Collembola and Thysanura of the Ediriburgh District. 253 



the west coast of Ireland. It is very closely allied to /. 

 crassicauda, Tullb., which has been recorded from Shetland 

 by Renter (12), but may be readily distinguished by the less 

 robust dentes and less pointed mucrones of its spring (Fig. 10). 

 Schott's name being preoccupied, Dalla Torre has renamed 

 the species after its discoverer. The colour is described as 

 " rotbraun " by Schott, but in our specimens it varies from 

 brownish-violet to blue-violet : colour, however, is a very 

 uncertain character in this group. 



Local data. — Craigentinny beach between Leith and Portobello, a few, 

 along with Achorutcs viaticus, on rotting wrack, 14tli Jan. 1899. 



Family PODURID.ffi.i 

 Genus Podura, Linnaeus. 



Podura aquatica, Linn. 



Locally common on the surface of stagnant water. As yet 

 we have met with it only in East Lothian. It occurs com- 

 monly in England and Ireland, and abroad it is a species of 

 the widest range — Siberia, all Europe, Greenland, and ISTorth 

 America, 



Local data. — Gullane, Aug. 1896, abundant on surface of water in old 

 quarry; Longniddry, Aug. 1898, in some numbers in a similar situation. 



Genus Xenylla, Tullberg. 



Xenylla humicola (O. Fabr.), Tullb. 



Achorutes Mimicola, Lubbock's "Monograph." 



[Plate VIIL Figs. 11-14.] 



Occurs locally among rotting wrack on both shores of 

 the Firth of Forth. Drs Schott and Schaffer have kindly 

 examined some of our specimens, and concur in referring 

 them to this form, hitherto known only from Greenland, 

 Behring Island, ISTovaya Zemlya, Finland, and North-West 

 Germany. The colour is a nearly uniform bluish or purplish 

 black. The very closely allied form, X. maritima, Tullb., 

 has been recorded from Jersey by Brook (1), and Carpenter 

 has obtained it from the coast of Ireland. 



^ = Schott's Lipuridse. 



