2 Of) [March 



witli the exception of having a naked arista ; and a third, which is 

 yery common, is so similar to an Antltomyia, except in its hairy eyes, 

 that it has been named by Eondani L. anthomyinus. 



Ophtra. — The typical species in this small genus (O. leucostoma) 

 is characterised by the curved hind legs, dark metallic blue-black oval 

 body, naked arista and eyes. 



LiMiv^OPHOEA. — This genus is so closely related to Spilogaster, that 

 it is rather difficult to define the limits between them. Thus Schiner 

 includes in Limnophora all those species with spotted oval or oblong 

 bodies, and naked eyes, which have a short haired arista. Eondani, 

 on the contrary, restricts it to those only which have quite, or nearly 

 quite a naked arista, and, at the same time, have the tibiae of the mid- 

 dle pair of legs furnished with one or more setse or short bristles on 

 the middle of their external as well as posterior surfaces, in addition 

 to the usual apical ones. He thus contracts the genus within very 

 narrow limits, and I think it better to do so, as we can then define it 

 accurately ; for it is found that in all the spotted species with a plu- 

 mose arista, whether long or short haired,forming the genus Spilogaster 

 proper, the middle tibiae have no bristles on their external surfaces. 

 In this and the two preceding genera there are six thoracic bristles. 



HoiiALOMTiA. — This is one of the best defined and most natural 

 genera in the family. The species may be recognised at once by 

 having a smooth semi-circular head, without any projecting angles, 

 and by the eyes being very large and extending much lower over the 

 face than in the species of other genera, so as to cover the cheeks. 

 The alulets are small, but the lower scale is not quite covered by the 

 upper one. The abdomen is rather elliptical and flattened, and is very 

 commonly figured on the dorsum in the males, with a central line of 

 triangular marks. The shortness of the anal vein of the wings, with 

 the curving of the axillary vein towards it extremity, is very character- 

 istic of this and the following genus. 



The males of these common little flies, the best known of which 

 are H. caniciiJans and S. scalaris, are often seen sporting in troops 

 in the air in summer, performing aerial dances after the manner of 

 the Tipididce. 



AzELiA. — This small genus, named Atomogaster by Macquart, 

 may be known at once from Somalomyia by the species being of a 

 velvety-black colour in the males, and having a narrow cylindrical 

 abdomen marked by three rows of dots, which are so arranged as to 

 form a series of trianjiles. 



