L98 



MEDl'S.E OF THi; WOULD. 



Genus THAUMANTIAS Eschscholtz, 1829. 



Tliaumiintia* (in part), EsciisnioLTZ, 1829, Svst. der Acal., p. 102. OKEN, 1835, Allgemeine Naturgesch., Bd. 5, p. 226. 

 LESSON, 1843, Hist. Zooph. Acal., p. 176. FORBES, 1848, British Naked-eyed Medusa, p. 45, etc. 



Thaumaniia!. GI.C.KNBAUR, 1856, Zcit. fiir wissen. Zool., Bd. 8, p. 237. WRK;HT, 1862, Quart. Journ. Microscop. Sci., N. S., 

 vol. 2, pp. 221, 308. HINCKS, 1868, British Hydroid Zoophytes, p. 178. BROWNE, 1896, Proc. Zool. Soc. London, 

 pp. 480, 489. HARTLAI B, 1905, Zoologische Jahrbucher, Supplement 6, p. 567. 



Ten ii'iniiii 4 ThaumantieiSf HAECKEL, 1879, Syst. der Medusen, pp. 125, 127. 



Halmomises, VON KENNEL, 1891, Sitzbcr. Nat. Ges. Dorpat, Bd. 9, p. 282. 



The oldest species is "Thaumantias hemispheerica" Eschscholtz, 1829 = Medusa In-nu- 

 sfi/i.rru-a Gronovius, 1760; but Browne, 1896, shows that this is undoubtedly a Phialidium, 

 and has lithocysts which former observers had overlooked. "Thaumantias aeronaut ica" 

 Forbes, 1848, is probably a Pliinlitiiuni, and the type species appears to be Thaumantias 

 fdlularia Haeckel = LaoJicc ccllularia A. Agassiz, 1862, 1865. 



GENERIC CHARACTERS. 



Thaumantiadae with 4 gonads upon the 4 radial-canals. With 4 or more tentacles. 

 Manubrium without a peduncle and with 4 simple lips. No marginal sense-clubs or cirri. 

 The hydroid is Thaumantias. 



Haeckel, 1879, would restrict Thaumantias to include medusae with 16 or more tentacles, 

 and he proposed a new genus Tetrancma for medusae with 4 tentacles. We adopt a broader 

 definition and restore the older interpretation of Forbes and others, and include medusae 

 with 4 or more tentacles under Thaumantias. 



T/iaumantias is separated from Laodicea by the fact that there are no marginal sense- 

 clubs or cirri in Thaumantias, whereas these structures exist in Laodicea. 



The hydroid of Thaumantias was first described by Wright, 1862 (Journ. Microscopical 

 Science, vol. 2, p. 221). The stem is simple (or branched?) and rooted by a thread-like 

 stolon; hydrothecae campanulate; polypites with a prominent funnel-shaped proboscis. 

 The stem is sometimes ringed throughout, sometimes only at the base and summit. The 

 calycles of the polypites are denticulate, the edge having about 7 teeth. There are 16 or 

 more tentacles in a single ring. Wright reared the hydroid from the eggs of Thaumantias 

 inconspicua Forbes. 



Thaumantias is unfortunately a receptacle for all the medusae of Phialidium in which 

 lithocysts have not been observed. The older authors, previous to Gegenbaur's researches 

 published in 1856, generally failed to observe the lithocysts; hence our heritage of numerous 

 "species" of "Thaumantias." Browne, a most assiduous student of European medusae, 

 recently stated that he had never found a Thaumantias. I have never taken one in thousands 

 of surface-tows made along the Atlantic coast of the United States from Eastport, Maine, to 

 Tortugas, Florida, nor did I find a single specimen of Thaumantias in cruising over the 



Pacific while serving as assistant to Dr. Alexander 

 Agassiz. Dr. Lobianco, however, kindly permitted 

 me to study some well-preserved specimens of a 

 medusa collected by him at Naples, which I believe 

 to be a Thaumantias. 



Thaumantias eschscholtzii Haeckel. 



Thaumantias esrlischoltzii, HAECKEL, 1879, Syst. der Medusen, p. 129, 

 taf. 8, fig. 4. LEVINSEN, 1893, Vid. Meddel. Nat. Foran., 

 Kjbbenhavn, ser. 5, Bd. 4, p. 145. 



Bell flat and watch-glass-shaped, and 3 to 4 

 times as broad as high. About 10 to 12 mm. in 

 diameter. There are 240 to 280 slender tentacles 

 with globular basal bulbs which are provided with 

 ocelli. The tentacles are about half as long as the 

 radius of the bell. There are no sense-clubs or 

 cirri upon the bell-margin. The velum is well 

 developed. There are 4 straight, narrow radial- 



rii,. 102. Thaumantias esrlischoltzii, after 



Harcki-l, 1879. 



