678 MR JAMES MURRAY 



M. islandicus, Richters. — Though not definitely known to exist in Spitsbergen. 

 some eggs found in Prince Charles Foreland and Recherche Bay (Plate I. figs. 2 and 3), 

 though not exactly like Richters' figure (" Islandische Tardigraden," p. 376), may belong 

 to this species. 



Macrobiotus, sp. (Plate I. fig. 4.) — A large egg, with hemispherical processes, also 

 occurring in Novaya Zemlya and on Ben Lawers in Scotland. The species producing 

 it is not yet known. 



Genus Diphascon. 



D. chilenense, Plate (9). — Prince Charles Foreland. Previously known as an Arctic 

 species only from Tromso. 



D. alpinum, Murray (6). — Prince Charles Foreland. Now known as Arctic, 

 Antarctic, and from one mountain top in Scotland (6). 



D. spitsbergense, Richters (11). (Plate II. fig. 12.) — Prince Charles Foreland 

 Spitsbergen ; Carpenter's Rock, Franz Josef Land. 



D. scoticum, Murray (5). — Prince Charles Foreland and Recherche Bay, Spitsbergen ; 

 Cape Gertrude, Franz Josef Land. Of smaller size than D. spitsbergense, and easily 

 known by the much more slender gullet. Only, as yet, known in northern lands. 

 Three eggs in skin. 



D. angustatum, Murray (4). — By the two narrow rods in the pharynx, the animal 

 figured (Plate II. fig. 11) comes nearest this species, but has the rods narrower and 

 the first relatively longer. It attained a length of 38(V. The encysted animal was seen. 



Diphascon, sp. (Plate II. fig. 10.) — This insufficiently observed species has the 

 rods in the pharynx as in D. angustatum, but is undoubtedly distinct, as the pharynx 

 is relatively shorter and broader, and the gullet is very slender. 



Diphascon, sp. — -Also insufficiently studied, but distinct from all known species. 

 There are four short rods in the pharynx, besides a nut and a comma. In this respect 

 it resembles, among known species, only D. chilenense, but it has a thick gullet, 

 relatively short. The claws are of the usual Diphascon type. 



Summary. 



Including the species found in Mr Bruce's collections, there are 40 species of Arctic 

 Tardigrada on record. There are in addition 4 undescribed species which require 

 further study, making a total of 44 species. Five of these species are as yet unknown, 

 except in the Arctic Regions. 



There are 32 of the Arctic species also found in Scotland, 17 in Central Europe, 

 9 in Asia, 5 in Africa, 6 in America, while 8 extend into the Antarctic Region. 



Several of the records are of doubtful value — some of them refer to insufficiently 

 described species, for ever unrecognisable — yet the majority are good species, and 



