Abdominal segment 1 as in B. subnubilus, without dorsal tubercle; 

 lateral tubercles indistinct. Lateral line thin, on segments 3 — 7, with sparse, 

 brown hairs; several sclerotized dots in anterior- part of each segment 

 dorsal to lateral line. Gills postsegmental (almost intersegmental), on 

 segments 2—7. 



Tergite of abdominal segment 9 short, transverse, rounded postei-iorly, 

 with numerous setae. 



Sclerite "b" of anal legs with black, distal setae, including 3 doi-sal setae 

 largei- than others. Claw with 2 lai-ge, dorsal denticles. 



Case tetrahedral, 12 — 13 mm long, made of small, transversely arranged 

 pieces of detritus; posterior opening with a thin mem.brane bulging outside, 

 and with a lai-ge I'ound hole. 



Pupa. Length of male pupae 7.2—7.5 mm, of female 8.0—8.5 mm.. 

 Antennae of male pupae reaching end of body, those of female, segment 8; 

 scape of antenna slightly longer and thicker than following segments. 



Otfc^cS 



632 



d c 



633 



FIGURES 632 and 633. Brachycentrus montanus 

 Klap.: 



632 — right mandible, ventral; pupa: 633 — postseg- 

 mental row of hooks on segment 5 (A); posterior end 

 of male lateral (B); membrane at anterior end of case 

 (C) (633, A — after Thienemann; others afier Klapalek). 



Labrum as in B. s u b n u b i 1 u s. Mandibles shorter and wider distally 

 than in B. s u b n ub i 1 u s, with serrated median side; lateral setae situated 

 basally, yellowish brown, about equal in size. 



Wing sheaths wide, pointed, anterioi- sheaths reaching end of segment 6, 

 posterior sheaths shorter. Mid-tibia and tarsus with dense natatorial setae; 

 forelegs with spai-se natatorial setae. 



Abdominal segment 1 with blackish brown elevations covered with spinules 

 laterally at posterior margin; holding apparatus on segments 3—7; pi-e- 

 segmental plates with hooks as follows: 111:5-8; IV:6-10; V:5-10; VI:7-10; 



473 



