Collembola and Thysanura of the Edinhurgh District. 237 



Sweden, Eussia, and Finland to France, Germany, Bohemia, 

 Hungary, and Italy. 



Lubbock (7) and Brook (1) state that this form is only 

 to be distinguished from the next {T. tridentiferus) by its 

 yellow colour when denuded of scales. We have, ho\vever, 

 found specimens of T. tridentiferus whose body-colour is 

 yellow ; but the true T. niger differs from that species in 

 well - marked structural characters. The spines on the 

 dentes are simple, not tridentate ; there are only two 

 teeth on the upper claw of the foot (five or six in T. 

 tridentiferus) ; and the lower claw is simple and tapering, 

 not broadly lanceolate and toothed, like that of T. 

 tridentiferus. The structural differences in the species of 

 this genus have been well figured by Tullberg (16). 



Local data. — Luffness, Aug. 1896, common ; Giflford, Sept., a few ; Uphall 

 (Liiilitbgow), Sept., half a dozen; Ravelrig, Oct., several; Bavelaw Wood, 

 near Balerno (Midlothian), April 1897, a few under bark of a dead fir lying 

 in a damp spot ; Longniddry (E. Lothian), Sept. 1897, common among wet 

 moss in an old quarry ; banks of Dalhousie Burn (Midlothian), March 1898, 

 several. 



Tomocerus tridentiferus (Tullb.). 



Tomoccrus plumhciis, Lubbock's "Monograph." 

 T. minor, Lubbock, Trans. Linn. Soc, 1862. 



Very generally distributed, and hy far the commonest 

 species of the genus here. Common also in other parts of 

 Scotland, in England, and in Ireland ; but apparently much 

 scarcer on the Continent, where it has been recorded only 

 from Scandinavia, Finland, Germany, and Bohemia; it is 

 likewise found in the Azores, and probably also in North 

 and South America. Like its congeners, and so many other 

 Collembolans, it occurs throughout the year — in winter as 

 plentifully as in summer, for cold seems to have little or 

 no effect on it — under stones, logs, etc., in all sorts of 

 situations, provided they are not too dry. 



Local data.— Arthur's Seat, Comiston, Colin ton Dell, TorduflF Hill, 

 Balerno, Kivknewton, East Calder, and Dalhousie, Jan., Feb., ^[arch, 

 and April 1896, abundant ; Charlestown, Aberdour, and Kinghorn (Fife), 

 Fob. and March, common ; Bucklyvie, April, and Aberfoyle, May, plentiful ; 

 Longniddry, Feb., a few; Morton and Braid Burn, near Edinburgh, July, 



