. The Danish Ingolf-Expedition. Scientific expeditions; Arctic Ocean. Iceland: Tistil fjord, 66°43' N., i4°53' W., — 78 — Ritchie (1912 p. 226) refers this species to Cladocarpus, but with a query, as he did not find gonangia in his specimens. These agree entirely with the present colonies (fig. XXXVI) which, from the comparatively short, broad hydrothecse, can hardly be confused with other species from northern waters. The col- onies in question show that the species should be placed under Halicornaria. The gonangia occur in several stages of development, but none fully developed. The series
. The Danish Ingolf-Expedition. Scientific expeditions; Arctic Ocean. Iceland: Tistil fjord, 66°43' N., i4°53' W., — 78 — Ritchie (1912 p. 226) refers this species to Cladocarpus, but with a query, as he did not find gonangia in his specimens. These agree entirely with the present colonies (fig. XXXVI) which, from the comparatively short, broad hydrothecse, can hardly be confused with other species from northern waters. The col- onies in question show that the species should be placed under Halicornaria. The gonangia occur in several stages of development, but none fully developed. The series of phases represented in the colonies investigated are entirely parallel to what we find in Cladocarpus integer (G. O. Sars); the oldest stage also seems to show that it developes, as does the species mentioned, an "upper lip" which will dome out more or less over the opening; further investigations must determine, how far the development proceeds. Phylactogonia are altogether lacking in the colonies here concerned, and the species must consequently be regarded as a Halicornaria; there is, however, the possibility that it may later prove to be a primitive Cladocarpus. The otherwise close resemblance of the species to Cladocarpus integer would also seem to point in the same direction; the last-named species has hitherto likewise been regarded as a Halicornaria^ but, as is further explained below, it is as a matter of fact a primitive Cladocarpus, whose phylactogonia do not always or everywhere attain development. We cannot therefore altogether disregard the possibility that Halicornaria campanulata may also under normal conditions develope more or less regularly- occurring phylactogonia. But as long as this has not been shown to be the case, the species must remain in the genus Halicornaria. Ritchie {1912 p. 227) could not state the locality of origin of the species nearer than "from the neighbourhood of Iceland", which from a bio-geographical point of
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