248 MANDIBULATA. HVMEXOPTERA. 



coxis et femorum basi nigri.s, tihiis posticis riifis apice itigro, antennis subtus 

 rufis. (Long. corp. 3 — 44 lin.; Exp. Alar. 5 — 7 lin.) 



Tr. erythrocerus. Gravenhorst, ii. 230. — Steph. Nomen. 2d edit. Gen. 715. 46. 



Black : mouth and face yellow, this last generally with a black dot or longitu- 

 dinal black streak ; anteniise nearly as long as the body, curved at the tip, 

 4 basal joints black, the 1st sometimes with a yellow dot below, the follow- 

 ing beneath red, and the terminal ones totally red ; abdomen somewhat 

 sessile, the basal segment black, with the edge red in the female, the lateral 

 tubercles placed beyond the middle, the 2nd to the 4th red, the latter some- 

 times fuscescent, with the base reddish, the remainder black; legs slender, 

 4 anterior of the male tawny-red, coxae black, sometimes with a yellow dot 

 beneath, trochanters yellow, or black, the base of the femora black; of the 

 female the coxse and trochanters are black, the anterior femora red, with 

 the base black, the middle pair black, with the tip red, tibia and tarsi red ; 

 posterior legs black in both sexes, with the base of the tibiae red; wings 

 nearly hyaline; cellule minute, or wanting. 



Antennae sometimes totally black. 



Taken near London and in Salop, in June. 



Sp, 47. mesoxanthus. Niger, segmento 1-mo tumido, abdominis medio, faciei 

 tibiisque Jlavis, harum posticis apice nigro, (Long. corp. 6 — 6J lin. ; Exp. 

 Alar. 10— 12 lin.) 



Tr. mesoxanthus. Gravenhorst, ii. 233. — Steph. Nomen. 2d edit. Gen. 715. 47. 



Black: palpi pale straw-colour: mandibles in the middle and face orange; 

 antennae porrect, as long as the body, the 1st 20 joints yellow beneath, the 

 colour gradually fading towards the apex ; thorax with a slight griseous 

 pile; metathorax with 2 acute tubercles ; abdomen petiolated, the 3 basal 

 segments of equal width, the remainder gradually narrower, the 1st black, 

 thickly punctured with 2 elevated longitudinal lines, the anterior portion 

 convex and rather swollen, 2nd and 3rd yellow or reddish, remainder black, 

 the 4th with a tawny and semicircular spot at the base ; legs slender, 4 

 anterior with the coxse and trochanters black, the last yellow beneath, 

 femora black, with the apex and entire inner side of the anterior pair yellow, 

 tibiae and tarsi also yellow, the middle pair of the latter fuscous above ; 

 posterior legs black, the tibiae yellow at the base, and the tarsi yellowish 

 beneath ; wings smoky-hyaline ; cellule 3-anguIar, irregular, and somewhat 

 sessile. 

 Rare : taken in the New Forest, about the end of June. 



Sp. 48. nigricollis. Niger, segmentis 1-4 pedibusque Jlavis, horum posticis coxis 

 femoribus et tibiarum apice nigris, ore, macula Jaciali, et antennarum articulis 

 1 et 2 Jlavis. (Long. corp. 4^ — 5 lin. ; Exp. Alar. 7 — 9 lin.) 



Tr. nigricollis. Gravenhorst, ii. 234. — Steph. Nomen. 2d edit. Gen. 715.48. 



Black : face ashy ; mouth, clypeus, and an adjoining facial spot yellow ; tip 

 of the mandibles brown; antennse slender, porrect, the 2 basal joints black. 



