LIST OP THE ISOPODA. 219 



*' This species swarms in the Dee, where it bites 

 bathers." W. 



Family II. — SpHiEROMiDiE. 



Sphcsroma serratum, Fabr. 



Colwyn Bay; Mersey, above EUesmere Port, under 

 stones. W. 



Family III. — iDOTEiDiE. 



Idotea tricuspidata, Desmarest. 



Colwyn Bay, Dee, etc. W. 



Idotea linearis, Pennant. 



Along the coast. 



These two species of Idotea are often found on floating 

 drift weed. W. 



Arcturns longicornis, Sow. 

 Dredged at the mouth of the Dee. Byerley. 



Family V. — Asellid^. 



Jaera albifrons, Mont. 

 Colwyn Bay and Rhos Bay, in tidal pools. W. 



Janira maculosa, Leach. ' 



Bar of the Dee. W. 



Limnoria lignomm, Rathke. 



Dee and New Brighton. Bate and Westwood. 



Byerley records this species from the Mersey, under the 

 name of L. terebrans, and states that the wooden piles of 

 the Rock Lighthouse are completely drilled by it. 



" I have never seen or heard of any signs of this wood- 

 boring pest in the Dee, though I have asked men who have 

 removed old piles." W. 



