The collection of Echinoderms brought home by the Danmark- 

 Expedition , though it contains no new species or upon the 

 whole any great number of species, is, however, of considerable 

 interest in several respects. 



Through the researches of later years, among which those 

 carried out by Mr. James Grieg take a very prominent part, it 

 has been proved that several of those Echinoderms which were 

 hitherto recorded as occurring in the whole of the northern Atlantic, 

 are not really so widely distributed, the specimens from the cold 

 region of the Northern Sea being different from those inhabiting 

 the warm area, specifically or as varieties only, but distinct enough, 

 so that they should not be confounded as one and the same species, 

 inhabiting both the cold and the warm region. For this question 

 the present collection of Echinoderms is of considerable value. 

 Further it has given rise to additional knowledge of several spe- 

 cies—especially the rich material of Hathrometra (Antedon) prolixa 

 proved of great importance; the closer examination of these speci- 

 mens revealed the fact that their Pentacrinoid-larvæ are attached 

 to the cirri of the parents. A good series of developmental stages 

 of these larvæ was found; the description of these beautiful and 

 very interesting larvæ may well be considered the most important 

 part of this report. 



Finally the present collection is of considerable value for the study 

 of the zoogeographical distribution of the Echinoderms of Greenland. 

 The Echinoderms of West Greenland have for a long time been com- 

 paratively well known; through the Expedition of the "Alert" and 

 "Discovery" (Sir George N. Nar es), 1875 — 1876, those from the 

 northern Part of the West Coast (from 79° 20' N. lat. to 82° 87' N. 

 lat.) were made known (described by Duncan and S lad en in „A 

 memoir on the Echinodermata of the Arctic Sea to the West of 

 Greenland", 1881). The Amdrup Expedition, together with several 

 other Expeditions (Ryder, Kolthoff) brought to light the Echino- 

 derm-fauna of the East Coast, from Angmagsalik to about the 74° N. 

 lat. The dredgings of the Danmark Expedition further North, at 

 75°— 78° N. lat., in some way fill the gap, as it may be concluded 



17* 



