180 



Proceedings of the Royal Irish Academy. 



Porcellio laevis Lntieille. 





35 



34 



40 



39 







33 



36 



37 



27 



28 



29 



32 







26 



25 



30 



31 



i6 



17 



24 



23 



22 





15 



18 



19 



21 



9 



10 



14 



13 



20 



2 8 



7 



11 



12 





1 4 



5 



6 







3 











This species appears to be faiily 

 common in the neighbourhood of 

 Dublin (11. F. S.) ; but elsewhere in 

 Ireland it must be considered rare. 



The only localities outside Co. Dublin 

 from which we have records of it 

 are: Tralee, N. Kerry, (Mrs. R.) ; 

 Cappagh, Co. Waterford (P. A. U.) ; 

 Galway City (C. Chilton) ; Enniskerry, 

 Co. Wicklow (A.W. S.); Drogheda, 

 Co. Louth (R. W.) ; Richhill, Co. 

 Armagh (N. H. F.) ; and Belfast, Co. 

 Antrim (R. W.). In England it is 

 recorded from only a very few localities 

 in the south-east ; but it has perhaps 

 the widest general distribution of any 

 species of Woodlouse, ranging as it does 

 over the whole world, with perhaps 

 the sole exception of the Australasian 

 region. 



METOPONORTHUS. 



The genus Metoponorthus appears to have a world-wide distribution, but 

 the majority of species are European. Three species only have been taken in 

 Ireland, and one of these has not yet lieen found in England. 



The following characteristics serve to distinguish the three species : — 



Species.' 



A. Three pairs of tracheae, oval body, .... cingendus. 



B. Two pairs of tracheae, oblong body. 



(a). Epistoma or clypeus has a curved ridge run- 

 ning transversely across it ; telson produced 

 into a sharp point, ..... pridnosxi,s. 



Ih). Epistoma or clypeus smooth, without transverse 



ridge ; telson short, triangular, . . . melanurus. 



Metoponorttus pruinosus (Brandt). 



Found almost exclusively in hot- 

 houses and frames, or close to them 

 outside in the summer time, this species 

 is, we think, certainly not a native of 

 this country, though we have two 



records of its having been taken in the 

 open country, first under stones at the 

 mouth of the Boyne liver, Co. Meath, 

 by Dr. Scharff in 1894, and again in 

 an old quarry near Greystone.", Co. 

 Wicklow, by Mr. N. E. Stephens in 

 1909. Professor Kinahan states that 



' These chiiracteristics are those given by M. Budde-Lund in his " Isopoda Xerreslria." 



