248 Proceedings of the Royal Physical Society. 



Isotoma maritima, TuUb. 

 [Plate VII. Figs. 20-22.] 



Locally common on decaying wrack (Ficctis, etc.) on the 

 shores of the Firth of Forth. Specimens from the Dalmeny 

 beach are much larger than a series from the Fife coast at 

 Aberdour (length, 2J to 2J mm., as against IJ to If mm.); 

 but structurally they are the same. Identification confirmed 

 by Drs Schott and Schaffer. 



Schott (15) suggests that perhaps Lubbock's /. grisea is 

 identical with the present form. The description (second 

 antennal segment longer than third, etc.) seems to us, how- 

 ever, to agree better with that of Schaffer 's /. grisescens. 



I. maritima is recorded from Sweden, Finland, Germany, 

 and Bohemia. 



Local data. — Dalmeny beach (Linlithgowshire), on cast-up Fucus, etc. 

 (wrack), a few specimens on 31st Dec. 1898, and about thirty on 14th Feb. 

 1899 ; Aberdour (Fife coast), on rotting wrack, fairly common, 11th Feb. 



Isotoma grisescens, Schaffer. 



? Isotoma grisea, Lubbock's " Monograph." 



[Plate V. Fig. 4 ; Plate VII. Figs. 23-25.] 



Widely distributed, but as a rule not very common, 

 among dead leaves and under bark on old trees lying in 

 damp woods ; also among moss, etc. It has not previously 

 been recorded from the British Isles, unless it is the same 

 as Lubbock's /. grisea (from Kent ?), which appears to us 

 not improbable.^ We have found the species in Ireland. 



This form was described (13) from examples taken near 

 Hamburg by Dr Schaffer, who has kindly examined and 

 identified some of our specimens. It is intermediate between 

 /. olivacea, Tullb., and /. violacea, Tullb. — two closely allied 

 northern species, for mounted specimens of which we are 

 indebted to Dr Schott — agreeing with the former in the 

 short, even nature of its hairy covering with little or no 

 trace of outstanding bristles, but with the latter, as it seems 



^ In a recent paper (8) Sir John Lubbock treats /. grisea as having only two 

 teeth on the mucro, but we can see nothing to this effect in his original descrip- 

 tion of the insect, either in Trans. Linn. Soc. or in the ''Monograph." 



