u 



U 



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 



