EPHEMERIDA. 
9 
9. VIII. 09 № 89, at the Talota river; 3. VIII. 09 № 93, at the tundra of Kara; 
20 . VIII. 09 № 274, on the Pyderata river; 27. VIII. 09 J\l?. 69 on the Stschutschja river. 
The nymph is readily recognized by its very long trachéal gills, and it is quite prob¬ 
able that it belougs to Baëtis vernus Curt. 
Baëtis sp. II. 
Nymph. Regarding the shape of the mouthparts it is much like Baëtis I, but it differs 
from it by its shorter trachéal gills. Greyish. Head and thorax with a fine, pale median 
line. Theborders of the abdominal segments — as a rule also those of the venter — darker. 
Middle seta considerably shorter than the two others. Length4,5—5,5 mm.; setae 3,5 mm. 
Fig. 11. Baëtis larva I. Trachéal gills. a 7th gill, 
b 4th gill, c Ist gill. 
Fig. 12. Baëtis larva IL Trachéal gills. 
a 7th gill, b 4th gill, c Ist gill. 
Several specimens present. 
7. VII. 09. № 212, near mount Minisej; 9. VIII. 09 № 89, on the Talota river. 
Sparrea norvegica E.-Peters. 
As Bengtsson has described the larva, I only give a short description. 
Nymph. Parallel sided. Head a little narrower than mesothorax. Upperside light 
brown, underside paler. Round the eyes a pale ring. 
Overside of thorax and abdomen with several pale spots. 
Зап. Физ.-Мат. Отд, 
2 
