassiopea TIL. 

frondosa ESCH. . 

Pallets PER. et LES. 
CepJiea rhizostoma GIBBES 
Chrysaora ESCH. 

helvola LESS. 

melanaster BR. 
Chrysomitra GEG. . 
Circe MERT. 

camtschatica BR. . 

digitalis MORCH 



PAGE 

26 

35 

41 

14 

15 

19 

19 

19 

14 

19 

155 

152 

152 

153 

159 

77 

186 

186 

130 

51 

130 

130 

52 

93 

126 

122 

80 

70 

77 

80 

122 

41 
41 

40 
48 
50 
50 
216 
55 
55 
57 



230 



INDEX OF GENERA AND SPECIES. 



Circe impatiens AGASS. . 
Clava GMELIN. 

leptostyla AGASS. 

multicornis STIMPS. . 

squamata MORCH 
Clavula WKIGHT 
Clauxtra LESS. 
Clytia LAMX. . 

bicophora AGASS. 

cylindrica AGASS. . 

cylindrica AGASS. 

intermedia AGASS. . 

volubilis A. AGASS. 
Corymorpha SARS 

nutans STIMPS. . 

pendula AGASS. 

pJtri/r/ia MoRCH . 
Coryne GART. 

mirabilis AGASS. . 

rosaria A. AGASS. . 
Corynitis McCR. 

Agassizii McCR. 
Cosmetira FORBES. 
Cosmetira up. 
Cotulina AGASS. . 

Greene! A. AGASS. . 

polyzonias AGASS. ' . 

tamarisca A. AGASS. 

tricuspidata A. AGASS. 
Crematostoma A. AGASS. 

flava A. AGASS. . 
Cucullus Q. & G. 
Cunina ESCII. 

octonarta McCR. 
Cyanea PER. et LES. . 

ambigua LESS. 

arctica PER. et LES. . 

ferruginea ESCH. 

fulva AGASS. 

Postelsii BR. . 

PosteMi GOULD . 

versicolor AGASS. . 
Cyaneopsis behringiana BR. . 
Cydalisia LESS. . 

punctata LESS. 
Cydippe Escir. . 

cucullus ESCH. 

cucumis LESS. . 

ovum ESCH. 

pileus GOULD . 
Cytceis SARS . 

Dactylometra AGASS. . 

quinquecirra AGASS. . 
Diancea DELLE CHIAJE . 
Diancea Q. & G. . 
Diancea LAMK. 



55 Diancea 

170 cyanella LAMK 47 

170 denticulata LAMK. . . . 47 

170 Diphasia AGASS. ..... 142 

. 198, corniculata AGASS.. . . 143. 

164 fallax AGASS 142 

41 rosacea AGASS. . . . 142 

77, 81 Diphyes Cuv 199 

78 pusilla McCR. . . . 199 

78 Dtylocraspedon BR 41 

80 Dipurena McCR 180 

77 cervicata McCR.. . . '.181 

77 conica A. AGASS. . . . 181 

192 strangiilata McCR. . . .181 

. 192 Dryodora AGASS. . . 34 

192 glandifbrmis AGASS. ... 34 

. 186 Dynamena LAMX 141 

175 cornifina McCR. . . .142 
. 175 pclastjica BL 139 

176 pumila LAMX 141 

. 183 Dysmorphosa PHIL. . . . 163 

183 fulgurans A. AGASS. . . . 163 
. 127 

128 Ectopleura AGASS. . . . 190 

. 146 turricula AGASS 191 

147 ochracea A. AGASS. . . 191 

. 146 Eirene ESCH 112, 113 

147 ccerulea AGASS. . . . 112 

. 146 digitate Escn 57 

108 gibbosa AGASS. . . . 112 

. 108 Epenthesis McCR. . . . .70 

199 folleata McCR. ... 70 

51 Ephyra PER. et LES 41 

51 octolabata GOULD . . . 42 

44 Ersrea ESCH 199 

43 EsehschoUzia LESS 34 

44 glandiformis LESS. ... 34 
47 Eucheilota McCR 74 

46 duodecimals A. AGASS. . . 75 

47 ventricularis McCR. . . 74 
44 Eucope ~GEG 83 

46 alternata A. AGASS. . . 86 

47 articulata A. AGASS. . . .89 
35 diaphana AGASS. ... 83 
35 diaphana AGASS. . . .86 

29 divaricata A. AGASS. . . 91 
26 fusiformis A. AGASS. ... 90 
26 parasitica A. AGASS. . . 87 
26 polygena A. AGASS. ... 86 

30 pyriformis A. AGASS. . . 88 
161 Eucoryne LEIDY . . . . .186 

elegans LEIDY . . . 187 

48 Eudendrium EHREXB. . . .159 
48 cingulatum STIMPS. . . 153 

113 dispar AGASS. . . . .159 

60 ramosum JOHNST. . . . 160 

47 ramosum McCR. . 16.0 



INDEX OF GENERA AND SPECIES. 



