1888.] 11 



3. Ephemera lineata, Eaton : Mon., 71, pi. iv, 7, lb [adult details] ; 



Revis., 63 (1884). 

 The best-marked abdominal segment has six longitudinal, linear, dark dorsal 

 stripes, shorter than the segment ; of these the outer pair of stripes on each side 

 consists of sub-sinuate stripes of almost equal length, pointed at both ends, and 

 much longer than the median pair, which is composed of curved stripes. 



Near Reading. Summer. 



4. Potamanthus luteus, Linne: Mon., 76, pi. ii, 1, and iv, 13, 13a 



[adult details] ; Revis., 79, pi. ix, 14 [adult details], and xxxi 

 [nymph] (1884). 

 The sub-imago is apt to be mistaken for the common Heptagenia sulphured. 

 The forked second axillar nervure of the fore-wing, and the lobed ninth ventral 

 segment, serve to distinguish the female insect from Ephemera. 



Weybridge. Summer. 



5. Leptophlebia marginata, Linne : Mon., 84, pi. ii, 2a, and iv, 25, 25b 



[adult details] ; Revis., 93, pi. xi, 17a [adult details] (1884). 

 Wings of sub-imago grey, spotless. Penis lobes pointed, spurred beneath. 

 Spring and autumn. 



6. Leptophlebia submarginata, Stephens : Revis., 94 (1884), = L. 



helvipes, Cat., p. 7 ; Mon., 85, pi. iv, 26, 26o* [adult details]. 

 Wings of sub-imago grey, pale-spotted in the midst. Penis lobes flanged trans- 

 versely at the tips, spurred beneath. 



Spring and summer. 



7. Leptophlebia cincta, Retz. : Mon., 87, pi. ii, 2c, and iv, 27 [adult 



details] ; Eevis., 95, pi. xxxii [nymph] (1884). 

 Wings of sub-imago black, spotless. Anterior abdominal segments of <J usually 

 transparent white. Penis lobes flanged shortly at the tips transversely, spurred 

 beneath. The sub-imago and adult $ are apt to be mistaken for Baetis pumilus. 



Summer. 



8. Habrophlebia fusca, Curtis : Revis., 116, pi. xiii, 22a [adult details], 



and xxxvi [nymph] (1884),= Leptophlebia fusca, Cat., p. 7; 

 Mon., 90, pi. ii, 2c, and v, 2, 2b [adult details]. 

 Summer. Small streams. 



9. Ephemerella ignita, Poda : Mon., 98, pi. ii, 5, and v, 7, 7a [adult 



details] ; Revis., 126, pi. xiv, 24a [adult details], and xxxvii 

 [nymph] (1884). 

 Penis lobes truncate at the tip before desiccation. 

 Summer and autumn. 



