322 MEDUSA OF THE WORLD. 



Octogonade mediterranea Zoja. 

 Octogonade mediterranea, Zoja, 1896, Bolletino Scientif. Pavia, anno 17, p. 101, 1 tav., 6 fig. 



Bell somewhat higher than a hemisphere, with bulging sides and thick walls; evenly 

 rounded, without an apical projection. 60 to 70 mm. wide. 16 tentacles with hollow, tapering 

 basal bulbs, shorter than the bell-radius, and numerous small, tapering, rudimentary tentacle- 

 bulbs (150 or more). 50 to 60 large, marginal lithocysts, each containing 12 to 20 concretions, 

 and a large ocellus. Apparently these marginal sense-organs are similar in structure to those 

 of Tiaropsis. These lithocyst-sacs are somewhat irregularly placed between the tentacles. 

 Velum well developed. 8 slender, straight radial-canals and a ring-canal. Manubrium 

 short, tubular, with 8 radial-canals extending from the sides of the stomach nearly to the 

 circular vessel. Color of entoderm pale white. Found at Messina, Italy, February to March. 

 (See fig. 180. J 



Genus STOMOBRACHIUM Brandt, 1835. 



Stomobrachium, Brandt, 1835, Mem. Acad. Imperiale des Sci. St. Petersbourg, Sci. Nat., ser. 6, tome 2, p. 220; Ibid., 1838, 

 tome 4, p. 358. — Gould, 1841, Report Invertebrata Massachusetts, p. 349. — Lesson, 1843, Hist. Zooph. Acal., p. 315. — 

 Agassiz, L., 1862, Cont. Nat. Hist. U.S., vol. 4, p. 361. — Agassiz, A., 1865, North Amer. Acal., p. 98. 



Stomobrachium + Staurobrachium, Haeckel, 1879, Syst. der Medusen, pp. 223, 224. 



The type species is Stomobrachium lenttculare Brandt, from the Falkland Islands. 



GENERIC CHARACTERS. 



/Equoridae with 8 or more simple, unbranched canals which arise separately and at equal 

 intervals from the margin of the stomach. With 4 lips. With numerous tentacles and mar- 

 ginal lithocysts. Development unknown. 



This genus is distinguished from Mquorea by having but 4 lips, and from Halopsis by 

 the fact that its radial-canals arise separately, not in clusters from the periphery of the stomach. 

 Haeckel would institute a new genus, Staurobrachium, for medusae resembling Brandt's 

 Stomobrachium, but with 16 or more radial-canals, while according to Haeckel's system 

 Stomobrachium is restricted to include only medusae with 12 radial-canals. A broader defini- 

 tion seems desirable, for there is no place in Haeckel's system for medusae which may possibly 

 be discovered with less than 12, or with 13 to 15, radial-canals, and considering the extreme 

 variability in numbers of these structures in .^quoridae, it is important that we should define 

 our genera so as to include a considerable range in number in the radial-canals. 



Stomobrachium lenticulare Brandt. 



Stomobrachium lenticulare, Brandt, 1835, Recueil Actes Sci. publiques Acad. Imp. Sci. St. Petersbourg, p. 20 (of the "separate''); 

 1838, Mem. Acad. Imperiale des Sci. St. Petersbourg, Sci. Nat., ser. 6, tome 4, p. 358, taf. 3, fign. 6, 7.— Agassiz, L., 

 1862, Cont. Nat. Hist. U. S., vol. 4, p. 361.— Haeckel, 1879, Syst. der Medusen, p. 224.— Bedot, 1905, Revue Suisse de 

 Zool., tome 13, p. 148 (literature to 1850). 



Stomobrachium lenticularis, Lesson, 1843, Hist. Zooph. Acal., p. 315. 



(??) Stomobrachium tentaculatutn, Agassiz, A., 1865, North Amer. Acalephae, p. 98, figs. 140-142. 



Bell flat, hour-glass-shaped, about 30 to 40 mm. wide, and 10 to 12 mm. high. 150 to 200 

 short tentacles. 12 radial-canals. The stomach is a small, flat sack, and there are 5 to 6 

 small triangular lips, with thin edges slightly folded. There are 12 linear, cylindrical gonads 

 upon the mid-regions of the radial-canals. This species is found off the Falkland Islands, 

 South Atlantic coast of South America. 



Stomobrachium tentaculatutn Agassiz, from Massachusetts Bay, Atlantic coast of America, 

 is very closely related to, if not identical with, this species. Brandt's medusa has not been seen 

 since he described it. 



Stomobrachium tentaculatum L. Agassiz. 



(?) Medusa bimorpha, Fabricius, 1780, Fauna groenlandica, No. 356. 



Stomobrachium lenticulare, Gould, 1841 (non Brandt), Report Invert. Anim. Mass., p. 349. 



Stomobrachium tentaculatum, Agassiz, L., 1862, Cont. Nat. Hist. U. S., vol. 4, p. 361.— Agassiz, A., 1865, North Amer. Acal., 



p. 98, figs. 140-142.— Haeckel, 1879, Syst. der Medusen, p. 224, — HaRgitt, 1904, Bull. U. S. Bureau of Fisheries, vol. 



24, p. 51. 



