. Text-fig. 29. Physalia physalis. End branchlet of a mature gonodendron shown in section in PI. XXIV, fig. 3. The plane of section is indicated by a line. Two gonophores that lie on the underside and appear in the plate are not shown in the drawing, g = gonophore, jp = jelly-polyp, nect = nectophore, p = palpon. Prior to the work of Steche, Huxley (1851, 1859), Haeckel (1888), Brooks and Conklin (1891) and Goto (1897) all regarded the gonophores as male organs. Huxley and Haeckel thought that the ova developed later on the stalked 'female medusoids' (now known to be nectophores) after becomin
. Text-fig. 29. Physalia physalis. End branchlet of a mature gonodendron shown in section in PI. XXIV, fig. 3. The plane of section is indicated by a line. Two gonophores that lie on the underside and appear in the plate are not shown in the drawing, g = gonophore, jp = jelly-polyp, nect = nectophore, p = palpon. Prior to the work of Steche, Huxley (1851, 1859), Haeckel (1888), Brooks and Conklin (1891) and Goto (1897) all regarded the gonophores as male organs. Huxley and Haeckel thought that the ova developed later on the stalked 'female medusoids' (now known to be nectophores) after becoming freed from the gonodendra. Richter (1907) also regarded the gonophores as being male organs and his whole account of their development is most unusual, as he himself admitted, and is in my view unacceptable. In fact I think that Richter reversed the proper sequence of events in the various growth-stages. Steche (1907) demonstrated for the first time the existence in Physalia of two kinds of gonophores, female as well as male, and stated that each gonodendron was wholly of one sex only. Even now Steche's work is not well known, and this is the first occasion on which his observations have been confirmed. Curiously enough Steche himself stumbled quite accidentally across the fact that some of the gonophores were female, when he was investigating the ' Glockenkern' (entocodon) of various hydroids and siphonophores during the winter of 1905. In some sections of the nectophore of Physalia he had fortunately included a large specimen of the real female gonophore growing from its base. He recorded how surprised he was to find a single layer of unripe germ-cells instead of the thick spermarium he had expected to see. He described and figured in longitudinal section a developmental phase in some ovoid medusoids, in which the spadix of giant ' multinucleate' cells was capped by a single layer of what he called female germ-cells (Taf. X, fig. 26). I have a section which confirms his fig
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