231 



Eudendrium (continued) 

tonne A. AGASS. 
Eudoxia ESCII. . 

alata McCR. . 
Euphysa FORBES 

virgulata A. AGASS. 
Enrybia ESCII. 
Eurybiopsis GEG. 
Eutima McCn. . 

limpida A. AGASS. . 

mira McCR. 

pyramidalis AGASS. 

variabilis McCR. . 
Evayora PER. et LES. 

Foveolia PER. et LES. 

octonaria A. AGASS. 

Gemmaria ]\IcCR. 

cladopliora A. AGASS. 

gemraosa McCR. . 
Geryonia ESCII. . 
Geryonopsis FORBES 
Globiceps AYRES 

tiarclla AYRES . 
Gonionemus A. AGASS. 

vertens A. AGASS. 
Grammaria STIMPS. 

gracilis STIMPS. . 

robusta STIMPS. 

Halecium OKEX. 

haleeinum JOIIXST. 

miiricatum JOIINST. 
Haliclystus II. J. CLARK 

auricula II. J. CLARK . 

salpinx II. J. CLARK 
Halimocyathus II. J. CLARK 

platypus H. J. CLARK . 
HalocJtaris AGASS. 

sjtiralis AGASS. 
Halopsis A. AGASS. . 

cruciata A. AGASS. 

ocellata A. AGASS. 
Heccsedecomma BR. . 

ambignnm BR. 
Hcrmia JOHXST. 
Ilippocrcne McCR. 
Hippocrene MERT. 

Bougainvillei BR. 

Bougainvttlei GOULD 

carolin M/S/X McCR. 

supcrciliaris AGASS. 
Hybocodon AGASS. . 

pvolifer AGASS. 
Hydra LINN. 

carnea AGASS. 



160 

199 

199 

189 

189 

60 

60 

116 

116 

116 

118 

116 

41 

51 
51 

184 

184 
184 
60 
112 
186 
187 
128 
128 
148 
148 
148 

147 

148 

147 

62 

62 

64 

61 

61 

183 

183 

99 

102 

99 

43 

43 

175 

155 

152 

152 

153 

156 

153 

193 

193 

197 

197 



Hydra (continued) 
gracilis AGASS. 
tennis AYRES 
squutnata FAB. 

Hydractinia VAX BEX. 
echinata LEIDY 
polyclina AGAS&. 

Idyia FLEM. . 

borealis LESS. 

cucumis LESS. 

cyathina A. AGASS. 

ovata LESS. 

roseola AGASS. . 
Idyopsis AGASS. . 

affinis AGASS. 

Clarkii AGASS. 

Janira OKEX 

cucumis LESS. 

Lafcea LAMX. 

calcarata A. AGASS. 

cornuta AGASS. . 

cornuta LAMX. 

dumosa SARS 
LaocUcea AGASS, 
Laodicea LESS. . 

calcarata A. AGASS. 

cellularia A. AGASS. 
Laomedea LAMX. . 

amphora AGASS. 

dicliotoma LEIDY 

divaricata McCR. 

gelatinosa LEIDY 

gelalinosa GOULD 

gigantea A. AGASS. 

pacifica A. AGASS. 

rigida A. AGASS. 
Lesueuria EDW. . 

hyboptera A. AGASS. 
Linuche ESCH. 
Liriope GEG. . 

scutigera McCR. . 

tenuirostris AGASS. . 
Lizzia FORBES . 

grata A. AGASS. 
Lucernaria MULL. 

auricula FAB. . 

auricula MULL. . 

Fabric ii AGASS. 

fascicularis FLEM. 

octoradiata LAMX. . 

phrygia FAB. 

quadricornis MULL. 

typica GREENE . 



197 
197 
198 
198 
198 
198 

35 
36 
36 
38 
35 
36 
39 
40 
39 

34 
34 

122 
122 
122 

126 

126 

122 

127 

122 

127 

93 

93 

91 

91 

88 

91 

94 

94 

93 

23 

23 

216 

60 

GO 

60 

161 

161 

62 

62 

63 

62 

62 

63 

186 

62 

62 



232 



INDEX OF GENERA AND SPECIES. 



