THE MYCETOPHILIDA. 133 | 
B. dubia, Staeg. 
This is a black gnat. Head and thorax covered by a gray tomen- 
tum ; antennz slender, 16-jointed and a little longer than the thorax. 
The abdomen is long and dark. Wings have the fork of the fifth 
longitudinal vein nearer to the base of wing than the fork of the fourth 
longitudinal vein ; sixth extends nearly to the fork of the fifth. Legs 
testaceous, long and slender ; tibiz dark, posterior tibia with long 
spurs and short spines: tarsi black. Length 3 to 34 lin. 
Mycetophila sciarina, Mg. 
M. obscurella, Zett. 
This is a blackish-brown species, very widely distributed. Zetterstedt 
describes it from Norway, etc., under the name odscure/la. It is, 
according to Walker, slightly covered by a gray tomentum. Palpi 
and antennz are blackish-brown; the antennze are twice the 
length of the thorax. The body is clothed with yellowish hairs. The 
anal segment is longer than the one before it. The legs are testa- 
ceous, and the spurs short ; tarsi blackish-brown, and the hind tibiz 
with very few short spines. The wings have a grayish tinge ; second 
and third longitudinal veins very distinct, brown ; the fourth and fifth 
pale ; the sixth fairly long, extending beyond the fork of the fifth. 
B. stiarina, Staeg. = \ 
‘Length 14 to 2 lin. 
The other British species are ¢rivittata,* Mg. (System. Beschr. i., 
258, 10); dorealis, Zett. (Dipt. Scand., xi. 4,160, 8); plana, Wk. 
(Ins. Brit., vol. iii., p. 34) ; analis, Mg. (System. Beschr., i., 257, 9). 
GENUS Leptomorphus, Curtis. 
This genus was formed by Curtis, one species only being known. 
The body is slender ; head small ; palpi 4-jointed, long and slender, 
Fic. 26.—Head of Leptomorphus Walkeri. 
fourth joint longest. Eyes oval; ocelli two. Antenne 16-jointed, 
filiform, about half length of body. Thorax very short. Abdomen 
compressed, thickened at the tip; the hypopygium large. Legs long 
and slender, very small spines to tibize and very long spurs. Wings 
narrow, hairy ; costal ends a little in front of tip of wing ; first longi- 
tudinal vein long, connected with the second by a transverse veinlet 
* Taken at Linton, Ivybridge, Loch Maree and Tongue, in June. (Verrall.) 
