Dolichopodidae. 5 



labiimi is not long. Thorax rectangular, sometimes almost or quite 

 square; it is somewhat high, and more or less arched above. In some 

 genera the disc has a flat or slightly concave, somewhat declining 

 area behind, in front of the scntellum ; this area is sometimes small 

 and less distinct. Postscutellum distinct, sometimes somewhat long. 

 The præsutural depression is large. Prothorax small; it has a 

 transverse rovv of small bristles above. Metathorax likewise small, 

 but distinct and visible above as a narrow rim; there is no chitinised 

 metasternum. The metaepimera are very distinct, sometimes rather 

 broad; they are generally lying more or less close lowards the ab- 

 domen, sometimes directed more outwards. The acrostichal bristles 

 are generally short or very short, rarely longer; they are biserial or 

 nniserial, in the latter case sometimes irregularly biserial behind, and 

 they are sometimes quite absent; they do not reach to the scu- 

 tellum. The dorsocentral bristles may be of various number in the 

 various genera, and also sometimes in the same genus; they are very 

 often six, but may be more numerous or on the contrary go down 

 to only three or two, in the latter case they are then sometimes 

 continued in front by small hairs; their number is generally, but not 

 always, quite constant in the species; they increase as a rule in length 

 towards behind. Of bristles the thorax has further a humeral, and 

 generally one or some weaker, one or two posthumeral; of the other 

 bristles the number is generally the following: one præsutural, three 

 supraalar, the first placed at the inner end of the transverse furrow, 

 one postalar and two notopleural bristles, but the præsutural bristle 

 may be absent, and likewise one or two of the supraalar, or they 

 may be very small, and sometimes there is only one notopleural 

 bristle.^ The rows of bristles are generally more or less diverging 

 towards behind, especially the last dorsocentral bristle is placed some- 

 what laterally. The front part of the disc, to the transverse furrow 

 behind, has more or fewer small hairs, some of which may some- 

 times be stronger; they are very conveniently termed præscutal hairs 

 (Pråskutalborstchen) by Oldenberg 1. c. The propleura have as a 

 rule hairs, either both above and below, or only below, and they 

 have generally one or several prothoracic bristles. Metapleura have 

 no hairs. In one genus, Eutarsus, the pteropleura are hairy below. 



^ I have here followed the lerminology for the bristles given by Oldenberg (Zeitschr. 

 f. syst. Hymenopt. und Dipt. IV, 1904, 67). The author states that it is in accord- 

 ance with the views of Girschner. Intraalar bristles are thus considered to 

 be wanting. I am however not sure, whether it is perhaps not more correct 

 to consider the two first supraalars as intraalars. 



