156 DISCOPHOR^. Part III. 



Cephea to PI. 30. This glaring mistake has been copied by 

 all subsequent writers, and this circumstance seems to indi- 

 cate that no one of them has taken the trouble of reading 

 the text. We find it reproduced in Per. and LeS., who 

 first distinguished the genus Cephea. Their diagnosis of 

 Cephea cyclophora is drawn up from PL 29, but the name 

 Medusa Cephea, and the description on page 208, are referred 

 to among the synonyms; while the Cephea rhizostomoidea 

 is drawn iip from PI. 30, and the name Medusa octostyla 

 Forsk., and the description on page 206 referred to. And 

 this runs through the works of Lamarck, DeBlainville, Esch- 

 scholtz, Lesson, &c. It is very surprising that the name 

 Medusa octostyla should not have excited the attention of 

 compilers, and especially that of such observers as are quoted 

 above. It is true, Forskal's drawing is in so far inaccurate 

 as to represent nine instead of eight cirrhi, and these append- 

 ages are not mentioned in his text; but in Medusa Cephea 

 he says distinctly, fila plmima. Taking my acquaintance of 

 other Rhizostomidas as a guide to interpret the descriptions 

 and figures of Forskal, I do not hesitate to express my con- 

 viction that the two species of the celebrated Scandinavian 

 traveller belong to two distinct genera. 



Cephea Ptr. and Xe/S'. 



C. octostyla Ag. (non Esch., non Less.). — Medusa octostyla ForsJc, 

 Descr. An., PI. 29. — Cephea cyclophora Per. and LeS., Link., 

 DeBl, Esch., Less, (exlus. synon.), Milne-Edw. in Cuvier's Regne 

 An., PI. 51, fig. 4 (figure copied from ForsJcal; the same in 

 Encycl. M%i\i.). — Red Sea (Forskal). 

 C. ocellata Per. and LeS., LmJc., Esch., DeBl, Less. — Medusa ocel- 

 lata Mod. — Origin unknown. 



Polyrhiza Agass. 



Polyrhiza Cephea Ag. — Medusa Cephea ForsJc, Descr. An., PI. 30. 



— Cephea octostyla Esch., Less, (exclus. synon.). — Cephea 

 rhizostomoidea Per. and LeS., Lmk., DeBlainv. (exclus. synon.). 



— Red Sea (Forskal). 



P. fusca Ag. — Cephea fusca Per. and LeS., Lmk., Esch., DeBl. — 

 New Holland, DeWiWs Land (Peron and LeSueur). 



P. vesiculosa Ag. — Cephea vesiculosa Hemp, and Ehrenh , Akal. des 

 roth. Meeres. — Red Sea (Hemprich and Ehrenberg). 



