Report on the Echinoderms of North-East Greenland. 285 



the species Trochostoma boréale (Sars) as understood by Ludwig 

 and by me in the paper quoted becomes = Molpadia oölitica (Poui- 

 talès), M. arctica (v. Marenzeller) and M. parva (Théel). 



Nevertheless Clark gives the same distribution for Molpadia 

 oölitica as do Ludwig and Edwards for Trochostoma boréale 

 (oöliticum). This result comes about through regarding Tr. boréale 

 and oöliticum as synonyms, the latter being widely distributed along 

 the North American East Coast, from the West Indies to New Found- 

 land. Though I have not myself examined any specimen of the 

 American M. oölitica, I would on zoogeographical grounds doubt its 

 identity with M. borealis. 1 would venture to suggest that M. oölitica 

 may perhaps be a zoogeographical parallel to Echinarachnius parma, 

 occurring at both the Pacific and the Atlantic side of North America. 

 (See below, p. 299). 



On a renewed examination of the specimens from the Amdrup 

 Expedition I find the three specimens from Flemming Inlet to be M. 

 arctica (v. Marenzeller). The specimen from off Angmagsalik, which 

 was taken together with the decidedly boreal or Atlantic species : ^ 

 Pentagonaster granularis, Ophiacantha anomala and Ophioscolex pur- 

 pureas, might beforehand be supposed to be one of the Atlantic 

 species. It bears, in fact, a considerable resemblance to M. Blakei 

 (Théel) but differs from that species in some points, among which 

 the presence of anchors appears, according to the researches of H. 

 Lym. Clark, to be the least important. Possibly it is a new spe- 

 cies, but on account of the scant}' material in hand, and in view 

 of the great difficulties in distinguishing the species within this 

 genus I prefer to regard it only as a variety of M. Blakei, to which 

 species it is, in any case, most nearly related. I shall give here a 

 a description of it, under the name of 



Molpadia Blakei, var. gröulandica п. var. 



The single specimen is 3U mm long, including the distinct caudal 

 appendage, which is 5 mm long. Anal papillæ appear to be wanting. 

 The 15 tentacles have one short digit on each side. The radial 

 pieces of the calcareous ring with distinct bifurcate prolongation. 

 The skin is thin, somewhat translucent, rough from the projecting 

 spires of the calcareous corpuscles. The deposits of the skin are 

 anchors and tables, but no phosphatic corpuscles. 



The anchors, which are rather numerous, are of the usual 

 shape, with two arms, slightly indentated on the outer side (Fig. 5 a); 



' Unfortunately the Expedition did not take the bottom temperature on the dred- 

 ging stations. But the fauna on this station does not leave any doubt but that 

 this was a ^varm-лvater station. 



XLV. 20 



