!55 



(254: 



brown; margin broad, black; seta small, dark. Claw light brown, dark brown 

 apically, with a dorsal denticle; setae as in P. nigri cor nis (Figure 455). 



FIGURE 444. P ot a m o ph y 1 a x st e 1 1 a t us Curt. Right foreleg (A), midleg (B), and hind 

 leg(C), posterior 



Case made of coarse sand grains,* slightly curved, slightly flattened 

 ventrally, rounded posteriorly, with obliquely truncate anterior margin. 



' Nielsen (1942; 540) found particles of plants and detritus on cases of larvae of medium and older stages. 

 There are no such cases in the collection of the Zoological Institute. 



319 



