THE BRACHYCERA. 353 



length, of a greyish colour, with the antennae banded 

 with black, and the wings broad, deflexed in the form 

 of a roof, and covered with minute hairs. It is found 

 commonly on windows, running about quickly in 

 various directions, and every now and then diver- 

 sifying its movements with a short jumping flight. 

 Another common species of the same genus (Ps. sex- 

 punctata) has the wings prettily spotted with brown. 

 Besides these we have several other species, which, 

 although their title to rank as Diptera can never be 

 mistaken, appear at the first glance, from their robust 

 forms and short antennae, rather to approach the flies 

 of the second suborder than those of the present tribe. 

 The most abundant of these are the species of the 

 genus Bibio, shining black flies with an abundance of 

 hair about the anterior parts of their bodies, which 

 are found commonly upon flowers in the spring. The 

 larvae live, according to some authors, in dung, whilst 

 others describe them as feeding, like those of the 

 Tipula, upon the roots of grasses. The females of 

 some of the species have the legs red, whilst those of 

 their partners are black, and in some cases, the upper 

 parts of the body of the female are red or orange. 



Suborder BRACHYCERA*. 



The insects forming the second suborder of the 

 Diptera may be at once distinguished from those of 

 the preceding group by the structure of the antennae, 

 which always consist apparently of but three joints, 

 generally furnished with a bristle either at the extre- 

 mity, or on the dorsal surface of the third joint. On 

 closer examination, however, the apparent third joint 

 * Gr. brachus, short ; keras, a horn. 



