^ Number and arrangement of gills of B. subnu- 



^0 '3Jbilus (after Siltala.with modifications) 



375 



Segment 



Dorsal 



Ventral 



2 



5-6 



1 (0) 



3 



4-6 



1 



4 



4-6 



1 



5 



3-6 



1 



6 



3-6 



1 



7 



2-3 (0) 





situated on suture; several small spinules further basally; anterior apical 

 ventral seta represented by large^ light spine, subapical seta in form of a 

 similar but larger spine; several small spinules basal to former spine; 



posterior ventral setae, apical and 

 subapical, situated near anterior setae, 

 light, small, slightly longer and thinner. 



Femur long, with slightly convex 

 dorsal and ventral margin; apical 

 dorsal seta and basodorsal seta short, 

 light, thin; 4—5 short, secondary setae 

 between them, 3—4 smaller setae 

 further basally; one posterior and 

 1—2 short, thicker, anterior, subdorsal 

 setae nearby in distal half; 1st of 

 2 primary ventral setae situated sub- 

 apically, the 2nd closer to middle of 

 segment, both short, light, the 2nd 

 slightly longer and thicker; small, 

 light, spine- shaped, secondary setae 

 about the same size, situated at 

 intervals along ventral margin; between 

 them, 9—12 groups of small spinules 

 (Figure 629, C), 3—5 at basal margin. 

 Tibia short, narrow basally, strongly curved, wide distally, with large 

 distoventral process, slightly more than /a as long as femur; dorsal setae 

 forming a subapical pair, dorsal seta thin, moderately long, light, directed 

 upward, subdorsal seta thicker, situated slightly posteriorly and directed 

 distally; setae of 2nd dorsal pair situated about in the middle of the tibia, 

 dorsal seta thin, subdorsal (situated anteriorly and slightly basally) larger 

 and thicker; posterior distoventral seta in form of large, thick, moderately 

 long spine on the process; anterior distoventral seta situated basally, short, 

 in form of a light spine; a dense row of light spinules between setae, at the 

 margin, those near basal margin smaller; distal spine (near the process) 

 larger than others, another similar spine near distoventral seta; 5 small 

 spinules situated basal to primary basal seta at dorsal margin of the process. 



Tarsus thinner than tibia; dorsal setae light, distal seta short, the 

 2nd slightly larger, situated in basal part; distoventral setae represented 

 by spines, posterior thin, yellowish, anterior light, shorter, and thicker, with 

 3—4 small spinules basally; a regular row of small spinules at ventral 

 margin, a small, light, spine- shaped seta further basally. 



Claw reddish brown, long, thin, slightly longer than tarsus, basal seta in 

 form of thin, pointed, light spine. 



Hind legs (Figure 629, D) resembling midlegs. Coxa slightly longer, its 

 basal part with 2—3 large, tooth-shaped processes, and 5—7 smaller 

 processes subdorsally. Basodorsal seta reddish brown, strong, moderately 

 long; anterior apical dorsal seta brown, shorter; 5—6 short, light brown, 

 secondary setae situated at margin among the preceding two; posterior 

 apical dorsal seta brown, moderately long, thin; 4 light brown, secondary 

 setae, 2 long, 2 shorter, further distally at margin; basal part with 4 large, 

 thin, brown, secondary setae near processes; 2 similar subventral setae 



469 



