DICHAETA. 133 



other are as follows : The species of Dichcela have longer and 

 stouter bristles ; the mystacidal bristles on the side of their face there 

 are less numerous, but much longer and stouter; moreover, in the 

 males of Dichceta the penultimate segment of the abdomen, on its 

 posterior edge, is provided with a transverse row of very long bris- 

 tles, and on the tip of the last segment, above the anal opening, 

 there are two bristles inserted near each other and curved upwards, 

 which is never the case in Noliphila. 



Only two European species of Dichceta were hitherto known. The 

 two species occurring in North America are identical with them. 



Synopsis of the Species. 



( Last segment of the abdomen in the male prolonged in a conical point. 



J 1 caudata Fall. 



I Last segment of the abdomen in the male not prolonged in a conical 



point. 2 brevicauda Loew. 



1. I>. caudata FALL. and 9 Nigricans, seginento abdominali 

 penultimo in mare setis decem elongatis armato segmentoque ultimo in 

 conum producto. 



Blackish, the penultimate segment of the male abdomen with ten long 

 bristles, the last segment couically prolonged. Long. corp. 0.17. Long, 

 al. 0.17. 



This well known species is distinguished from the following by 

 its somewhat larger size, the greater number and the length of the 

 bristles on the posterior border of the penultimate segment of the 

 male abdomen, the conical prolongation of its last segment, and the 

 much greater length of the two stout bristles inserted on the tip 

 of this prolongation. 



Hdb. Middle. States. (Osten-Sacken.) 



Note. A detailed description of this species is to be found in Meigen, 

 Zweifl. VI, p. 62. 0. S. 



2. D. lrevicauda LOEW. . Nigricans, segmento abdominali pe- 

 nultimo in niare setis sex elongatis armato segmentoque ultimo breviter 

 acuminato. 



Blackish, the penultimate segment of the male abdomen with six long bris- 

 tles on the posterior border, the last segment but little pointed. Long, 

 corp. 0.16. Long. al. 0.16. 



The differences pointed out in the description of the foregoing 

 species will be sufficient to distinguish this. The greater part of 



