9 6 



THE BRITISH WOODLICE. 



The fact that Porcellio dilatatus is more than half as broad 

 as it is long at once distinguishes it from the other species of 

 Porcellio. It is tuberculated and of somewhat 

 a lighter grey than Povcellio scaler usually is. 

 The two species agree in having the two joints 

 of the flagellum equal, hut the last peduncular 

 joint, as in Porcellio pictus, is longer than the 

 flagellum. 



As in the two preceding species, air-tubes 

 are found in the outer plates of the appendages 

 on the first two abdominal segments. Porcellio 

 dilatatus is to be looked for near houses. 



BRITISH L CA LITIES : — 



England: Maldon ; (W.M.W. from R.M.) : 

 Eton; (Stebbing from W.M.W., 71a): Berk- 

 hamsted ; (Norman, 50) : Headley, Surrey ; 

 Ventnor ; (Stebbing in Norman, 49). 



Ireland : Dublin ; (ScharfT, 63) : Dundrum ; 

 (Scharffin Norman, 50) : Gal way ; Roundstone ; 

 (R.F.S.) : Belfast ; (C. W. Buckle, Irish Nat., Vol. XI. (1902), 



P- 43)- 



FOREIGN DISTRIBUTION :— 

 Europe : France; (25) : Spain; (12J ; Denmark ; Norway ; Germany; Poland; 

 Holland; (59). 



Africa : Madeira ; Azores ; (24). 

 Australia: New Guinea; (59). 



FIG. 49. — FLAGELLUM 

 AND LAST PEDUNCULAR 

 JOINT OF THE ANTENNA 



of Porcellio dilatatus. 



Porcellio rathkei Brandt. Plate XVI. 



1833 Porcellio rathkei Brandt (3), p. 177, fig. 10. 



1833 Porcellio ferrngvieus Brandt (31, p. 178. 



1840 Porcellio trilineatus Koch (34). part 34, pi. IX. 



1853 Porcellio trivittatus Lereboullet (39), p. 54, pi. I., figs. 13 and 14. 



1853 Porcellio tetramoerus Schnitzler (65), p. 24. 



1853 Porcellio strialus Schnitzler (65), p. 24. 



There is often a light band down the back and one on either 

 side of it near the margin in Porcellio rathkei (especially in the 

 males), with other more irregularly arranged light patches 

 between. Unlike the three species previously considered, the 

 present one has a smooth body. The distal joint of the flagellum 

 is the longer, and the flagellum itself is equal in length to the 

 last joint of the peduncle. 



