TARDIGRADA: PACIFIC ISLANDS 151 



LIST OF SPECIES 



Echiniscus mutabilis, Murray. Macrobiotus hufelandii, Schultze. 



E. novazeelandice, Richters. M. occidentalis (?), sp. n. 



E. intermedius, sp. n. M. intermedius, Plate. 



E. viridis, sp. n. M. crassidens, Murray. 



E. spimdosus, Doyere. M, oberMuseri, Doyere. 



E. perarmatus, Murray. Diphascon scoticum, Murray. 



Milnesium tardigradum, Doyere. 



Three species not identified (1 Echiniscus, 2 Macrobiotus) 



Genus Echiniscus 

 A : SEGMENTS V. AND VI. SEP ABATE 

 Echiniscus mutabilis, Murray (12) 



The commonest species in Hawaii. The form of Echiniscus recorded below as 

 E. novcezeelandioi has the characteristic dorsal processes so reduced in size that it 

 may be questioned whether it should not rather be regarded as a form of E. mutabilis. 

 At any rate it is a transitional form from the one species to the other, and indicates 

 how closely related they are, although their types differ so conspicuously. 



Echiniscus novazeelandice, Richters (37) (Plate XIX.) Fig. 35 



The form of this species which occurred in Hawaii differs from the typical 

 examples found in New Zealand and Australia in the extreme reduction of the dorsal 

 processes on the third pair of plates. They are mere knobs or sometimes only angles 

 of these plates. 



Only a few examples were seen. They measured about 240 /* in length, exclu- 

 sive of the legs. The setse a were more widely spreading than usual, and were 60 n 

 long. 



B: SEGMENTS V. AND VI. UNITED 



Echiniscus intermedius, Murray (Plate XIX. Figs. 36c, 36d) 

 See description in Australian Tardigrada, p. 129 of this volume, also in Canadian 



Tardigrada, p. 161 



This most interesting little species occurs in Hawaii as a peculiar variety. The 

 type as found in Queensland and the variety found in Canada differ so much that 

 they would be considered as distinct species, were it not for the Hawaiian variety, 

 which is intermediate between them. The type has the plates marked with large but 

 very faint hexagons, the Canadian variety has very fine pellucid dots ; the Hawaiian 

 form has markings of intermediate size, but they are depressions like those of the 