Manania H. J. CLARK . 

auricula H. J. CLARK . 
Margelis STEENST. 

carolinensis AGASS. 
Medea ESCH. 

fulgens Escn. 
Medusa LINN. . 

cequorea FAB. 

aurita FAB. 

beroe LINN. . 

limorpha FAB. 

campanula FAB. . 

campanulatq Bosc . 

capillata FAB. 

digitalis FAB. . 

frondosa PALL. . 

labiata ESCH. . 

pelagia LINN. 
Melanaster AGASS. 

Mertensii AGASS. 
Melicerta PER. et LES. 

campanula PE'R. et LES. 
Melicertum ESCH. . . 
Melicertura OKEN 

campanula ESCH. . 

georgicum A. AGASS. . 

penicillata LESS. 

penicillatum ESCH. 
Mertensia GEG. . 
Mertensia LESS. . 

cucullus AGASS. 

glandiformis GEG. 

ovum Mtirch . 

Scoresbyi LESS. . 
Mesonema ccerulescens BR. 
Millepora LINN. . 

alcicornis LINN. 
Mnemia SARS 
Mnemiopsis AGASS. 

Garden! AGASS. . 

Leidyi A. AGASS. . 
Monocraspedon BR. 
Myriothela SARS 

Nanomia A. AGASS. . 

cara A. AGASS. 
Nemopsis AGASS. . . 

Bachei AGASS. . 

Gibbesi McCR. . . 

Obelia PER. et LES. . 

commissurab's McCR. . 
Oceania AUCT. . 
Oceania PER. et LES. . 

folleata AGASS. 

gregaria A. AGASS. 

languida A. AGASS. 



61 Oceania (continued') 

62 tubulosa GOULD . 

155 Ocyroe PER. et LES. . 

156 Ocyroe RANG 

35 labiata BL. 

36 maculata RANG . 
41 Orthopyxis AGASS. 

103 poterium AGASS.. 

42 

35 Parypha AGASS. 

98 cristata AGASS. . 

130 crocea AGASS. 

130 microcephala A. AGASS. 

44 Pelagia PER. et LES. 

57 americana PER. et LES. 

41 Brandtii AGASS. 

43 cyanella PER. et LES. . 

47 denticulata BR. 

50 denticulata PER. et LES. 

50 nocfiluca CHAM. 

130 quinquecirra DES. 

130 Pennaria GOLDF. . 
119 gibbosa AGASS. . 

130 tiarella McC'R. 

130 Persa McCR. . . 
135 incolorata McCR. . 

119 Phacellophora BR. . 
119 camtschatica BR. 

34 Phialidium LEUCK. 

26 Phortis McCR 

26 gibbosa McCR. . 

34 Physalia LAMX. 

26 Arethusa TIL. . 

26 aurigera McCR. 

108 pelasgica Bosc . 

219 Platypyxis AGASS. 

219 Platypyxis AGASS. . 

14 cylindrica AGASS. . 

19 Pleurobrachia FLEM. 

20 Bachei A. AGASS. . 
20 rhodddactyla AGASS. . 
41 Scoresbyi MORCH 

186 Plumularia LAMX.. 

Plumularia LAMX.. 
200 arborea DES. 

200 falcata JOHXST. 

149 franciscana TRASK 

149 gracilis MURR. 

149 myriophyllum JOHNST. . 

pelasgica LAMX. 

91 quadridens McCR. 

91 struthionides MURR. . 

164 Podocoryne SARS . 

70 Polybostricha BR. . 

70 helvola BR. . 

74 Polyltrachiona GUILD. 

70 linnceana GUILD. 



175 
41 
25 
43 
25 
81 
81 

194 

194 

195 

195 

47 

47 

48 

47 

48 

47 

47 

48 

186 

186 

187 

60 

60 

44 

44 

70 

112 

112 

214 

214 

214 

214 

77 

80 

80 

29 

34 

30 

30 

139 

140 

140 

144 

140 

145 

145 

139 

140 

140 

163 

50 

50 

218 

218 



INDEX OF GENERA AND SPECIES. 



233 



Polyclonia BE. . 

frondosa AGASS. 
Polyorchis A. AGASS. 

penicillata A. AGASS. 
Porpita LAMX. . 

atlantica LESS. 

linnaeana LESS. . 
Proboscidactyla BR. . 

flavicirrata BR. . 
Ptychogena A. AGASS. . 

lactea A. AGASS. 
Pyxidium LEUCK. 

