Bulletin of the Bureau of Fisheries . x sans Vertebres, 2d edition, 1840, p. , Oceanic Hydrozoa, 1859, p. 100. Physalia arethusa L. Agassiz, Contributions to Natural History of the UnitedStates, 1862, p. 335. Chun, Die Siphonophoren der Plankton-Expedi-tion, 1897, p. 89. This is, for several reasons, the best known of large size and conspicuous float, ami long and numerous ten-tacles with their powerful batteries of nematocysts, have combinedto render the species noteworthy. These alone are generally sufficient for its easy identification. The large and beautifully c
Bulletin of the Bureau of Fisheries . x sans Vertebres, 2d edition, 1840, p. , Oceanic Hydrozoa, 1859, p. 100. Physalia arethusa L. Agassiz, Contributions to Natural History of the UnitedStates, 1862, p. 335. Chun, Die Siphonophoren der Plankton-Expedi-tion, 1897, p. 89. This is, for several reasons, the best known of large size and conspicuous float, ami long and numerous ten-tacles with their powerful batteries of nematocysts, have combinedto render the species noteworthy. These alone are generally sufficient for its easy identification. The large and beautifully colored pneumatophore, capable of niceadjustments to wind and wave, the graceful and pendulus tentacles, the languid, passively floatinghabit of the creature, and last, if not least, its venomous repute, render its presence a center of eagerinterest to observers. It is a fairly familiar object in Vineyard Sound and adjacent , at timesas many as fifty specimens being taken during a single cruise within a few miles of Woods Spll&roncc/cs yrarilis. After Mayer. THE SCYPHOMEDUSiE. In general form, structure, habits, and distribution the Seyphomedusa^ havemuch in common with the Hydromedusa> and probably sustain a much closerrelation to them than to any other of the ctelenterate classes. As a rule they are oflarger size, somewhat sluggish in habits, the margin of the umbrella is more or lessevidently lobed, and there is usually a large manubrium which is provided with largeoral lobes, often complexly fimbriated or plaited. The body is also usually muchthicker and more rigid than in the Hydromeduspe, and in some of the orders it isprovided with a well-organized muscular system. As in the Hydromedusa? there is usually a well-detined alternation of genera-tions, though with notable exceptions in some of the orders, and in all there seemsto be atendency toward the suppression of the nonsexual stage, which is frequentlyquite inconspicuous and more or less temporary. In co
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectfisheries, bookyear19
