1896.] BBITISH HTDKOIDS AND MEDUBjE. 487 



Mitrocomella polydiademd (Romanes) is veiy much like Euchiloia- 

 pilosella to the naked eye ; but it has sixteen marginal vesicles 

 and no cirri upon the ex-uinbrella. 



BiSTBiBUTioN. Scotland — Shetland Islands, Forbes. 



England — Plymouth, Garstang, Allen. Falmouth, Alder. 



Ireland — Valencia Island, E. T. B. 



Epbhthesis ctmbaloidea, Haeckel, 



This is another mysterious medusa which has been banded down 

 to us by the ancient naturalists. Slabber first described it under the 

 name of Medusa cymhcdoidea in 1775, and Shaw (1789) has copied 

 Slabber's figures and also changed the name to Medusa campanella. 

 To judge from the figures given, the medusa appears to be very 

 much like Thaumantias hemisphcerica (Gronovius) with fewer 

 tentacles. The generative organs occupy the outer half of the 

 radial canals. The medusa was caught by Slabber in the act of 

 swallowing a fish, tail foremost, of which a figure is given. 

 Latiiarck (1817) has copied Slabber's description, and Eschscholtz 

 (1829) changed the generic name to Thaumantias. 



Blainville (1834) has given again Slabber's account of the species 

 and copied his figures, but has left out the wonderful fish. 



Haeckel (1879) has placed all these references under the name 

 of Epenihesis ei/mbaloidea, a genus of the Eucopid8B,and characterized 

 by the possession of 16 marginal vesicles and 16 tentacles. 



Amongst the synonyms Haeckel has placed Thaumantias 

 ihmnpsoni, Eorbes, which is also given as a doubtful synonym of 

 Tliaumantias forbesii, Haeckel (Thaumantidte, Haeckel). The 

 figure of Slabber's medusa bears no resemblance to Forbes's species, 

 which is more like Phialidium buslcianum (Gosse). It only requires 

 the addition of the necessary marginal vesicles to make the identi- 

 fication complete. These llaeckel has added. 



Eucope (jemmir/era, Keferstein (1862), is also given as a synonym 

 by Haeckel of Epenihesis cymbaJoidea. According to Keferstein 

 this medusa has a ciliated medusa-bud upon the stomach. I 

 prefer for the present to regard this medusa as a distinct species. 

 The medusa-bud is not described in detail and the figure shows 

 the external shape only. It may be a young stage of the parasitic 

 Ualcampa, which often attaches itself to the stomach or the 

 generative organs of medusae. 



Epenihesis cymbaloidea, Haeckel, and its synonyms have no 

 connection whatever with Phialidium cymbaloideum (Van Beneden). 



PiiiALiniuM TAEiABiLE, Haeckel. 



Under this name Haeckel has united several species which I 

 consider to be quite distinct. He gives no less than 26 references 

 which are divided into two sets, one for the Mediterranean and 

 the other for the Atlantic Ocean. 



Just as in the case of Thaumantias hem'.'phcerica, the early 

 writers omitted the marginal vesicles, which amongst the EuconideB 



