Chap. VI. TABULAR VIEW. 151 



R. capeusis Less. — Cephea capensis Q. and G. Zool. Uran. ; Cephee 

 Guerin, PI. 84, fig. 9. — Cephea capensis Fsch. — Cape of Good 

 Hope (Quoy and Gaimard). As in the figure of Quoy and 

 Gaimard, the umbrella is too much closed to allow the base 

 of the arms to be seen, I am doubtful whether this is a 

 genuine Rhizostoma. 



A renewed study of these species, based, as far as possible, 

 upon direct comparisons, is necessary to make it certain that 

 they are truly distinct; though their geograjjhical distribution 

 renders it already probable. A comparison of the handsome 

 figures published by Milne-Edwards and Gosse, of the Rhizos- 

 tomejB of the Mediterranean and of the Bi'itish Channel, shows 

 diflferences which, if not specific, have not yet been noticed 

 as belonging to the cj^cle of development of one and the 

 same species. Whether the two species described from the 

 Red Sea differ one from the other, I am unable to say ; nor is 

 the assertion of Ehrenberg, that one of them is identical with 

 Rhizostoma Cuvieri, to be considered as settling its affinity, 

 as he himself states he never saw well preserved sjiecimens. 

 Claustra Mertensii Less. — Cyanea? Brandt, PI. 31, — is unquestion- 

 ably a genuine Rhizostoma; but we have no information 

 upon its origin and its specific characters. 



Stomolophus Agass. See p. 138. Differs chiefly from Rhizostoma 

 by the great length of the upper bunches of the marginal 

 lobes of the arms, and the peculiar form of the lower ones. 

 St. Meleagris Ac/. — Atlantic Ocean, coast of Georgia (L. Agassiz). 



Stylonectes Ag. — Orythia Q. and G. (p. p.). — Rhizostoma Esch. (p. p.). 

 The fate of the genus Ephyra admonishes one to be 

 extremely cautious in distinguishing genera among Acalephs, 

 and I would, therefore, suggest that the Orythia lutea Q. and 

 G. may be a young Rhizostoma Pulmo, respecting the embry- 

 ology of which nothing, whatever, is known at present. But 

 if it is an adult Medusa, then its peculiar actinostome, with 

 eight connate arms, each ending in a long tricuspidate stylet, 

 and the small bunch of marginal fringes at their base, show 

 it to constitute a distinct genus. 

 St. luteus Ag. — Orythia lutea Q. and G., Ann. Sc. Nat. 1827, vol. 

 X. PI. 4, B, fig. 1. — Rhizostoma lutea Esch. — Rhizostoma lutea 

 Less. — Mediterranean: Straits of Gibraltar (Quoy and Gaimard). 



