. The Danish Ingolf-expedition. Marine animals -- Arctic regions; Scientific expeditions; Arctic regions. Fig. 55. Stephanaiige nexilh. Transverse section of tentacle. or sterile. Because of the strong development of the gonads, filling up almost the whole cavity of the body, I have not been able to find any acontia, in the maceration preparations of the. Fig. 56. Slephanauge nexilis. Section of a directive mesentery in the lower part of the actinopharynx. base of the mesenteries I have observed large nematocysts of very different length ()(5)//, which perhaps belonged to acon
. The Danish Ingolf-expedition. Marine animals -- Arctic regions; Scientific expeditions; Arctic regions. Fig. 55. Stephanaiige nexilh. Transverse section of tentacle. or sterile. Because of the strong development of the gonads, filling up almost the whole cavity of the body, I have not been able to find any acontia, in the maceration preparations of the. Fig. 56. Slephanauge nexilis. Section of a directive mesentery in the lower part of the actinopharynx. base of the mesenteries I have observed large nematocysts of very different length ()(5)//, which perhaps belonged to acontia as there were no such neniatocvsts in the filaments. Verrili. 1922 ]). 99 mentions, however, that acontia are present, but apparently few. He has drawn a figure (0 Fl. 22) of this species wdth 4 ejected acontia. As far as I can see the figure represents this species. As all specimens examined by me concerning the arrangement of the mesenteries had two pairs of directives symmetrically arranged, the species probably does not ])ropagate asexually. The nematocysts were usuallv rather ()|)aciue but I think that the nematocvsts marked as microliasic y>-mastigoj)hors are such. Remarks: Verrili. in 1922 described the sj)pcies in detail but in several points incorrectly. The tentacles are about twice as many than \'krrill states. The cinclides are ])resent onlv in the directive chambers, not scattered. The figure 6 PI. 22, certainlv a magnification of fig. 5 PI. 6 in the paper of 1883 (Blake-ex])ed.), showing threads representing ejected acontia, is probably in- correct, as it gives an idea of scattered cinclides. The ])erfect pairs of mesenteries are only 6, not 12 or more as \'errill states. His figured sections PI. 28 figs. 3, 4, PL 30 fig. 3, 1922, are sections through the oral disc, not through the actinopharynx. Also the first cycle of mesenteries are fertile, in op]iosition to Verrill's statement. Stephanauge acanellae (\'err.). Saijarlia acanellae n. sp. Verrill 1883-85
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Keywords: ., bookcentury1800, bookdecade1890, booksu, booksubjectarcticregions
