spaced, thin, brown, large spines, basal spine slightly thinner and longer 

 than apical spine. Primary ventral setae of hind femur (Figure 531, C) 

 situated close together in middle of segment, basal seta in form of a large, 

 thin, brown spine; apical seta black, moderately long. Secondary dorsal 

 setae present only in distal part of legs. 



Dorsal and lateral processes of abdominal segment 1 large, well 

 developed; 12 — 14 small, black setae on small, pale, sclerotized dots 

 anteriorly, and lateral to dorsal process; ventral side of segment with 

 2 small, median, brown sclerites. 



Lateral line on segments 3—8 with small, light hairs. Gills on 

 segments 2 — 7. 



Postsegmental gills of segment 2 and gills of segment 3 well developed, 

 larger than the others ; dorsal and ventral rows of segments 6 and 7, and lateral 

 row of segment 4 and (if present) of segment 5, always with short, thin, 

 sometimes small and rudimentary, gills. 



Number and arrangement of 



gills of Ch.' 



V i 1 lo sa 





Segment 



Dorsal 



Pleural 



Ventral 



2 



1 

 1 



1 



1 



1 



1 



3 



1 



1 



1 



1 



1 

 1 



4 



1 



1 



1 (0) 



1 (0) 



1 

 1 



5 



1 



1 



1 (0) 





1 

 1 



6 



1 (0) 

 1 (0) 







1 

 1 



7 









1 

 1 (0) 



Tergite of abdominal segment 9 chestnut brown, with distinct punctation 

 at anterior margin; setae black; medioanal setae thick, long; anterior - 

 angle setae similar but shorter; interm.ediate seta moderately long; lateral 

 seta short, thin; a long seta between medioanal setae; 5—6 setae on and 

 around tergite (Figure 532). 



Sclerite "b" of anal legs brown, with dark punctation at basal margin; 

 large setae black; medioanal seta long, thick; neighboring seta slightly 

 shorter; lateral seta thinner and shorter; naedian subapical seta the same; 

 apical ventral seta strong, thin, moderately long; surface with 3—4 short, 

 thin, and 2—3 small setae (Figure 532). 



Sclerite "c" brown, with broad, black, lateral margin; seta small, strong, 

 black. 



Claw yellowish brown basally, pointed, reddish brown at apex, setae as 

 in Ch. sahlbergi. 



Case 14—18 mm long, including an additional rod, 2 6—2 7 mm, made of 

 sand grains or together with detritus, with smooth surface if made only of 



381 



