536 



MEDUSA OF THE WORLD. 



Haliclystus antarcticus Pfe£Fer. 

 Haliclyslus aniarcticui, Pkiffer, 1889, Mitthcil. Naturhist. Museum Hamburg, Jahrg. 6, p. 16. 



Bell flat, 17 mm. wide to bases and 27.5 mm. wide to ends ot arms. llei{;lit 1 1.5 mm. to 

 subumbrella disk and 15 mm. to ends ot arms. The stalk is 8 mm. long, flexible, and when 

 expanded it is about two-thirds as long as bell-height. It has 4 interradial, longitudinal 

 muscles and is 4-sided in cross-section, the longitudinal muscles being in the 4 flat or grooved 

 sides. The attached end of the stalk is swollen. There are 8 adradial arms 45° apart with 

 the 8 clefts all ot etjual depth, and each arm has more than 100 tentacles; 8 large biscuit- 

 shaped, marginal anchors about as long as width of stalk; 8 wide, lancet-shaped gonads, 

 widely separated one from another and extending to ends of arms. The number of sacs in 

 the gonads is not clearly defined in Pfeffer's specimens, but there appear to be at least 100 to 

 150 in 6 to 8 longitudinal rows. Stalk single-chambered thus illustrating the close relation- 

 ship between Holulystus and Lucirnaria. 



The medusa is a beautiful blue-violet in color, with lighter, somewhat reddish anchors 

 and tentacles. Found at South Georgia, Antarctic Ocean. 



Haliclystus kerguelensis Vanhoffen. 

 Haliclyitus kergueUnsisy Vanhoffen, 1908, Deutsche SiiJpolar-Expedition, 1901-190^, BJ. 10, Zool. 2, p. 31, taf. 2, fig. I. 



Bell 27 mm. wide across the outstretched arms exclusive of the tentacles, and 10 mm. 

 high. Arms 45^ apart, the concavities between them all similar each to each as in H. aiittirc- 

 ticus. Peduncle prismatic, 20 mm. long and 3 mm. wide. Not quite 50 tentacles in each 

 adradial cluster. Marginal anchors only one-third as wide as the peduncle in its expanded 

 state. 8 wide, lancet-shaped gonads. 



Fig. 340. — Haliclyitus stejnegeriy after Kishinouye, in Proc. U. S. Nat. Mus. 



Fig. 341. — Haliclystus kerguelensis^ after Vanhoffen in Deutsch. Sudpolar Expedition. 



Bell and peduncle sandy-brown with a play of green over the surface. Gonads dark 

 olive-brown and plainly visible through the walls of the lighter colored bell. Terminal knobs 

 of the tentacles rose-red. 



Found at Observatory Bay, Kerguelen Island, Antarctic Ocean; in July, growing on 

 the stems of Macrocystis. 



This form is closely related to H. (iiitarilii-us, but has fewer tentacles, smaller anchors, 

 and apparently a longer peduncle, although the stalk of H. tiiiturtticus was probably con- 

 tracted in Pfeffer's preserved specimens. There are also color differences between the two 

 forms. 



Genus HALIMOCYATHUS Clark, 1863. 



Halimocyalhus, Clark, 1863, Journ. Boston Soc. Nat. Hist., vol. 7, p. 536. — AoAssiz, A., 1865, North Amer. Acal., p. f>i. 



Halicyathus, Haeckf.l, 1880, Syst. der Mcduscn, p. 393. 



Manania, Clark, 1863, Journ. Boston Soc. Nat. Hist., Tol. 7, p. 541. 



The type species of this genus is H. platypus Clark, from Massachusetts Bay. 



