Jørgensen 1905 - Drymyomma elegans

This species, when fully developed, is very easily recognized by its branched byspines on the outside shell. The outside shell is strongly developed, thick walled, diameter ± 85µ. The pores are roundish with broad intermediate walls, unevenly developed, though not so much so as in Chromyechinus borealis, on an average about the same size or perhaps most of them little smaller. The two inner shells seem in all important respects to answer to those of the following species, Chromyechinus borealis. Still, I must call attention to the fact that I have had very little chance of examining them more thoroughly, as the species occurs so sparsely. The number of the main spines seems to vary (?) from about 15 up to about 20. The largest are beautifully developed, long, slender and always branchless, a few of the smaller ones seem, on the contrary, occasionally to have a single needle shaped side branch, like the corresponding one in Chromyechinus borealis. Of byspines there are some resembling the main spines, only smaller and especially narrower. From these 3-edged spines there seems to be every transition to numerous narrow needle shaped ones without distinct edges. Most of the byspines, especially the narrow ones, carry in their upper halves from 1-4 obliquely diverging narrow branches, some of these again carrying a similar, but shorter, side branch. There seems to be a regular transition from the more delicate radial spines to the more strongly developed, 3-edged and branchless, byspines. It is, however, as above mentioned, probably not quite certain that the previously mentioned Echinomma-forms with long, slender main spines and byspines, should all be included in this species. These forms occur, with us, much more frequently than the fully developed Drymyomma elegans. Rare and scarce, only found at a few places in 1899: Sea off Gaukværö, 19/1, 0-700 m., Senja, 21/1, 0-130 m., the Vest Fiord, 1/2, 0-200 m., Skorven, 4/2, 350-300 m., the Tys Fiord I, 28/3, 0-700 m.

Distribution: Very rare also on the west coast of Norway, only in deep water. Also known from the Norwegian Ocean off Sundmøre and from the Vest Fiord, Feb. 1901 (Cfr. Gran L. 70, p. 150-151).

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