464 



ISOPODA. 



NORM ALT A. 



ONISCID.E. 



ONISCIDJZ. 



PLATYARTHRUS HOFFMANNSEGGII. 



Specific character. Opaque -white. Upper surface of the animal scabrous, 

 with compressed scale -like club-shaped prominences. Posterior margins of 

 the segments sub-serrated. 



Length, one to one and three- quarters of a line. 



Platyarthrus Hoffmannseggii. BRANDT, Bull. Soc. Nat. Moscow, vi. p. 174, 



pi. 4, fig. 10 (antenna, absq. descr. specifica). 



HOGAN, in Nat. Hist. Rev. vi. p. 109. 



KINAHAN, in ditto, p. 127. 

 Itea crassicornis (?). KOCH, in Contin. Panzer Ins. Deutschl. 186, 



fol. 5 ; and Deutschl. Crust. &c. 36, 5. 



THIS curious little species has much the aspect of a 

 Porcellio ; it is, however, considerably broader in propor- 

 tion to its size, the smallness of which, moreover, together 

 with its opaque-white colour, broad short antennae, sub- 

 terrestrial and ant-loving habits, well distinguish it. 



The head is broader anteriorly than posteriorly, deeply 



