332 THE SCOTTISH NATURALIST 



Westwood ^ mention having received examples of vS. 

 aciiininata, Leach, from Cumbray. 



I append the following notes on the species of Idotea : — 



1. Idotea baltica (Pallas). — Plentiful in the rock pools 

 on both the east and west shores, also a small variety or 

 subspecies, taken in the east shore rock pools, which differs 

 from the type in a number of minor structural features. 



2. Idotea granulosa, Rathke. — Fairly common on 

 seaweed in the west shore rock pools. Sars - gives the 

 dimensions as follows — " Length of adult female 1 1 mm., 

 of male 15 mm.," whereas our largest males measure 19 mm., 

 and the females 12 mm. 



3. Idotea neglecta, G. O. Sars. — Only met with once, 

 and few in numbers. Dr Thomas Scott has recorded it from 

 the Moray Firth.^ 



4. Idotea viridis (Slabber). — A few fine specimens 

 were collected on a single occasion off masses of seaweed in 

 the west shore rock pools. Norman {op. cit., p. 442) mentions 

 that this species is essentially an inhabitant of brackish 

 water. 



5. Idotea PELAGICA, Leach. — Rare ; specimens rather 

 undersized. I have also examples from the Bay of Nigg, 

 kindly sent me by Dr Thomas Scott. Bate and Westwood 

 {pp. cit.) record specimens from the Bell Rock. 



6. Idotea EMARGINATA, Fabr. — After /. baltica (Pallas), 

 this is our commonest species. 



7. Idotea linearis (Pennant). — Fairly plentiful at the 

 estuary of the Eden and in rock pools on both shores. From 

 those on the east I have a form which does not exhibit the 

 longitudinal markings, and the whole of the dorsal surface 

 of the mesosome is rough and the metasome depressed. 



Idotea inetallica, Bosc, has not yet been found in the bay, 

 but a species which I regard as new has been discovered, 

 the description of which I hope to give in a future paper. 



^ Hist. Brit. Sessile-eyed Crust. ^ 1868, vol. ii., p. 395. 



2 Crust. Norway, 1899, vol. ii., p. 83. 



3 i^nd Rep. Fish. Bd. for Scot., 1904, p, 257. 



