THE MYCETOPHILID.E. 137 



The round head and circular eyes, the ocelli being nearly equal 

 and in a curved line, and the cylindrical joints of the antenna, be- 

 sides the veins, at once distinguish this genus. 



Genus. — Lasiosoma, Wtz. = Sciophila, Mg. 



The larva; of this genus live in fungi and rotten wood. The 

 gnats may be found in woods and thickets. The genus may 

 be distinguished by the base of the fourth hind areolet being 

 much further from the base of the wing than is the base of the 

 second hind areolet. It is nearly allied to Sciophila, but the costal 

 does not extend to the tip of the wing as it does in Sciophila. 

 There are seven species of this genus found in Clreat Britain. 



r 1 ■ . AT f -5". hirta, Hoffm. 

 L. Iiirtum, Mg. = _, . ' „ 



\S. puosiila, Zett. 



Blackish-brown. Head brown. Pal[)i testaceous ; antenna longer 

 than thorax. Abdomen brown. Legs yellow ; tarsi brown, yellow 

 at the base ; posterior femora dark at the base and tips ; posterior 

 tibiae also dark at the tips. 



Wings with a brownish-gray tinge ; first cubital areolet of moderate 

 size, oblong. This is a fairly abundant species. Length i^ to 2 lin. 



L. riifilateni/n, Wlk. = S. riifilakra, Wlk. 



This is a dark brown insect ; palpi yellowish ; antenna; blackish- 

 brown, tawny at the base. Thorax with a tawny spot on each side 

 in front. Abdoniu ^ tawny on each side, except towards the lip. 

 Legs tawny ; tarsi brown ; posterior tibia; with minute spines and 

 rather long spurs. Wings grayish. First cubital areolet very small, 

 almost square. Length if lin. Scarce species. 



The following are the other British species : 



L. luteum, Macq. Dale has bred this species from larvae feeding 

 in a web on a fungus on a pear tree. The imago is yellowish, with 

 dark brown head. 



L. ochracet-cjii, Wlk., Ins. Brit. Dip., vol. iii., p. 41. L. iiiaura, 

 Wlk., ibid. p. 42. L. feneslrella, Curtis, British Ent., 641 (1S37). 

 L. rufiim, Mg. 



Genus. — Monoc/ona, INIik. 

 M. halter at a, Staeg. 



This is a rare species, resembling S. (Z.) nifuni, Mg., in appear- 

 ance. The imago is testaceous ; the head has front and vertex dark- 

 Thorax blackish-gray, beset with long whitish-yellow hairs. Areolet minute. 

 Abdomen as in hirta. Sub-costal obsolete. 



Melanoccras— hx^\.^x\v\'ss. quite black. Sub-costal complete. Areolet elongated 

 and dilated at the tip. Holywood, near Belfast (Haliday). 



