ON THE TARDIGRADA OF THE SOUTH ORKNEYS. 27 



barbs ; head setae long, with expanded base, and separate palp alongside ; palp on first 

 leg, none seen on last leg. 



Length of one example 164 M, of the other 200 M. Fringe absent from the smaller 

 one, obvious on the larger, no other difference. Both appeared as if they might be alive, 

 but in the state of rigor. They did not, however, wake up. The flesh was not wasted 

 as in all the other Tardigrada found, and I was able to mount them. The colour is 

 yellowish, the granules very small. 



On account of variability of the processes of Echiniscus, and possible changes in the 

 course of development, Professor RICHTERS advises that no species be described as new 

 unless we have evidence of maturity in the presence of skins with eggs, or there are 

 striking peculiarities of some sort. I have shown, further (2), that even after maturity 

 is reached there may be further development of the processes, as well as great increase 

 in size, during successive moults. 



As the eggs have not been seen, this species must be distinguished by the various 

 processes, the arrangement of which does not closely approach any described species. 

 It is nearest to E. merokensis, Eichters (13), but differs in many little points. That 

 species has the lateral setae after the first paired plates longer that the dorsal, lacks the 

 lateral short spines after the second paired plates, has a straight spine on the outer 

 claws, and is figured as coarsely granular. Still closer is the resemblance to an un- 

 described species of which Mr BRUCE made a sketch in Franz Josef Land, but that also 

 has the lateral setae of the first paired plates longer than the dorsal, has lateral setae 

 instead of short spines at the second paired plates, etc. 



The lumbar plate of E. meridionalis has five facets, one dorsal, two lateral, and two 

 posterior (forming the tail-piece), and the species figured by Mr BRUCE corresponds in 

 this respect. 



Echiniscus, sp. (Plate I. fig. 4.) 



Specific Characters. Of medium size, plates ten, arrangement normal, granules small. 

 Processes, on each plate of first pair a long dorsal seta, and a small one close beside 

 it, on each plate of second pair a small triangular dorsal tooth, on the lumbar plate 

 a pair of very long curved setae, each with a short branch about the middle, 3 median 

 plates. The species has no close resemblance to any known species, and the peculiar 

 branch, like the tine of a stag's horn, on the curved lumbar seta, might suggest such a 

 name as " the Stagshorn Echiniscus " (Cervicornis). As, however, the study is so 

 incomplete, and the head and legs have not been seen, so that we know nothing 

 of the head setae, fringe, or claws, it would be premature to give the form a name. 

 I know of no species described which has branched setae, though E. Duboisi (8) has 

 serrate spines. 



(ROY. soc. EDIN. TRANS., VOL. XLV., 325.) 



