BORBORUS. 175 



the base below with a hook, the small second spur of the hind tibiae is 

 twisted and angular, and catches on the hook. Fore metatarsus slightly 

 unguiculate at the tip ; first and second joints of hind tarsi covered 

 below with yellow down, the latter thickened. Fern. Fore femora only 

 thickened ; hind femora with a tubercle instead of the hook ; basal 

 joints of the hind tarsi more slender than in the male. 

 Not common. (E. S. I.) 



2. suillorum, Hal. E. M. in* 322. 2 (1836). tibialis, Desv. 

 communis, Desv. punctipennis ? Mcq. Niger, nitidus, alls ferrugineis, 

 venis transversis infuscatis, halteribus albidis. Long. 1 ; alar. 3 lin. 



Very like B. nitidus, but the transverse veins of the wings are con- 

 stantly suffused with brown ; the bristles on the outside of the middle 

 tibiae are much finer ; the legs more slender, the femora of the male 

 unarmed, and only the fore pair thickened; the second joint of the 

 hind tarsi is slender ; the posterior coxae, the trochanters and tarsi, and 

 the extreme base of the tibiae, are rust-brown, the fore and hind tarsi 

 darker. Var. Tibiae and tarsi ferruginous ; end of the fore tibiae and 

 base of the fore and hind tarsi brown. 



Not common. (E. I.) 



3. niger, Meig. Zw. vi. 201. 6 (1830) ; Mcq. ; Hal. ; Zett. Niger, 

 opacus, villosus, alis hyalinis, halteribus fuscis. Long. 2i; alar. 4^ lin. 



Dull-black, hairy. Front with a glossy line. Arista thickly pubes- 

 cent. Thorax slightly tinged with green. Wings obscurely hyaline; 

 veins brown. Halteres dusky. Segments of the abdomen nearly equal ; 

 knees and tarsi dusky; fore femora thick, hairy; middle tibiae with 

 strong bristles or spines on the outside ; second joint of the hind tarsi 

 scarcely thickened. Male. Fore metatarsus unguiculate at the tip. 



Not common. (E. I.) 



4. equinus, Fal. Het. 6. 2 (1820); Meig.; Mcq.; Hal.; Zett.- 

 communis, Desv.fuliginosa, Desv. coprivora ? Desv. Arista subnuda, 

 abdominis segmento secundo maximo, tar sis posticis brevibus ; Mas, meta- 

 tarso antico inermi. Long. l-2 ; alar. 3-5 lin. 



Arista with very thin and short pubescence. Second segment of the 

 abdomen much larger than the third. Hind tarsi short, broad. The 

 characters of this species and of its larva are fully described by Mr. 

 Haliday (Ent. Mag. iii. 323, 335). 



Everywhere abundant. (E. S. I.) 



5. nigrif emoratus ? Mcq. D. ii. 567. 5 (1835); Hal. Niger, 

 nitidus, fronte pedibusque testaceis, arista subnuda, abdominis segmentis 

 sub<zqualibus,femoribus anticis, in mare omnibus nigris, maris metatarso 

 antico inermi. Long. 2 ; alar. 4 lin. B. equinus var. ? 



Narrow margin of the front testaceous. Transverse veins of the wings 

 more remote than in B. equinus ; praebrachial transverse vein not reach- 

 ing to one-third of the discal areolet ; second and third segments of the 



