CCENOMYINiE 259 



CCENOMYINiE. 



Antennte with the third joint flagelliform and anniilated. Face 

 socketed. Legs with all the tibiae spurred. Wings with a loner bell- 

 mouthed cubital fork which includes the wing-tip. 



Face socketed ahnost as in the Leptince. Palpi long, thin, porrect, and pointed 

 indistinctly composed of two almost equal joints. Eyes hairy {Coenomyia) or bare' 

 touching in the male. Antennai (fig. 168) with the third joint flagelliform and 

 8-annulated ; the last annulation forming a stout terminal style without any arista. 



Thorax bearing only short pubescence or almost bare ; metapleurje and the back 

 part of the mesopleuras with dense tufts of pubescence, which is longer in the 

 male than in the female, but otherwise the pleura bear very slight pubescence. 

 Scutellum armed with two short subapical spines {Ccemmyia) or unarmed. 



Abdomen rather large, and bearing only minute pubescence. Genitalia of the 

 male small ; ovipositor short and not telescopic, ending in two small oval lamellae 



Legs moderately strong, almost bare ; coxaj only moderately long ; all the 

 tibi^ spurred, one spur on the front the pair, two on each of posterior pairs. 



Wings with a rather 

 peculiar venation, in at any 

 rate the genus CmiK/nitjia 

 (fig. 1 86). Cubital fork long 

 and beli-mouthed, Avith the 

 upper branch before, and 

 the lower one after, the 

 wing-tip ; basal cells long, 

 reaching to fully half the 

 length of the wing ; ambi- t, ,.. ^ 



ent vein complete; alula Fm. 186.-Ca«om,ta /err«,,nm 



well developed ; wing- 

 membrane glittering in Coenomyia, not smooth but hardly ribbed or rippled, and 

 with only a microscopical pubescence. 

 Not at all Ichneumon-WkQ flies. 



The Cmnomyhuc and Xyloijhagincc are the only Le,j)tidai with an 

 obviously annulated antennal flagellum ; the Xylophafjince are dis- 

 tinguished by their marked Ichneumon-like appearance, the separated 

 eyes of the male, and by the cubital fork being triangularly wide open 

 with the lower branch ending in the wing-tip. Only one genus of 

 Ccenomyina: {Ccenomyid) containing a single species is known in Europe, 

 though two other genera with a single species each are recorded from 

 Siberia; the European species, Ccenomyia ferruginea, is widely spread 

 over nearly all Europe, even to the Netherlands and the North of France, 

 and also occurs commonly in North America, but has never been even 

 reputed to have been caught in England. There is a remarkably strong 

 scent arising from this fly, which is most persistent and may be noticed 

 after many years whenever a box containing specimens is opened. 



Synonymy. — There can be no doubt that Latreille's original name for the genus 

 was Ccenomyia with a diphthong, but it is quite true that he afterwards sometimes 

 used Caenomyia. In the Precis (1796) the diphthong ce was often used, as in 

 Phalama, etc., and as there is no obvious error in the original name, while the only 

 derivation which I can find given about that time is " mouche a boue ''' in the 

 Encyclopedie Methodique, I prefer to retain the original spelling. The genus 

 Ccenura appears to me to belong to the Pangonince, as the cubital fork is of the 

 true Tahanus shape, and the squamae bear long dense pubescence, but the small 

 antennae have a terminal arista and the ovipositor is long and apparently telescopic ; 

 it also has the small cross- vein distinctly present, but this character almost occurs 

 in the Coenomyidous genus Arthropeas. 



