L.M.B.C. MEDUSA. 375 



fully expanded, are about twice the length of the umbrella. 

 The umbrella of the smallest specimen taken measured 

 4 mm. in length and 3 mm. in width : the largest 

 specimen 9 mm. long and 6 mm. wide. Other specimens 

 measured — 6 mm. long and 6 mm. wide ; 6 mm. long and 

 7 mm. wide ; 8 mm. long and 8 mm. wide. 



Sarsia pidchella may be an early stage of S. tuhulosa. 



Distribution. — Shetland, St. Andrews, Plymouth, Firth 

 of Clyde. 



Sarsia tuhulosa, Sars, (9). 



Byeiiey (6) records this species. — " Caught in the 

 Mersey, rare, Mr. Price." Haddon (14) records S. 

 tuhulosa in Dublin Bay. 



I have taken in Port Erin Bay several specimens of 

 young Sarsia, but have not been able to determine for 

 certain the species. 



Dipurena halterata, (Forbes 15). 

 Slahheria halterata, Forbes (.9). 



Two ^^ecimens taken in August, 1892. One measured 

 25- mm. in length and 2 mm. in width. Manubrium 

 extended to 8 mm. Tentacles 2 mm. long. No repro- 

 ductive organs present. The medusa may easily be 

 distinguished by the large knob, containing nematocysts, 

 at the free end of each of the four tentacles. 



Distribution. — Jersey, Mount's Bay (Cornwall), Ply- 

 mouth. 



Steenstrupia ruhra, Forbes (9). 



Steenstrupia galanthus, Hseckel {15). 

 Steenstrupia flaveola, Forbes {9). 

 Forbes describes and figures the above species, the 

 former taken off the Shetlands, the latter at Penzance. 

 They mainly differ in colour. Hseckel regards them as 



