L.M.B.C. MEDUSA. 267 



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 allmani et fruticosa, Eomanes). 



Margelis britannica, (Forbes 9). 



Bougainvillea britannica, 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 



