Bulletin of the Bureau of Fisheries . i/, North American Acalephse, 1865, p. 1-. Haeckel, System der Medusen, 1879, p. 55 i Umbrella flat and disk like, Bomewhat arched above; margin normally 8-lobed and with 8 rhopa-lia which are symmetrically disposed in the sinuses of marginal lobes. Marginal tentacles numerous,but short, forming a delicate fringeabout the entire margin except at themarginal sinuses. Radial canals hi,of three sorts—perradial and inter-radial, each of these branching andanastomosing freely, and adradial, 8 innumber, simple and unbranched, pass-ing directly from the gastric p
Bulletin of the Bureau of Fisheries . i/, North American Acalephse, 1865, p. 1-. Haeckel, System der Medusen, 1879, p. 55 i Umbrella flat and disk like, Bomewhat arched above; margin normally 8-lobed and with 8 rhopa-lia which are symmetrically disposed in the sinuses of marginal lobes. Marginal tentacles numerous,but short, forming a delicate fringeabout the entire margin except at themarginal sinuses. Radial canals hi,of three sorts—perradial and inter-radial, each of these branching andanastomosing freely, and adradial, 8 innumber, simple and unbranched, pass-ing directly from the gastric pouchesto the marginal canal. Manubriumquadrate, with oral arms about as longas the bell-radius, rather broad and heavy proximallv, but terminating in , .-,,•„•_,, * - ? Scyphostomae of Aureha flavidula. slender pointed crenulated ends; en-tire margins of arms more or le>s folded or scalloped and richly supplied with nematocysts. In life the oral arms are carried in an extended position, much as shown in the plate. Gonads. 68 BULLETIN OF THE BUREAU OF FISHERIES. crescent-shaped organs, located upon the floor of the gastric pouches and giving the medusa a dis-tinctive appearance not easily confused with any of the Scyphomedusae likely to be found within theregion. Amelia exhibits interesting aspects of variability, particularly in the radial canal system, the mar-ginal lobes, rhopalia, and gonads. Browne (1901) has shown this in some detail in A. aarita. Anexamination of several hundred specimens of adult Aurelia flavidula shows a very similar condition, aratio of variation as high as 20 to 25 per cent, and an examination of more than a thousand of theephyrse of this medusa gives a like result. Details upon this point will he given in another contributiondealing specifically with this feature. Colors. — A rather dull-colored medusa, the umbrella being almost transparent with pale yellowishpink, slightly more noticeable in the region of the gonads, which share in the
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectfisheries, bookyear19
