34 MR JAMES MURRAY 



Diphascon alpinum, Murray (4). (Plate IV. figs, lla to Uc.) 



Specific Characters. Long, narrow, whitish or hyaline; one pair of claws, short and 

 very thick, with conspicuous short supplementary point on one claw, the other pair 

 with one very long claw, having a fine supplementary point. Teeth short, curved, 

 with bearers ; gullet very long, slender, pharynx shortly oval, three rods and a short 

 nut in each row. The rods increase both in length and thickness from the first to the 

 third, which is about three times as long as broad. 



The S. Orkney examples are much larger than the Scotch ones, reaching 360 M in 

 length. The only other difference is the fourth small nut in the rows of pharyngeal 

 thickenings. This little nut at the end of the row is in many species of Tardigrada 

 very obscure, very doubtfully of the same structure as the other rods, and at any rate 

 of too uncertain a character to be regarded as of any specific value. 



NOTES. 



Taking a general view of the preceding somewhat meagre list of Tardigrada, the 

 most striking feature of it is its very slight correspondence with the Tardigrade fauna 

 of other parts of the world. It differs not only from the fauna of the temperate regions, 

 which we know best, and from that of the arctic region, which has been pretty well 

 studied, but from that of the only other part of the antarctic region which has been 

 studied (12) ; indeed it differs more from the last than from the others. 



Every one of those regions has a number of peculiar local species, mingled with 

 others which are widely distributed. 



Only two of the S. Orkney water-bears have been identified, and a third doubtfully. 

 We cannot, however, suppose that we have anything like a complete, or even a fair, 

 knowledge of the Tardigrada of the South Orkneys. The fifteen forms enumerated were 

 obtained practically from one large tuft of moss. A second minute scrap yielded only 

 a few examples, which were of species plentiful in the larger sample. If mosses from a 

 variety of situations could be examined in the fresh condition, it is likely that others of 

 the widely distributed kinds would be found, as well as perhaps still other local species. 



The Tardigrada would appear to be best adapted to live in temperate or cold regions. 

 They are very numerous in Scotland ; in Spitzbergen they are also plentiful and the 

 largest known species are found ; while in the only parts of the southern hemisphere 

 which have been studied, the Tardigrada are a conspicuous element in the moss-fauna. 



A large series of samples of moss from India has been recently examined for Tardi- 

 grada, and though some of them came from elevations of 7000 to 8000 feet, near Darjeel- 

 ing, and there were a few peculiar species, they were, on the whole, very scarce. 



No doubt, with fuller information as to the many species here referred to as " doubt- 

 ful," several could be referred to known species, though several others are almost certainly 



(ROY. soc. EDIN. TRANS., VOL. XLV., 332.) 



