MEDUSA. I. .„ 

 49 



land; Liitkeii (1875, p. 188) who was not aware of the mistake, induded Mclicertiim cavipanula in 

 his list of the medusae of Greenland, and from the authority of Liitken it was likewise included in 

 the lists published by Winther (1880, p. 274) and Fewkes (1888b). 



Haeckel (1879, p. 136) was the first to see the mistake, and he sharply criticises Agassiz, 

 because he referred the American 8-rayed medusa to Melicertutii campiinida (Fabricius), Eschscholtz, 

 Oken, as also because he referred Ocea7iia ocfocostata vSars to Meliccrljwt piisillum Eschscholtz. 

 Haeckel is of opinion, however, that the generic name Melicertiim Agassiz, non Oken and Esch- 

 scholtz. ought to be retained for the species campaimla and georgictt7n^ because "Agassiz wirklicli 

 die erste gute Beschreibung und Abbildung . . . gegeben und die acht Radial-Caniile als Familie- 

 Character hervorgehoben hat". 



The European form, on the other hand, is elevated by Haeckel to be the type of a new- 

 genus, Melicerfidim//, on account of the presumed presence of ''niarginale Kolben (oder Cirren)" (op. 

 cit. p. 137). As a matter of fact, Haeckel himself has not seen this medusa, but his meditations 

 are based on the previous descriptions and, obviously, mainh' on the figures of Ehrenberg. These 

 figures exhibit a series of short tentacles alternating with the long ones, but on account of the way in 

 which these short tentacles were drawn by Ehrenberg, Haeckel got the apprehension that they 

 were clubs. — After Haeckel (1879) the European form has, mostly, been recorded as Mclicertidiuiii 

 octocostatiDir, also Hartlaub (1894, p. 192) uses that name at the same time as he states that the 

 medusa has no marginal bulbs but small tentacles as numerous as the common tentacle.s, and that 

 this is not a sufficient reason for a generic distinction between the American and the European species. 



A review of the generic names, which in the course of time have been applied to these spe- 

 cies, will give us the following list: Oceania^ ^Eqiiorca^ Stomobrachiutn^ Melicerttim a.nA Meh'cfrtidiuiii. 

 When we want to state, which of those names ought to be used as the correct one, we may at once 

 release the three first, as they are now used for medusae belonging to quite different groups. Thus 

 remains the choice between the two last-mentioned names. 



Browne (1905, pp. 764 — 767) has di.scussed this question. After a record of the history of the 

 eenus and a demonstration of the identit\- of Mclicertinn and Mclicertidiuiii the author states as fol- 

 lows: "After due deliberation, I think it would be the best to retain and amend the genus Melicer- 

 tidiiim, and to do away with the genus Mclicertinn. To retain the latter genus would only lead to 

 more confusion, as it is clear that Meliccria or Mclicertinn of Oken is not the same genus as Afeli- 

 ccrtiiiii of Agassiz. It is really a new genus, with a new t\pe species" (p. 766). 



Mayer (1910), on the contrary, prefers the generic name Melicerlum for the following reason: 

 "... it appears that Ehrenberg, 1837, placed Sars's species in the genus Melicerttiui, and I think 

 it should remain there and be considered a cotype of that genus" (op. cit. p. 207). 



Mayer's vindication .seems to me to be objectionable, because Eh re n berg's use of the name 

 of Melicertitiii for that medusa was simply due to an erroneous identification. Ehrenberg did not 

 refer his specimens to the species described by Sars (he has, probably, not seen vSars's description), 

 but he identified them erroneously with Melicerlum campaiinlatiun E.schscholtz. 



Something may account for the view of Browne to release tlie equivocal generic name Meli- 

 certum, but the use of the name Melicertidiiini seems to me to be precarious, because this genus was 



The Ingolf-Expedition. V. 8. ' 



