290 Mr. F. Walker's Characters of undescribed Diptera 



Eristalis familiaris. 



Mas. — Ater, capite albo, antennis pedibusque nigiis, thorace 

 lineis duabus anticis transversis maculisque quatuor posticis 

 elongatis chalybeis, sciUelli margine postico nitente, abdo- 

 mine lituris duabus basalibus transversis albis maculisque 

 quatuor magnis lateralibus flavis, tibiis piceis, alis limpidis 

 basi nigricantibus. 



Male. — Deep black : head shining, with white shining to- 

 mentum behind and on each side in front ; antennae and legs 

 black ; thorax with a transverse chalybeous line on each side in 

 front and with four elongated chalybeous spots hindward, the 

 outer pair near the base of the fore-wings ; scutellum shining on 

 the hind border ; abdomen with a white shining transverse mark 

 on each side at the base, and with two large yellow spots on each 

 side ; tibiae piceous ; wings limpid, blackish at the base ; veins 

 black. 



Length of the body 4^ lines; of the wings 8| lines. 



Mexico. 



Eristalis expiclus. 

 Mas. — Niger, capite albo, callo, antennis pedibusque nigris, 

 thorace fascia antica interrupta testacea, scutello flavo, ab- 

 domine flavo linea transversa basali vittique angulosa nigris, 

 tibiis tarsisque posterioribus basi genubusque testaceis, alis 

 limpidis basi nigricantibus. 



Male. — Black : head in front white and shining, except the 

 black shining callus ; antennae and legs black ; thorax in front 

 with a testaceous band, which is widely interrupted in the middle 

 and somewhat dilated on each side ; scutellum yellow ; abdomen 

 yellow, with a black transverse line at the base and a black stripe, 

 which is dilated on the hind border of each segment and at the 

 tip ; posterior tibiae and tarsi towards the base and knees tes- 

 taceous ; wings limpid, blackish at the base ; veins black. 



Length of the body 4 lines ; of the wings 8 lines. 



Mexico. 



Eristalis basiger. 

 Fcem. — Fulvus, capite testaceo, thorace vittis tribus anticis 

 duabusque posticis lineisque duabus transversis testaceis, 

 scutelli margine testaceo, abdominis basi testacea maculam 

 transversam fuscam includente, segmentorum marginibus 

 posticis testaceis, alis limpidis vitta antica fusca. 



Female. — Tawny : head with a testaceous shining stripe on each 



