tibia of midlegs strong and dark, that of the hind leg spinelike, close to the 

 ventral setae; posterior seta spinelike, shorter than anterior seta, that on the 

 hind legs situated near the ventral setae; posterior seta spinelike, shorter 

 than the anterior seta; seta on hind legs situated near the ventral setae. 

 Two massive primary setae ventrally at the apex which form thick, long, 

 dark spines; anterior seta slightly longer than posterior seta. 



FIGURES 630 and 631. Po ly c e n t r opu s flavomacula- 

 tus Pict.: 



630 — distal part of left hind leg, anterior; 631 - claw of fore- 

 leg of 2nd -stage larva (after Siltala). 



Mid-tarsus shorter than hind tarsus (Figure 630); tarsi of both legs with 

 microscopic spinules; ventral side of tarsus with a small comb of spinules; 

 tarsus with flat chetoids feathered at the apex which are less numerous than 

 on the forelegs. Dorsodistal seta small, dark, slightly curved, recumbent; 

 other 4 setae of the dorsal margin thin; anterior surface with thin secondary 

 setae; ventral primary setae brownish yellow, thick, spinelike, thinly 

 438 feathered, situated far subapically lateral to the comb. 



Claw as on forelegs, thin and slightly curved, with small spinules at the 

 base. A large spine near the seta in larvae of the 1st and 2nd stages 

 (Figure 631). 



Abdomen uniformly broad in its greater part; segment 1 shorter and 

 slightly narrower than the following segments; segment 4 narrow. Dorsal 

 side of abdomen with delicate white pattern consisting of a longitudinal 

 stripe, a narrow lateral stripe and two oblique stripes in each half of the 

 segment. Anterior-margin seta of segments 1 — 6 light and small, slightly 

 larger on segments 7 and 8; Anterior- angle seta of segment 1 small; it 

 increases in size from segment 2 onward and is situated about the middle of 

 the segment; it is situated posteriorly on segments 7 and 8; medioanal seta 

 of segments 2 and 3 small, that of segments 4—8 large, situated near posterior 

 margin; a small intermediate seta and a small lateral seta near it. Setae 

 of pleural region of segment 1 two in number, situated behind each other; 

 segments 2—8 with the primary setae and with a row of long, thin secondary 

 setae that form a longitudinal lateral row (spurious lateral line); one of the 

 ventral setae long on segments 1—8. 



Only the medioanal seta of segment 9 long; anterior -angle seta much 

 smaller, thin, situated in the same row; intermediate and lateral seta very 



495 



