THE CANADIAN ENTOMOLOGIST 383 



Prosternal teelh mostly 3 + 3 or 4 + 4. in the litter case the inner- 

 most and the outermost on each side decidedly smaller than the two inner 

 ones. 



Angles of the ninth, eleventh and thirteenth dorsal plates produced, 



Coxal pores rather large, round or oval, each enclosed in a large, 

 circular pale area, which in some might be supeificially regarded as the 

 pore ; 3, 4, 4, 4, 4. 



Tarsi of all legs biarliculate. 



None of the coxa: armed laterally or ventrally, the last five pairs 

 (those bearing pores) with a ^hort, stout spine dorsally. 



Spines of the first legs t,, t„ 3 ; of the penult i, 3, 3, 2, with two 

 claws; of the anal i, 3, 3, i, the claw single. 



Anal legs of male of moderate length, slender; the fifth joint con- 

 spicuously bowed ventrad, and flattened and longitudinally furrowed above 

 or dorsally. 



Claw of the female gonopods entire or weekly notched at apex; basal 

 spines ^ + 3. 



Length of adults up to 39 mm.; width, 4 mm.; length of antennae 

 and anal legs ad 13 mm. 



Localities. — Sausalito (type locality) and Oroville. 



Two adult males were secured at Sausalito, and numerous males and 

 females were taken at Oroville. They were found for the most part under 

 stones and other objects lying in open treeless areas. Tliey are slow to 

 take alarm, often lying quite unconcerned after stones have been rolled 

 from over them and they themselves jarred, and seem in every way more 

 sluggish than the species of Lithobius and related genera. 



9. ZygetJiobhis sokarienus, sp. nov. 



Conspicuously attenuated from region of the tenth dorsal plate 

 cephalad ; dorsum well arched, shining. 



Dorsum reddish brown or chestnut, the head and ultimate segments 

 darker, the coloration of the head uniform. Antennae dark reddish brown 

 proximally, becoming pale distad ; prosternum with prehensorial feet, and 

 the venter brown, often of reddish tinge, the posterior segments of the 

 venter darker. Legs usually brown, sometimes dark except proximally 

 and distally, and the posterior pairs usually darker than the others. 



Antennae moderately long, but not quite equalhng half the length of 

 the body. Articles 38-39, the first two long, the next twelve abruptly 

 and also narrower, those beyond the fourteenth longer and more loosely 