Ratarin ESCH. 
Ratis LESS. 
Rhacostoma AGASS. 

atlanficum AGASS. . 
Rhegmatodes A. AGASS. . 

floridanus AGASS. . 

tennis A. AGASS. 
Rhizogeton AGASS. 

fusiformis AGASS. 
Rhizostoma ESCH. 

Saphenia FORRES . 

aplcata McCR. 
Sarsia LESS. . 

mirabUis AGASS.* . 

glacialis MORCH . 

turricuJa McCR. 
ScypJtistoma SARS . 
Sertularia Lixx. . 

abietina Lixx. 

anguina TRASK 

argentea ELL. et SOL. 

corniculata MURR. . 

cupressina Lixx. . 

faloata Lixx. . 

fall ax JOHXST. . 

fastigiata FAB. 

filicula ELL. et SOL. . 

furcata TRASK 

gracilis A. AGASS. 

Greenei MURR. 

Jialecina Lixx. 

labrata MURR. 

latiuscula STIMPS. 

muricata ELL. et SOL. 

myriophylhnn Lixx. , 

pelasgica Bosc 

pinnata GOULD . 

plumca DES. . 

polyzonias Lixx. . 

producta STIMPS. . 

pumila MORCH 

rosacea Lixx. . 

rugosa Lixx. 



41 Sertularia (continued) 

41 tamarisca Lixx. . . . .147 

119 tenerissima STIMPS. . . . 144 

119 thuja FAB 141 

218 thuja Lixx 148 

218 tricmpidata ALD. . . . 146 

218 tricuspidata MURR. . . . 147 

173 turgida TRASK .... 145 

173 SHicularia MEY 81 

137 Spadix GOSSE 186 

137 Staurophora BR 136 

194 laciniata AGASS 136 

Mertensi BR 137 

216 Sthenio Du.i 175 

218 Stipula SARS 175 

103 Stomolrachium FORBES . . . .130 

103 Stomobrachium BR. . . 98 

95 lenticular e GOULD ... 98 

97 tentaculatum AGASS. . . 98 

95 Stomolophus AGASS 40 

170 meleagris AGASS. ... 40 

170 Stomotoca AGASS. . . . 168 

41 apicata, AGASS. . . . 168 

atra AGASS. . . . .168 

168 "Strobila SARS . . . . . 41 

168 Syncoryna EHREXB 175 

175 SyndictyoiL-A. AGASS. . . . 177 

175 reticulaTum A. AGASS. . .177 

175 

191 Thamnocnidia AGASS. . . . 195 

41 spectabilis AGASS. . . .195 

143 tenella AGASS. . . . 195 

143 tubularoides A. AGASS. . .196 

144 Thaitmantias ESCH 70 

144 Thaumantiax GEG 127 

143 diaphana AGASS. ... 83 

143 Thoa LAMX 147, 159 

144 dispar AGASS. . . . 159 
142 Thuiaria FLEM 148 

144 thuja FLEM 148 

145 Tiaropsis AGASS 69 

145 diademata AGASS. ... 69 

145 Tima ESCH 113 

147 forraosa AGASS. . . . 113 

148 Trachynema GEG 55 

144 camtschaticum A. AGASS. . 55 

145 digitale A. AGASS. . . .57 
147 TrncTtopyxis AGASS 77 

145 Tubularia Lixx. .... 196 
139 Couthouyi AGASS. . . . 196 

146 crislata McCR 194 

142 iiitliciaa GOULD . . . 196 

146 larynx ELLIS .... 196 

145 ramosa GUILD. . . . 153 

141 stellifera COUTH 175 

142 Turris LESS 164 

146 digitalis MORCH .... 57 



234 



INDEX OF GENERA AND SPECIES. 



Turris (continued) 

vesicaria A. AGASS. 
Turritopsis McCR. 

nutricula McCR. . 
Velella LAMX. 

mutica Bosc 

soptentrionalis ESCH. 

Willia FORBES . 

ornata McCR. . 



164 
1G7 
167 
216 
216 
217 

171 
171 



Wriyhtia AGASS. . 

Zanclea McCR. . 

gemmosa McCR. . 
Zygodactyla BR. . 

coerulescens BR. . 

crassa A. AGASS. . 

cyanea AGASS. . 

groerilandica AGASS. 



70 

184 

184 
103 
108 
106 
107 
103 



THE END. 



Cambridge : Electrotyped and Printed by Welch, Bigelow, & Co. 





- r. v 



- .,, 




, -^ 







*.- *.'