'546 



Antennae reaching middle of segment 9 or slightly further; basal 

 segment of antenna of male pupa with a tuft of thin, dense setae projecting 

 inward. 



Wing sheaths reaching to middle or posterior margin of segment 7; 

 segments 1—4 of mid-tarsi with dense natatorial setae (about 130 on 

 proximal segment,'; fore tarsi with sparse natatorial setae on segments 1—3 

 (about 5 setae per segment). 



First abdominal segment laterally Avith blackish brown, transverse 

 tubercles forming a dark ridge; dorsal sclerites of following segments 

 large yellowish brown, with black margin and large, slightly curved, 

 brown, hook-shaped spines; number of hooks: segment 11:2 — 3; segment III: 

 2+2—4; segment IV: 2; segment \':2 — 3. Segments 9 and 10 partly 

 sclerotized. with small, rounded, brownish tubercles. 



Gills on segments 2—8; gills of segments 4—7 short, relatively thick, 

 on ventral side only on segment 8. 



Lateral line on segments 5 — 8. Anal rods thin, short, with numerous, 

 large, basal setae; a rov/ of 4—6 large, strong setae, sometimes with 

 2 branches distally on ventral side (Figure 871 ). 



Pupal case (Figure 872) long; anterior end with fine sand grains and 

 small stones at margin, attached to substrate; posterior end as in 

 Figure 872, B; anterior membrane with horizontal slit close to ventral 

 margin, posterior membrane with round, central hole. 



Mode of life and habitats. Brooks near the banks, often among 

 plants, in overflov/s of springs, in calm areas on the bottom, sometimes 

 at the edge among humid fallen leaves or on the lower side of branches 

 of trees. 



Distribution. USSR: not recorded with certainty, but possibly 

 occurring in the southwest. In addition. Europe. 



2. Sericostoma personatum Spence 



Pictet, 1834: 178. Plate XIV. Figure 2.- Kolenati. 1848:90.- Hagen. 

 1864:238. - Klapalek, 1888:25-28, Figure 9. - Ulmer, 1903:79-80. - 

 Siltala, 1905:13-14.- Thienemann, 1905b: 520-522, Figures 7, 29-33. 117.- 

 Ulmer. 1 909 : 280, 321 . - Lestage, 1921 : 923-931. Figures 32 8 a, f, 329 A. 330E. 

 331. - Lepneva. 1940:218. - Hickin, 1951 : 93-96, Figures 1-11.- Jacquemart. 

 1960:5, Figures 16-20.- Brindle, 1964: 196. Figures 1, 3, 10. 



Full-grown larva. Length 1 1 .5-12.0 mm (Figure 873. A). Head 

 (Figure 874, A) chestnut brown dorsally, with large, light spots. Eyes on 

 light background; antennae small, situated near anterior margin. Fronto- 

 clypeus with 3 light, transverse dots in posterior part; larger, transverse 

 dots lateral to posterior branch of frontal sutures, smaller dots near coronal 

 suture; ventral surface light, with large, light, indistinct dots near occipital 

 foramen. Gula fused with large, lateral sclerites, with distinct, dark, 

 anterior part (Figure 874, b). Chaetotaxy as in S. p e d e m on t a n u m; 

 only a few of the setae are shown. 



Labrum, as in S. p e d e m o nt anu m, with rounded anterior angle; median 

 indentation deep; posterior-angle sclerites short, blunt; setae as in 

 S.pedemontanum. 



681 



