. The Danish Ingolf-expedition. Marine animals -- Arctic regions; Scientific expeditions; Arctic regions. 36 MEDUSA. I. Ptychogena antarctica Browne (1907, more thoroughly described in 1910, p. 29) is distinguished from Ptychogena lactea by the fact that the gonadial lateral folds are shorter and not attached to the subumbrella, and by the colour, the base of the tentacles being, according to Browne, provided with red entodermal pigment; according to Vanhoffen (1912), who has refound the species in the material from the German South-Polar expedition, the organs are dark coffee-brown. There is
. The Danish Ingolf-expedition. Marine animals -- Arctic regions; Scientific expeditions; Arctic regions. 36 MEDUSA. I. Ptychogena antarctica Browne (1907, more thoroughly described in 1910, p. 29) is distinguished from Ptychogena lactea by the fact that the gonadial lateral folds are shorter and not attached to the subumbrella, and by the colour, the base of the tentacles being, according to Browne, provided with red entodermal pigment; according to Vanhoffen (1912), who has refound the species in the material from the German South-Polar expedition, the organs are dark coffee-brown. There is one cordylus be- tween every successive pair of tentacles, and in some of these cordyli Browne found nematocysts (see p. 4).. Chart III. Occurrence of Ptychogena lactea A. Agassiz in the northern Atlantic and adjacent arctic waters. denotes the southern limit of the occurrence in the Barei^ts Sea, according to Linko. The hatching Vanhoffen (1912, p. 366) describes another species, Ptychogetia aiirea^ from four small speci- mens with about 32 tentacles and gold-yellow gonads with mature sexual products. Cordyli are not present. I am not convinced that this medusa belongs to the genus Ptychogena^ but I will not deny the possibility. I have had at my disposal for examination 12 specimens of Ptychogena lactea from 9 different localities. In the following list I have also included some non-preserved specimens from Godthaab Fjord, Greenland, found by the "Tjalfe" expedition; in the journal of the expedition they are shortly but clearly described, so much so thai they may be identified with complete Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Danish Ingolf-Expedition (1895-1896); Københavns universitet. Zoologisk museum. Copenhagen H. Hagerup
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Keywords: ., bookcentury1800, bookdecade1890, booksu, booksubjectarcticregions
