DIPTERA 



833 



one edge of each segment is prolonged so that the antennas are pecti- 

 nate (Fig. 1067). Four species of this genus have been found in America 

 north of Mexico. 



The larva of Rhachicerus mtidus has been foimd in a decayed log. 



Family XYLOPHAGID^ 



This family, like the preceding one, includes slender flies, which 

 are Ichneimion-like in appearance. It is distinguished frorn other 

 Anomalous Brachycera as follows: from the Stratomyiidce in that 

 the branches of radius are not crowded together near the costal border 

 of the wing (Fig. 1068) and in the possession of tibial spurs; from the 



/?. /?2+j 



Fig. 1069.- 

 r-,. _L ov zj """ Antenna 



of Xylo- 



Fie. 1068.— Win? of Xylophagus, phagus 



and, p, 

 palpus. 



Xylomyiidse in that cell M3 is open ; and from the Coenomyiidse in the 

 absence of spinous protuberances on the scutellum. The flagellum of 

 the antennse consists of several closely consolidated segments; the 

 antenna of a member of the typical genus is represented in Figure 

 1069. 



This family is represented in our fauna by the following genera: 



Fig. 1070. — Wing of Ccenomyia ferruginea. (After Verrall.) 



Xylophagus, Glutops, Arthoceras, Arthropeas, and Misgomyia. These 

 genera include sixteen species described from our fauna. 



