. Discovery reports. Discovery (Ship); Scientific expeditions; Ocean; Antarctica; Falkland Islands. 356 DISCOVERY REPORTS GONOPHORES (Pis. XX-XXIV, Text-fig. 29) Two of those who in the past have done the most detailed work on the gonodendra are Richter (1907) and Steche (1907). By one of those strange but not infrequent coincidences, these two men appear to have been working simultaneously but unknown to each other, the one at Leipzig and the other at Text-fig. 29. Physalia physalis. End branchlet of a mature gonodendron shown in section in PI. XXIV, fig. 3. The plane of section
. Discovery reports. Discovery (Ship); Scientific expeditions; Ocean; Antarctica; Falkland Islands. 356 DISCOVERY REPORTS GONOPHORES (Pis. XX-XXIV, Text-fig. 29) Two of those who in the past have done the most detailed work on the gonodendra are Richter (1907) and Steche (1907). By one of those strange but not infrequent coincidences, these two men appear to have been working simultaneously but unknown to each other, the one at Leipzig and the other at 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 lar
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