TRACHYMEDUS.E — GONIONEMUS. 343 



Bigelow, 1909, has examined more of the so-called "species" of Gomoncmus than has 

 any other student of the medusae. He concludes that the species fall under two groups: 



(1) The suvaensis, pelagicus, and hornelli group with gonads restricted to only a fraction 

 ot the lengths of the radial-canals and with 16 lithocysts; and (2) the vertens, agassvzii, 

 depressum, and murbachu group with gonads upon nearly the entire lengths ot the radial- 

 canals, and with numerous lithocysts. 



Bigelow concludes that there is but one species in group 1 and this should be called G. 

 suvaensis. He also finds that the differences between G. vertens and G. murbachu, although 

 slight, are apparently constant, consisting in the higher bell and more slender tentacles of 

 G. vertens. 



Gonionemus vertens A. Agassiz. 



Goriionemus vertens, Agassiz, A., 1862, Cont. Nat. Hist.U. S., vol.4, P*35°> '865, North Amer. Acal., p. 128, figs. 197-201. — 

 Mureach and Shearer, 1903, Proc. Zool. Soc. London, vol. 2, p. 183. — Bigelow, H. B., 1909, Mem. Mus. Comp. 

 Zool. at Harvard College, vol.37, p. 106. 



Gonynema vertens, Haeckel, 1879, Syst. der Medusen, p. 147. 



Bell 17.5 mm. high, 15 mm. wide, with thin walls. About 60 to 70 tentacles, twice as 

 long as bell-diameter. A large oval, bulb-like swelling upon bell-margin below the insertions 

 of each of the tentacles. The tentacles are ringed with helical ridges of nematocysts and are 

 thick and heavy in appearance. Each tentacle has a well-developed, aboral, adhesive pad 

 near its outer end, beyond which the tentacle suddenly bends at a right angle with its main 

 shaft. The lithocysts are external and alternate with the tentacles in position. The manu- 

 brium is well developed, so that the mouth is at the level of the velar opening. The lips are 

 fringed. There are 4 sinuously reflected gonads on the 4 radial-canals. Gonads deep red, 

 radial-canals deep brown, bell yellowish-green. 



Puget Sound, Gulf of Georgia, British Columbia, and Washington, Pacific coast of 

 North America. 



The habits of this medusa appear to be similar to those of G. murbachii. It is found 

 among the kelp near the shores in July. 



This species is distinguished by its high bell, long slender tentacles, and deep-red gonads. 

 It appears to be locally abundant. 



Gonionemus murbachii Mayer. 



Plate 45, figs. 1 to 4; plate 46, figs. I to 3. 



Gonionemus, sp., Murrach, 1895, Journal Morphol., Boston, vol. 11, p. 493. 



Gonionemus vertens, Hargitt, 1897, Zool. Bulletin, Boston, vol. I, p. 27, 5 figs, (regeneration); 1899, Biol. Bulletin Woods 

 Hole, vol. 1, p. 41, figs. 7-20 (grafting and regeneration); Goriionemus, sp., 1900, Science, N. S.,vol. 12, p'. 341 (varia- 

 tions); 1901, Biol. Bulletin Woods Hole, vol. 2, p. 233, figs. 8-14, plates 1-4, 46 figs, (variations of the medusa); 

 Gonionemus murbachii, 1901, American Naturalist, vol. 35, p. 593, fig. 60; Gonionema, 1902, Biol. Bulletin Woods Hole, 

 vol. 4, p. 1, 1 1 figs, (regeneration); Gonionemus murbachii, 1904, Bull. U. S. Bureau of Fisheries for 1904, vol. 24, p. c;^. 

 plate 6, fig. la. — Morgan, 1899, American Nat., vol. 33, p. 939, 12 figs, (regeneration); 1907, Regeneration by Morgan, 

 translated into German by M. Moszkowski, Leipzig, p. 195, fig. 55 a-d. 



Gonionemus, Loeb, 1900, American Journ. Phvsiol., vol. 3, pp. 383-396; 1905, Studies in General Physiology, Chicago, pp. 553, 

 559> 754 (effects of ions); 1906, Journal Biol. Chemistry, New York, vol. I, p. 431 (effects of magnesium); 1906, Dynamics 

 of Living Matter, Columbia Univ. Biol. Series, No. 8, p. 81. — Perkins, 1901, Biol. Bulletin Woods Hole, vol. 2, p. 363, 

 2 figs, (order of growth of tentacles). 



Gonionema murbachii, 1902, Johns Hopkins University Circ, vol. 21, p. 87, 1 1 figs, (development); 1902, Biol. Bulletin Woods 

 Hole, vol. 3, p. 172, 7 figs, (degeneration phenomena in the larvae); 1903 Proc. Acad. Nat. Sci. Philadelphia, vol. C4, 

 p. 750, 21 figs., plates 31-34 (development). 



Gonionema vertens, Nutting, 1901, Bull. U. S. Fish Commission, p. 3S2, fig. 103. 



Gonionemus murbachii, Mayer, 1901, Sci. Bulletin Brooklyn Inst. Museum, vol. I, No. I, p. 5; 1906, Carnegie Institution of 

 Washington Publication No. 47, p. 43. — Yerkes, 1902, American Journal Physiologv, vol. 6, p. 434; Ibid., vol. 7, p. 181; 

 1904, Biol. Bulletin Woods Hole, vol. 6, pp. 84, 324 (reactions to stimuli); 1906, Journal Comp. Neurology and Physiol., 

 vol. 16, No. 6, p. 457 (reactions and behavior). — Murbach, 1903, Amer. Journal Physiol., vol. 10, p. 201 (static func- 

 tion); 1903, Science, ser. 2, vol. 17, p. 192; 1907, Biol. Bulletin, vol. 14, p. 11 (concretions entodermal, reactions to light). — 

 Bigelow, H. B., 1907, Bulletin Museum Comp. Zool. at Harvard College, vol. 48, p. 287, plates I-S (nuclear cycle, early 

 development).— Jennings, 1906, Behavior of the Lower Organisms, Columbia University Biol, series, vol. 10, pp. 192, 

 211, 214,219,221, 227, 230, figs. 118-120 (behavior and reactions to stimuli). — Morse, 1906, Journal Comp. Neurol, 

 and Physiol., vol. 16, No. 6, p. 450 (behavior and reactions to stimuli); 1907, American Naturalist, vol. 41, p. 683. 



Gonionema murbachii, Yerkes and Ayers, 1903, American Journal Physiol., vol. 9, p. 279, 2 figs, (reactions to stimuli).— 

 Hyde, 1902, Biol. Bulletin Woods Hole, vol. 4, p. 40, 3 figs, (histology and anatomy of nervous systems). 



Gonionemus, Maccallum, 1907, Journ. Biol. Chemistry, New York, vol. 2, No. 4, p. 385 (citation of Loeb's researches). 



