22 



which it differs by the paler colour of thorax and tibiae 

 and by the strongly curved anal veins. I have in my 

 collection a Spanish specimen of the species, received 

 under the name Habrophlebia fusca Curt. 



2. Habrophlebia modesta Hag. (Potomanthus modestus 



Hagen, Ann. Soc. Ent. Franc. 1864, pag. 39). In the col- 

 lections of Budtz there were three males and one fe- 

 male, all imagines. The species is very easely recogniz- 

 able by the strong yellowish tinge on the wings, espe- 

 cially along the front margin of the fore wings. Also 

 the pitchy brown veins and its greater size are good spe- 

 cific characters. The costal area of fore wing contains 

 about 11 — 13 well defined cross veins before the ptero- 

 stigmatic space, while this contains about 10 — 12. 



3. Habrophlebia nervulosa Eaton (A revision. Monogr. of 



recent Ephemeridae or Mayflies, 1883 — 88, pag. 117). 

 Of this species hitherto only found in Portugal there is 

 a long series. Although it is no easy matter to deter- 

 mine dried specimens of Habrophlebia, because the co- 

 lours are liable to vary greatly with the direction, in 

 which they are held to the light, what also Eaton has 

 stated, I refer the specimens to this species. A good 

 character, I think, may be found in the shape and nervation 

 of hind wing, and of course also in the shape of anal 

 appendages of the male. 



4. Baetis pumilus Burm. A large series of males and a 



few females. 



5. Baetis binoculatus Linn. A few specimens. 



6. Ephemerella ignita Poda. Several specimens. 



7. Rhithrogena eatoni Peters. (Ent. Medd. København, 



1912, pag. 352). Of this species there was present a fine 

 lot. It is the smallest known species of the genus. 



8. Rhithrogena insularis n. sp. S (dried). Thorax brow- 



nish black with some yellowish brown spots on the sides 

 (in some specimens the colour of thorax is castaneous 

 brown). The abdominal segments dorsally brown (with 



