252 Proceedings of the Royal Physical Society. 



Isotoma spitzbergenensis, Lubb. 

 [Plate VIII. Figs. 5-8.] 



Half a dozen specimens clearly referable to this species, 

 described only last year (1898) by Lubbock (8) from Spitz- 

 bergen, were obtained on the beach at Dalmeny, a few miles 

 west of Edinburgh, in January 1899. They were found by 

 shaking bunches of rotting wrack {Fuciis) over a sheet of 

 white paper, and were fairly common, but, owing to their 

 minuteness and agility, it was no easy matter to secure 

 them. A month later it was met with rather plentifully 

 on other parts of the shores of the Firth of Forth. 



The long terminal and two upright basal teeth to the 

 mucro (Fig. 8) readily distinguish the species, which is rather 

 nearly allied to /. schotti, D. T., and 7. crassicauda, Tullb., 

 both characteristically northern and arctic forms. The types 

 of this Spring-tail were collected at Dickson Bay, Spitz- 

 bergen, in July 1896. It forms an interesting addition to 

 the British fauna. 



Local data. — Beach at Dalmeny Park, Linlithgowsliire, fairly common on 

 cast-up wrack, 10th Jan. 1899 ; Musselburgh (Midlothian) and Cockenzie 

 (E. Lothian), common on wrack, 9th Feb.; S, Queensferry, common, 14th 

 Feb.; Aberdour, two, 11th Feb. 



Isotoma schotti, Dalla Torre. 



Isotoma litoralis, Schott {nee Moniez). 



[Plate V. Fig. 6 ; Plate VIII. Figs. 9, 10.] 



This is another characteristically northern Isotoma, which 

 we have obtained off rotting wrack on the southern shore of 

 the Firth of Forth, the locality in this instance being on the 

 beach between Leith and Portobello, where a few specimens 

 were secured in January 1899. [We have since (in Sept.) 

 found it in abundance on the surface of water at Methven 

 Bog, near Perth, an inland locality.] 



The species was described in 1893 by Schott (15), who 

 had examined specimens from Spitzbergen, Sweden, and 

 Finland. Schaffer (13) obtained it from the mouth of the 

 Elbe, and Carpenter (" Proc. Dublin Micro. Club," in Irish 

 Naturalist, vol. vii., 1898, p. 54) recorded it last year from 



