17 



35.— FRONTINA, Mgn. 



Grn. cIi.— WqmX large, soincwlial; swollen mid vesicular; eyes 

 nude ; frontalia wide and of nearly the same width in both sexes ; 

 faeialia ciliated with strong bristles fully half way up ; antenna) long, 

 1 he second joint sliort, but the third mostly six times longer; arista 

 bare ; abdomen ovoid, with or without discal setje on the middle rings ; 

 wings without cubital appendix, having the fourth vein bent at an 

 angle, and the first posterior cell a little open, terminating near the 

 apex of the wing. 



1 (2) Abdomen yellow \. lata, W Am. 



2 (1) Abdomen black 2. nigricans, Egg. 



F. IjMTa., Wdm. 



T. JcetahUis, Ztt. 



Frontalia of nearly equal wiilt.hs in both sexes, central stripe rufous, of about 

 the same width as the sides, which are of a golden-yellow colour ; face oblique, 

 whitish-yellow ; cheeks bare ; faeialia strongly but not thickly ciliated nearly to the 

 top ; fronto-orbital bristles partly double in both sexes, extending a little below the 

 root of the arista, rather lower in the male than the female ; antennae with the first, 

 second, and basal half of the third joints yellow, the lower part of the third joint 

 (wliich is six or seven times longer than the second) being grey ; arista thickened 

 rather beyond the middle ; palpi yellow ; thorax and scutellum covered with golden- 

 yellow pubescence, the former marked by two narrow central stripes, and having two 

 little, detached, narrow, oblong spots on each side ; the post-sutural outer dorso- 

 central bristles four in number ; abdomen yellow and translucent with white 

 reflections, and having a rather indistinct black dorsal band, more marked and wider 

 in the male than female ; the third segment has the posterior margin black ; both 

 discal and marginal setae are present ; wings yellow, first posterior cell partly open ; [1781 

 legs grey, with upper surfaces of the femora and tarsi black, and tibia- ferrugiuou.s ; ''"'y' 1^-'- 

 the legs are paler in the female than in tlie male. Very rare. 



F. NIGRICANS, Egg. 



Black and glabrous ; frontal stripe piceous, about as wide as the sides of the 

 frontalia, which are rough and vesicular, of a grey colour, with black reflections ; 

 fronto-orbital setae large, and reaching to the end of the second antennal joint ; 

 cheeks white, with dark reflections, and ciliated with a row of small hairs, which 

 extend half way down the face ; facial setae long and strong, extending more than 

 half way up the face ; vibrissae large ; antennae grey, with the third joint thick, and 

 from five to six times longer than the second ; arista thickened to the middle ; palpi 

 black ; thorax black and shining, the front margin, with the shoulders and sides 

 being clothed with white pubescence, it is marked by four longitudinal black stripes, 

 the middle pair being narrow, and the outer ones wide ; there are four post-sutural 

 outer dorso-central bristles; scutellum black, with the apex sometimes rufous; 



