13. DIOCTRIA 747 



five rather small dorsal bristly hairs and two anterior (one at a third from 

 the base small, and the other at two-thirds mncli lonf;-er) ; hind femora with 

 one or two anterior bristles before the middle which are short but rather 

 strong ; several long thin hairs occur beneath the basal half of the middle 

 femora, and a few beneath the other femora ; the furry pubescence on the 

 hind femora and tibiic pale yellow. Pulvilli orange ; claws orange with just 

 the tip black. 



Wings very slightly greyish or rarely brownish, but yellowish at the base 

 and on the subcostal vein. Alar squamte pale yellow with a slight pale 

 yellow marginal fringe. Halteres yellow. 



9 . Very much like the male. Head with the postocular silvery band extending 

 a little more upwards. 



Thorax with the middle line of tomentum rather broader. 



Abdomen varying in the amount of the orange markings, which are 

 frequently limited to triangular lateral spots, though sometimes the terminal 

 segments have broader orange hindmargins. Genitalia orange and orange 

 haired beneath. 



Legs inclined to be less darkened, so that the hind femora and tibial may 

 have only indistinct brownish markings and the tarsi be hardly darkened 

 dorsally, though sometimes the legs are as dark as in the male. 



Wings sometimes a little brownish. 



Length about 9-5 mm. 



This species is not really closely allied to any other and can be readily 

 recognised if care be taken to observe the brilliantly shining thoracic 

 stripes and markings, and the yellow coxae and yellowish anterior tarsi. 

 It varies considerably in the amount of reddish orange markings on the 

 abdomen and slightly in the darkening of the hind legs and all the tarsi. 



D. linearis is not at all uncommon in the New Forest, but otherwise I 

 have only seen it from several localities in Sussex and Kent, though I 

 have records from Somerset, Leicestershire (Market Bosworth), Hereford- 

 shire, and Notts, and Mr C. Morley says it is not uncommon locally 

 in Suffolk, at Assington Thicks. My captures have all been made between 

 June 11 and July 11, though I beheve I have seen specimens which 

 were taken in August. It is recorded from South Sweden through all 

 Central to South Europe. 



Synonymy.— M\ the English references to D. flavi2oes may without doubt be 

 referred to D. linearis, as it is almost certain that the trtie Z>. hyalipennis 

 (=flavipes) does not occiu- so far west except in its (possible) form D. Baumhaueri. 

 Walker's description of his D. flavvpes also obviously applies only to D. linparis. 

 A few specimens of I), linearis occtirred in Bigot's collection mixed tip with D. 

 flavipes, but other specimens under the name of D. linearis were correctly identified. 



