Mr. E. E. Turner on Fossorial Ilymenoptera. 437 



Abdominal fasciae narrower 9. 



G. Sixth dorsal segment with a large median 



spot 7. 



Sixth dorsal segment with a spot on each 



side 8. 



7. Sixth dorsal segment broadly rounded 



at the apex B. lobimana, Ilandl. 



Sixth dorsal segment narrowly rounded 



at the apex B. marsupiata, Handl. 



8. Second ventral segment entirely yellow . B, latifasciata, Turn. 

 Second ventral segment black in the 



middle and at the base B. raptor, Sm. 



9. Abdominal fasciae continuous B.Jlaoiventris, Sm. 



Abdominal fasciae narrowly interrupted . B.JIavijjes, Sm. 



10. Tibiae entirely yellow; basal joint of 



fore tarsus with seven spines. Large, 



17 mm. in length B. palmata, Sm. 



Tibise with broad black line ; basal joint 

 of fore tarsus with six spines. Smaller, 

 13 mm. in length B. littoralis, Turn., var. 



11. Third and fourth dorsal segments en- 



tirely black, first with a broad fascia . B. vespiformis, Sm. 

 Third dorsal segment at least with a 

 fascia, when the fourth is entirely 

 black, then the first also without a 

 fascia 12. 



12. Clypeus and labrum entirely black .... 13. 

 Labrum at least yellow 14. 



13. Thorax entirely black B. leeuwinensis, Turn. 



Thorax with lateral yellow spots on 



mesonotum and scutellum B. severa, Sm. 



14. Clypeus entirely black B. atrifrons, Sm. 



Clypeus at least partially yellow 15. 



15. Eyes strongly convergent above, second 



ventral segment with a low carina 



from the base B. cursitans, Handl. 



Eyes not strongly convergent above .... 16. 

 1G. AVith a small yellow spot on each side of 

 the anterior ocellus. Length never 



exceeding 15 mm 17. 



Without a yellow spot on each side of 

 the anterior ocellus. Length always 



exceeding 15 mm B.f areata, Erichs. 



17. Third cubital cell distinctly longer on 



the radius than on the cubitus B. variabilis, Sm. 



Third cubital cell no longer on the radius 



than on the cubitus, if as long B. mackayensis, Turn. 



I have not seen B. lameUata, Hand]., so cannot include 

 the female, in my key. The species of the musca group are 

 so close that I cannot tabulate the females on the insufficient 

 material available. Some of the species of this group appear 

 to have the spines of the fore tarsi much more strongly 

 spatnlate than others ; colour is very variable and not 

 reliable in distinguishing these species. 



