L.M.B.C. MEDUSA. 395 



umbrella 4 mm. in diameter. About 15 tentacles in each 

 group, the outside ones being very small and evidently 

 growing. 



The compound tentacle-bulbs are curved, but not so 

 much as in the adult. The upper portion of the bulb 

 contains a dark brown pigment and from this mass 

 longitudinal bands extend towards each tentacle. A black 

 ocellus at the base of each tentacle. The oral tentacles 

 with about 16 branches. Generative products not present. 

 This is evidently a young specimen. It may be difficult 

 to distinguish the early stages of M. principis from those 

 of M. ramosa. There is a specimen of M. principis in the 

 museum of the Mar. Biol. Assoc, at Plymouth. Romanes 

 {18) has taken specimens in Cromarty Firth (= Bou- 

 gainvillea allma)ii et fruticosa, Romanes). 



Margelis hritannica, (Forbes 9). 



Bougainvillea hritannica, Forbes (9). 

 Margelis ramosa, Hseckel {15). 



Forbes first discovered and described this medusa in 

 1841, from specimens taken off Bute. Since then it has 

 been recorded from many places along our coasts. Clubb 

 {7) found specimens in Port Erin Bay during August, 1885. 



The umbrella is about as long as wide, 4 to 6 mm. 

 Four perradial groups of tentacles with 8 to 16 tentacles 

 in each group. The tentacles are united at the base and 

 form a compound tentacle-bulb. Near the base of each 

 tentacle there is a conspicuous ocellus. The oral tentacles 

 are usually three times dichotomously divided, and each 

 of the eight terminal branches ends in a cluster of 

 nematocysts. 



During May, 1893, I collected many specimens in Port 

 Erin Bay. The compound tentacle-bulbs are yellowish, 

 and the tentacles, when expanded, about twice the diameter 



