with a large dorsal denticle; seta 1 short, seta 2 longer; basomedial seta 4 

 small; ventral seta 8 light and curved; seta 7 dark and thinner. 



Mode of life and habitats. Cold-water rivulets with stony 

 bottom. 



Distribution. USSR: Caucasus. 



308 



2. Glossosoma vernale Pictet 



Pictet, 1834:190, Plate XV, Figure 4, a, c. - Hagen, 1864:143.- Siltala, 

 1905:152-153, Figure 40.- Ulmer, 1909:222, 290.- Lestage, 1921:423-426, 

 Figure 135, g. 



Full-grown larva. Length 8— 9 mm. Head yellowish brown. Fronto- 

 clypeus (Figure 366) darker anteriorly than posteriorly; its posterior part 

 with distinct light dots; light, darkly rimmed dots lateral to the coronal 

 suture and at the beginning of the frontal sutures. 



Median brush of mandibles as in G. unguiculatum; left mandible with 

 a brush of simple chetoids and several long feathered chetoids; right 

 mandible with only feathered chetoids. 



Pronotum yellowish brown, with indistinct dots. Legs without dots. 



FIGURES 366-369. Glossosoma vernale Pict. (after Siltala): 



366 - frontoclypeus; 367 - labrum and anteclypeus of pupa; 368 - left mandible 

 of pupa, dorsal; 369 — end of body of male pupa. 



Pupa. Length about 7 mm. Antennae of female pupa reaching to the 

 anterior margin of abdominal segment 6. Three setae on each side of the 

 clypeus; setae almost equally long; anterior margin of labrum with a shallow 

 median notch; labrum with 6 setae, anterior median seta much smaller than 

 the others (Figure 367). Mandibles (Figure 368) as in other species of 

 Glossosomatinae, serrate in the middle; basal tooth small; outer setae small, 

 situated close together, equally long. 



Number of spinules of holding apparatus: 111:14—16; IV: 17— 22+ 33-44; 

 V.-16-26+ 31-42; VL12-20; VIL14-40; the sides of segments 8 and 9 with 

 tubercles covered with spinules near the posterior margin. 



Posterior end of body narrow, curved ventrally in males (Figure 369) and 

 in females; lobes each with 3 setae. 



Pupal case 8—12 mm long and 6— 8 mm broad, built of small stones; 

 cocoon yellowish brown. 



335 



