192 



Side-plates of 1st segment of raesosome abruptly truncated at the posterior corner. 

 Last segment of metasome much broader than it is long, and obtusely truncated 

 at the tip. Antennse very short, with the last joint of the flagellum nearly 3 

 times as long as the 1st. Legs, pleopoda and uropoda nearly as in A. pictum. 

 Colour of dorsal face dark brown, more or less distinctly variegated with lighter 

 patches, arranged as in the above-named species. Length of body scarcely exceed- 

 ing 5 mm. 



Remarks. In its general appearance this species bears considerable resem- 

 blance to A. pictum, and may easily be confounded with it. On a closer exa- 

 mination, it is however found to differ very markedly in certain points, and may 

 thus undoubtedly be regarded as specifically distinct. The peculiar form of 

 the side-plates of the 1st segment of the mesosome is an especially marked cha- 

 racter, and the caudal segment also differs essentially in its form. 



Occurrence. I have myself only met with this species in a single locality 

 near Christiania, viz., close to the shore on the outermost point of the Ladegaardso, 

 where it was found occasionally below stones together with Porcettio pictus. Mr. 

 Ellingsen has, however, collected it in 3 different places, viz., at Kragero, Grim- 

 stad and Boro, and some few specimens in our Univ. Museum were also found among 

 A. pictum, and were collected at Langesund by the late Dr. Jensen. In habits 

 it exactly resembles A. pictum. 



Dstribution. Northern and Central Europe, in the same places as A. pictum. 



