. The Danish Ingolf-Expedition. Scientific expeditions; Arctic Ocean. 58 ANNELIDS. I. have to deal with small specimens that the difficulties commence; these are well known to every zoolo- gist who has had to deal with a considerable material of the genus in question. Even 0rsted himself writes in his Amiulatorum Danicorum conspectus p. 31. "Difficillimum stepe est eharacteres specificos firmos inter species hujus genesis statuere" and Levi use 11 completely gave up as to the northern forms, and united them all in one species, Ph. maculata L. As to the differences between Phyllodoce
. The Danish Ingolf-Expedition. Scientific expeditions; Arctic Ocean. 58 ANNELIDS. I. have to deal with small specimens that the difficulties commence; these are well known to every zoolo- gist who has had to deal with a considerable material of the genus in question. Even 0rsted himself writes in his Amiulatorum Danicorum conspectus p. 31. "Difficillimum stepe est eharacteres specificos firmos inter species hujus genesis statuere" and Levi use 11 completely gave up as to the northern forms, and united them all in one species, Ph. maculata L. As to the differences between Phyllodoce groenlandica 0rsted and Ph. maculata L. I shall first emphasize that, while Ph. maculata is a small or at any rate rather small species which only reaches a length of a few centimetres, the Phyllodoce groenlandica is a large species, probably the largest northern species, reaching a length of nearly half a meter. Orsted indicates in his description a maximum measure of 10 to 11 Danish inches. The largest specimen at my disposal measures 450 mm. in length, and several others reach a length of 400 mm. The colour of these animals is commonly greyish brown, so that the body itself is almost grey with a bluish hue, while the elytra are slightly chocolate-brown or earth-brown. In single specimens the body itself is dark brown, and the colour of the scales paler. In others the body is bluish, and in such specimens I have seen the dorsal leaves very dark, almost black. In the species under consideration the cephalic lobe is relatively smaller than in Phyllodoce maculata; it is somewhat broader in shape and the nuchal flabs more prominent; the dorsal cirri in Phyllodoce groenlandica are almost rectangular in shape, with the angles rounded, in Ph. maculata they are broadly ovoid terminating in a blunt tip. The ventral cirri in Ph. groenlandica end in a tip, in Ph. maculata the same are ovoid and do not terminate in a tip. In giving prominence to these differences I shall note that the ci
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