S'lKPHioNKoN — The Genus Coralliinorphvs. 181 



cycle is incomplete. Text-fig. 1 i.s a \\\a\) of the teiitacle-anaiigenicnt of the 

 large specimen. Actual )iropoiti(inK arc not meant li> be rcjiresentecl in it. 

 The marginal tentacles are shown in dutline, the others as circles, and the 

 main mesenteries are shown as single lines radiating from the actinopharynx. 

 It will he noticed that where 4th cycle tentacles appear at the margin they 

 come one on each side of a 3rd cycle tentacle, and that ord cycle disc- 

 tentacles do not occur over the endocoel of any iJrd cycle marginal tentacle 

 which has not yet attained its 4th cycle neighbours. 



Internal slrv.ctvir. — There are 21 pairs of laige mesenteries whieli join the 

 actinopharynx. They include 2 pairs of apparent directives, and 10 lateral 

 pairs on one side, 9 on the other. This and all subsequent anatomy applies 

 to the large specimen ; the small one I did not dissect. There are smaller 

 mesenteries, apart from the 21 main pairs, probably occurring in all sectors 

 where 4th cycle tentacles are found. 1 confirmed their existence in 2 sectors, 

 but did not wish to damage the specimen enough to do so in all ; however, 

 they doubtless exist. I could not exactly determine their extent, nor can I 

 say much about the other mesenteries, because the internal preservation is 

 not good, and more could not be ascertained without complete destruction of 

 the specimen. The large mesenteries fill up the coelenteron, and are 

 thick and much twisted and complicated in places. They have a most curious 

 appearance in sections. The endoderm is thick, the mesogloea variable— it 

 is typically thick and curiously lobed in outline where the mesentery leaves 

 the body-wall, then very thin and irregular, and twisted up in the middle 

 part of the mesentery, and thick again close to the actinopharynx, at the 

 level taken by my sections. The part of a mesentery where it joins the wall 

 is shown in I'l. XX, fig. 2, which includes the lobed and thickened part of 

 the mesogloea, and also the beginning of the thin part, and shows the general 

 look of the endoderm. The body-wall is at the bottom end of the figure. 

 Fig. 4 shows simply the mesogloea from another mesentery, anil only the 

 pare adjacent to the body-wall, as a less lobed example. The musculature of 

 the mesenteries is merely a feeble fringe, hardly visible in the ligure, and not 

 forming processes, as iu most anemones. The directives arc slmrlcr and 

 thicker throughout than most of the others. 



There is no perceptible dillerentiation of siphonoglyphcs. The mesen- 

 terial filaments in my sections are simple (PI. XX, fig. 1), but they have at 

 the proximal side, on either side of the stem, a concentration of nuclei wliich 

 rather suggests the forerunner of a ciliated lobe. There is no sphincter. The 

 musculature in the ectoderm of disc and tentacles is weak, but better 

 developed than elsewhere in the body, sometimes even rising into siiort 



