HYDROMED.USAE 



283 



Rathkea octopunctata belongs to the northern parts of the Atlantic and the Pacific 

 and has also been recorded from the Mediterranean and the Black Sea. R. formosissima 

 has up to now only been found at the Falkland Islands. 



Table showing the characteristics of all the specimens taken in 1898 



Genus Bougainvillia Lesson (1836) 



Syn. Hippocrene Mertens, 1835 (preoccupied). 

 Margelis Steenstrup, 1850. 



Generic characters. Margelidae with four perradial clusters of marginal tentacles, 



all of one kind and similar in structure. With four perradial oral tentacles, placed at 



some distance above the mouth rim, dichotomously branched, with terminal clusters of 



nematocysts. 



3-z 



