Notes on the Ephemeridce. 399 
paler (and so far as I can remember, all specimens caught 
late in the night are not so dark in colour), but the fore 
femora are darker. 
Two males caught at Neuhausen, not far from Pillau, 
Avere sent to me by Prof. Zaddach as lumiyious insects. 
He had seen them in the night giving a small blue light. 
[My own observations ol" the moulting of the subimago 
quite tally with Dr. Hagen's. I have likewise failed to 
find the pupa-skin on the water out of doors. But I 
found that the specimens which I reared in the house in 
flower-pot saucers, changed from nymph to subimago at 
the surface of the water, and left the empty pupa-skin 
afloat, just as Baetis or Ephemera does. I had intended 
to describe the visual organs in some future part of my 
work when treating of the comparative anatomy of the 
Ephemeridce. Perhaps I may never have time to do this. 
In my descriptions I have indicated that the central seta 
is not invariably the longest.] 
Page 96. Ccenis discolor. My type was labelled 
" albida" in Winthem's collection ; but it is closely con- 
formable with Burmeister's description. It has unusually 
long wings, and perhaps represents a new genus. Habitat. 
Caffraria. 
Page 97. Ccenis luctuosa. My collection contains 
specimens from England, Germany and St. Petersburg. 
I think Ccenis to be more nearly related to the old 
Palingenia, Oligoneuria, &c., than to the genera with 
which you class it. 
[I have stated some of my grounds for considering 
Ccenis to be closely allied to Leptophlehia i-ather than to 
Palingenia. In my paper on the nymph of Ccenis (Etn. 
1868) I also stated my belief that Oligoneuria will be 
found to be very nearly related to Ccenis ; but without 
knowing the nymph I decided not to remove that genus 
from the neighbourhood of the old Palingeiiia.^ 
Page 102. Cloeon dipterum. Larva yellowish-brown, 
the head a little darker, eyes black ; thorax with a dark 
spot on each side, legs pale ; as far as the middle of the 
caudal sette the joints have dark basal rings and are hairy. 
Length 7mm. 
Nymph (winged) or pupa. The abdominal segments, 
TRANS. ENT. SOC. 1873. — PART III. (AUG.) F F 
