1896.] BRITISH HXDBOIDS AND MEDUSA. 473 



Part U.— MBDUS^> WITHOUT OE WITH UNKNOWN 

 HTDEOID FOEMS. 



These Medusae are arranged according to Haeckel's ' System der 

 Medusen.' 



ANTHOMEDUS^. 



Earn. CoDONiDTE. , 



DiruuENA UALTBBATA (Forbes). 



Slahheria halterata, Forbes (1848); Cocks (1849). 



Dijpurena halterata, Haeckel (1879); Browne (1895). 



I have occasionally met ■with one or two specimens of this 

 interesting medusa. 



I saw one specimen at Plymouth on 25th September, 1893. 

 The specimen was unfortunately in a bad condition, the umbrella 

 being turned inside out. The basal bulbs of the tentacles were of 

 a dark brown colour with a single deep crimson ocellus. At the 

 free end of each of the four tentacles there was a very large knob- 

 like cluster of nematocysts, and the upper half contained a dark 

 brown pigment. 



A single specimen was taken at Valencia on 10th April, 1895. 

 Umbrella about 1 mm. in length. 



Forbes describes and figures the gonads as slight swellings upon 

 the radial canals. This statement requires confirmation. Haeckel, 

 however, has taken a specimen at Jersey, which corresponded to 

 Forbes's dpscri])tion, except that the gonads were upon tlie 

 manubrium. Haeckel describes three swellings on the manubrium, 

 one above the other, filled with sperm, the lowest swelling reaching 

 nearly down to the mouth. 



Distribution. Jersey, Haeckel. 



England — Plymouth, E. T. B. Falmouth, Goclcs. Mounts Bay, 

 Forbes. Isle of Man, Broiune. 



Ireland — Valencia Island, E. T. B. 



DiPUEENA, sp.? (Plate XVI. fig. 2.) 



During my visit to Plymouth in September, 1895, 1 obtained 

 upon the 10th two specimens of a medusa which certainly belongs 

 to the genus Dipurena. I regard them as early stages on account 

 of medusa-buds being present upon the stomach. I have already 

 shown in the cases of Amphicodon friiiUaria, Margellium octo- 

 punctatmn, and Lizzin bloiidina, that it is a characteristic feature of 

 the young stages to bud oS medusae, and in the adult stage to have 

 gonads upon the stomach. I believe that Codonium gemmifenim and 

 Saj-sia proUfera, now regarded as distinct species, will be ultimately 

 proved to be only early stages of other known species. 



X have not yet been able to trace these early stages of Dipurena 



