Clare Island Survey — Arctiscoida. 37 13 



species. With the Canadian Water-bears there was associated in Ireland 

 a Canadian Bdelloid Eotifer. This fact strengthens the idea that this 

 " Atlantic " distribution may be due to some real community of conditions. 



Marine species. — Echiniscoides sigismundi is the first marine Water-bear to 

 be recorded for the British Isles, and the Irish form has some peculiarities not 

 previously noted. 



Rare and local species. — About one-half of the Irish species are cosmopolitan 

 or widely distributed. The others are more or less limited in their range. 

 Some of these have been already noticed under the Arctic, Canadian, and 

 Marine species. Others show various peculiarities in distribution. E. gladiator 

 is in the British Isles, Canada, and New Zealand, but the variety exarmatus 

 only in Britain and New Zealand ; M. harmsworthi in Europe, Australasia, 

 and the Arctic ; M. hastatus in Britain and Switzerland , M. papillifer in 

 Britain and Australasia M. annulatus in Britain, New Zealand, and the 

 Arctic; M. schaudinni and Diphascon angustatum in Britain and the Arctic. 



No doubt further work in other countries will greatly modify our ideas of 

 distribution, but some species (such as M. augusti and M. hastatus) appear to 

 be, from some unknown cause, extremely restricted in their range, as among 

 hundreds of apparently suitable locations they will be found only in one here 

 and there, or even in a single spot. 



Conclusion. — As the thirty-three species of Water-bears were all collected 

 in a small part of one county, it cannot be supposed that the list is fairly 

 representative of the whole of Ireland. When other parts of the country, 

 offering varying conditions, come to be studied, it would not be surprising if 

 the list were easily doubled. As there appear to be no earlier records of 

 Irish Water-bears, all thirty-three species are new for Ireland. As indicated 

 in the table on p. 3, there are eleven species which are new records for the 

 British Isles, making the Britannic list up to sixty-one species. [See Murray 

 (16) in Bibliography.] 



Bibliography. 



There is no bibliography relating to Irish Arctiscoida ; but as this is the 

 first paper dealing with this group in Ireland, references are given to the 

 works in which the student will find further information about Water-bears 

 in general, and especially about the species here recorded. 



1 DoYfeEE, M. L. : 



Memoire sur les Tardigrades. Ann.Sci.Nat.,Ser.2,T.xiv,Zool.,p.269. 1840. 



2 Dujakdin, F. : 



Sur le Tardigrade, etc. Ann. Sci. Nat., Ser. 2, T. x, Zool., p. 181. 1838. 



3 — SurlesTardigrades.etc. Ann.Sei.Nat.,Ser.3,T.xv,Zool.,p.l60. 1851. 



