566 Mr. Kenneth J. Morton on 
long and narrow; the lateral appendages of about the ordinary 
length, tapering slightly to the apex, which is obtuse and appa- 
rently simple. Exp., ¢,15 mm.; ¢, 20 mm. 
The brownish aspect of this fly is a good prima facie 
character for its determination; the weak neuration and 
the form of the lateral appendages are also of impor- 
tance. All the examples are from Dr. Ris, and are 
labelled “ Oerlikon, April.’ A species requiring further 
elucidation, but I think it is a good one. Confusion 
especially in the @ sex is likely to take place with the 
species 1 here name N. marginata, but the characters of 
the ¢ appear to be decisive. 
Nemoura prxcow, n. sp. 
Phryganea_ regelationis, Scop., Ent. Carniolica, 
ps 209 (ce 
Head and thorax black, antennze concolorous; pronotum 
broader than the head without the eyes, short, borders not well 
defined in the dry insect, lateral margins usually with a slight 
angulation about their middle part, behind which they recede 
somewhat. Legs: femora above, ends of tibiz and the tarsi 
blackish fuscous. Wings greyish, sometimes fuliginous, neuration 
blackish fuscous ; all the veins margined more or less with darker 
cloudings, which are most distinct about the pterostigma and 
x veins. The anal structure of the ¢ is complicated: the lobe of 
the ventral plate is of great size. What appears to correspond 
with the long spinous sheath of N. A/eyeri consists here of a broad 
basal part with a very short spine. Exp, ¢, 18 mm.; 
©, 20-23 mm. 
The complicated anal structure of the ¢ and the some- 
what fuligimous aspect of the wings should make this 
insect recognisable. The form of the prothorax above 
alluded to is constant in the British examples which I 
have examined. 
Apparently not rare in Great Britain. It occurs in 
early March (if not earlier in mild seasons) by the River 
Clyde and one of its affluents, along with Teniopterye 
nebulosa and 1’. trifasciata. I have also seen both sexes 
from Perthshire rivers in April (King), and two ?s are 
in Mr. McLachlan’s collection from the Manchester 
district in March (Cooke). 
