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 

 Strassburg. 



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 

 figure (PI. XXIV, fig. 3). Text-fig. 29 shows the plane in which the section was cut. 



Richter wrote an addendum to his paper in which he commented on Steche's work published while 

 his own manuscript was in the printer's hands. Most of the addendum is concerned with relatively 

 unimportant differences in their two papers, but Richter also remarked that ' Steche made some very 



