Mr. F. W. Edwards’ Notes on British Mycetophilidae. 373 
exhibits no other structural differences from Mycetophila, 
though M. semifusca, Mg., is remarkable for the shortness 
of its cubital fork, and approximates more or less to the 
closely allied genus Zygomyia. M. semifusca may eventually 
require a new genus (the name Mycothera unfortunately 
being inapplicable to it if M. dimidiata is excluded), but 
for the present at least it is placed in Mycetophila. 
The following table of the British species of this genus 
may be of use in roughly determining a specimen, but too 
great reliance should not be placed upon it. Several of 
the species can only be properly separated by a micro- 
scopical examination of the male genitalia. A few more 
British species of Mycetophila are certainly still to be 
found. 
1. Wings quite unspotted  .. mM Sa Wigs aecioe Oe ah eee 
Wings with at least a central dark saat yarn git edad BE 
2. Reddish-brown species . . . . =. punctata, Mg. 
Shining black species . .  Uunicolor, var. posticalis, Ldst. 
3. Wings with a central spot only (M. stolida sometimes has a 
small rather faint subapical spot) . . . . . 4& 
Wings with a central spot and other dark markings more 
towards the apex .. con eS 
4. Reddish or brown species, ahora dull. seuaily ened 
lineola, Mg. 
Black species, thorax shining, unstriped. . . . . 5. 
5. Thorax and (usually) abdomen entirely black — wnicolor, Stan. 
Thorax with yellow shoulder patches . . . . . 6. 
6. Yellow patches between wing base and scutellum — stolida, Wlk. 
No such patches present; shoulder patches much smaller 
pumila, Winn. 
7. Wings with a complete but ill-defined dark fascia just beyond 
the middle; cubital fork very short . : semifusca, Mg. 
Wings without such fascia; cubital fork not very short, though 
its base is sometimes rather beyond that of the median. 8. 
8. Subapical wing markings reaching and usually including the 
apex of the first longitudinal vein (R,) . . . .- &Y. 
Subapical wing-fascia entirely distal to the apex of the first 
longitudinal vein. . Ht ae OPEN * 
9. Thorax shining black, eaddinhs in front : re umbrata, Mik. 
Thorax dull (more or less) : : ; ‘ ‘ ; lO: 
MUPeEHOIAS ARINC ~~ 6 ke a MER 05 |) 1 
Thorax ao. blackish, usually w ‘th one ish shoulder 
patches . ail og ot a Ke nilen 
TRANS. ENT. SOC. LOND. 1913. PART IL. '(SEPT.) BB 
