Medusae of the world . , each loop being composed of a narrow vessel,extending outward from the edge of the stomach on one side of a tentacle and then down onthe same side of a peronium, then along a quadrant of the margin, to ascend along the side ofanother peronium and to reenter the stomach on the adjacent side of a tentacle 900 away fromits place of origin. The gonads are developed in the ectoderm of the subumbrella wall of thestomach around the peripheral parts of the stomach-pouches. The entoderm of the stomach and its pouches are citron-yellow or rose-red. ManyTrachymedusae and Narcomed
Medusae of the world . , each loop being composed of a narrow vessel,extending outward from the edge of the stomach on one side of a tentacle and then down onthe same side of a peronium, then along a quadrant of the margin, to ascend along the side ofanother peronium and to reenter the stomach on the adjacent side of a tentacle 900 away fromits place of origin. The gonads are developed in the ectoderm of the subumbrella wall of thestomach around the peripheral parts of the stomach-pouches. The entoderm of the stomach and its pouches are citron-yellow or rose-red. ManyTrachymedusae and Narcomedusae are greenish by reflected, and red by transmitted, light andthis may account for the differing descriptions of its in the tropical Pacific. Vanhoffen, 1908 (Narcomedusen der Valdivia Expedition, p. 48, taf. 1 and 3),records thecapture of 19 specimens of an ALgma in the tropical Atlantic and Indian Oceans betweendepths of 2,000 fathoms and the surface. He calls this medusa Angina rosea, but it lacks the. Fig. 299.—Mgina citrea, after Eschscholtz, 1829. 452 MEDUSA OF THE WORLD. secondary clefts of the stomach-pouches and there are about ioo sense-clubs. Moreover 14of VanhofFens specimens had 5, and only 4 had 4 tentacles and peronial strands. The ten-tacles and stomach are pink or rose-red. Mouth a round opening. The marginal canal-system is well developed. This medusa was most abundant at depths between 1,000 and 2,000fathoms. Vanhoffen maintains that ALgina rosea is specifically distinct from AL. citrea, and certainlyhis observations recorded above appear to give substantial support to his contention, but inview of our imperfect knowledge of the development and range of variability of the species ofALgina I prefer to suspend judgment upon the point.
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectcnidari, bookyear1910
