130 Mr. F. Walker's Characters of undescrihed Diptera 



Genus Asilus, Linn. 



AsUus ser'icans. 



Fccm. — Cinereus, capita cano, fronte subaurata, mystace albido 



supra nigro, antennis nigris, thorace vittis quatuor nigris, 



pectore cano, abdomine nigro oblanceolato, basi lateribus- 



que cinereis, apice compresso nitente, pedibus ferrugineis, 



coxis femoribusque nigris, alis subluridis. 



Female. — Cinereous ; head hoary ; front very slightly gilded ; 



mystax composed of some whitish shining bristles, above which 



there are a few more slender black bristles ; proboscis and 



antennae black, seta of the latter longer than the third joint ; 



thorax with four distinct black bands ; pectus hoary ; abdomen 



black, oblanceolate, cinereous at the base and along each side ; 



tips compressed, shining ; legs ferruginous, with black spines and 



hairs ; coxae and femora black ; wings slightly lurid ; veins 



black. 



Length of the body 5 lines ; of the wings 8 lines. 

 Amazon region. 



Asilus firmatus. 



Fcem. — Cinereus, capite aurato subtus albido-hirto, mystace 

 nigro supra testaceo, antennis nigris, thorace vittis quatuor 

 nigris abbreviatis, abdomine maculis trigonis fuscescentibus, 

 apice nigro subcompresso, pedibus nigris, femoribus supra 

 tarsisque basi ferrugineis, tibiis fulvis, alis cinereis, areolis 

 posticis luridis cinereo-strigatis, venis nigris, halteribus fulvis. 

 Female, — Cinereous ; head with pale gilded tomentum, clothed 

 beneath with whitish hairs; mystax with black hairs towards the an- 

 tenna, and with pale testaceous bristles towards the proboscis ; 

 antennae black, arista not longer than the third joint ; thorax with 

 four short black stripes ; abdomen with a triangular brownish spot 

 on each segment, tip black, slightly compressed ; legs black, 

 femora ferruginous above, tibiae tawny, tarsi ferruginous at the 

 base ; wings grey, lurid hindward, with a grey streak on the disk 

 of each areolet ; veins black; halteres tawny. 



Length of the body 10 lines ; of the wings 14 lines. 

 Port Natal. 



Asilus mendax. 



Mas. — Ater, nigro-setosus, capite subtus cano-piloso, facie au- 

 ratA, mystace nigro, tibiis tarsisque subtus fulvo-pubescenti- 



I 

 1 



