No. 26.] ARTHROSTRACA OF CONNECTICUT. 247 



1905. Porcellio rathkei, Paulmier, Bull. N. Y. State Mus., 

 No. 91, p. 183. 



Body oval, somewhat broader in female than male; dorsal 

 surface rather convex and slightly tuberculated. Head with 

 lateral lobes well developed, rounded ; frontal lobe short, obtusely 

 triangular. 



Second pair of antennae rather slender, nearly one-half as 

 long as body; flagellum about as long as last joint of peduncle 

 and made up of two joints of which the proximal one is shorter 

 than the terminal one. 



Thorax with coxal plates moderate, subcontiguous, and with 

 posterior corners obtusely acuminate. Last pair of legs stronger 

 in male than female and with carpus remarkably dilated near the 

 base. 



Abdomen scarcely one- fourth as long as whole body; third 

 to fifth coxal plates well developed and recurved. Opercular 

 plates all provided with air spaces. Telson subtriangular, with 

 outer part acutely produced and smooth above. Uropods with 

 outer rami broadly lanceolate and with the inner ope extending 

 considerably beyond the last abdominal segment. 



Color, variable. 



Length lo mm. 



Distribution : Europe ; Ohio ; New York City ; Lake Cham- 

 plain; Michigan; Maine; Massachusetts; Providence, Rhode 

 Island; New Haven, Connecticut; Washington, District of Colum- 

 bia ; Texas ; Georgia. 



The species is very common under stones, boards, etc. It is 

 found very often in woodsheds and greenhouses. 



It is distinguished from the other species of the genus by its 

 white spots on a gray to black ground; and by the antero-lateral 

 lobes of the head which are smaller than in P. spinicornis. 



Metoponorthus pruinosus (Brandt). 



1899. Metoponorthus pruinosus, G. O. Sars, Crust. Norway, 

 vol. 2, p. 184, pi. 80, fig. 2. 



1902. Metoponorthus pruinosus, Stoller, 54th Rept. N. Y. 

 State Mus., p. 213. 



1905. Metoponorthus pruinosus, Richardson, Bull. U. S. Nat. 

 Mus., No. 54, p. 627. 



