on segment 1. Subapical spurs of the hind tibiae inflated like vesicles, 

 posterior spur larger than the anterior. Claws small and rudimentary. 



Gills present on abdominal segments 2—7; gill of segment 2 consisting 

 of one dorsal filament, gills of segments 3—6 of 2 filaments; ventral filament 

 normally developed on segment 7; dorsal filament very small. Plates of 

 holding apparatus light brown, presegmental plates present on segments 3—8, 

 postsegmental plates on segment 5; spinules thin; their numbers as 

 follows: 111:3-5; IV:5-7; V:4-7+9-ll; VI:8-11; VII:5-7; VIII:2-5. 



Abdominal segment 9 of male and female pupae with 2 dorsal lobes with 

 numerous stiff setae; male pupae with ventral rudiments of genitalia and 

 broad penis sheath. 



Pupae lying in a case (Figure 614) attached to stones or pieces of wood; 

 wall of case thick, covered with small stones or detritus; length of case 

 17.5— 24.0 mm. The pupa lies in a cocoon attached to the walls at the 

 429 anterior and posterior ends. A horizontal slit about 2.5 mm wide and 

 protected by small stones near the anterior and posterior end. The 

 openings are cleaned with the setae of the labrum and anal legs. 



Mode of life and habitats. Small brooks and rivulets with 

 moderately strong current; often on moss, in spring brooks; if the larvae 

 live in rapid streams, they occur under stones, or in concealed places where 

 the current is slow. 



Distribution. West, northwest and in the central belt of the 

 European USSR. In addition, Europe. 



2. Plectrocnemia latissima Martynov 



Martynov, 1926a:32-33. - Lepneva, 1940:83, Figure 2.* 



Full-grown larva. Length 22—24 mm. Form of body as in P. con- 

 s p e r s a; width of head 2.4 mm. Main color of head brownish yellow; 

 eyes small (Figure 615), situated on a whitish yellow background. Elliptical 

 light figure on frontoclypeus indistinct, sometimes divided. Punctate figure 

 in middle of sclerite oblong longitudinally, open anteriorly; posterior arc 

 of figure consisting of 6 large dots, 2 median dots larger than the others; 

 dots irregularly elliptical, with dark borders; anterior branches of figure 

 consisting of 4 small dots. Short, oblique rows of 3 large dots near the 

 anterior margin of the sclerite; one dot in the anterior angle of the sclerite 

 and anterior to the middle frontal seta. 



Dorsal stripes reddish brown, closely adjacent to the frontal sutures and 

 to the anterior part of the coronal suture; stripes broad posteriorly, with 

 large dark dots; outer margin of the stripes, especially in light specimens, 

 indistinct; small dots near the occipital foramen. Lateral stripes broad, 

 with numerous small dots and a few large dots; outer margins of stripes 

 distinct. Ventral surface yellow or light yellow laterally; broadly brownish 

 or reddish brown in the middle; rows of dots, which are arranged obliquely 

 or like a wedge posteriorly (Figure 615, B). Setae as in P. conspersa. 



Broad longitudinal stripes of anteclypeus yellowish; spaces between 

 them narrow and light. Labrum (Figure 616) very short, broad; dorsal 

 sclerite brownish; anterior margin with narrow reddish brown borders that 

 are wider at the margin of the median depression; posterior angles of 



* See footnote on p. 101. 



484 



