250 HYMENOPTERA. 



cence ; the snitellum and post-soutelhun naked, the latter 

 notched in the middle ; the metathorax very densely clothed 

 with long silvery pubescence ; wings hyaline, the nervures fusco- 

 ferruginous, the base of the wings and the costal cell fuscous, 

 the apex of the anterior wings with a fuscous cloud. Abdomen 

 smooth, shining and impunctate. 



Hub. Australia (Port Essington). 



This is possibly the female of S. opulenta ; but, not coming 

 from the same locality, they are separated. 



46. Sphex opulenta. B.M. 



Male. Length 10^ lines. — Black : the face densely clothed 

 with bright golden pubescence, that on the cheeks is less dense 

 and paler ; the mandibles acute at their apex. The pro- and 

 mesothorax above clothed with golden pubescence, the post- 

 scutellura has a similar clothing; the sides of the thorax and the 

 pectus have a thin pale pubescence ; the metathorax very densely 

 clothed with silvery-white pubescence ; the legs have a change- 

 able thin silvery pile ; wings hyaline, smoky at the base, slightly 

 clouded at their apical margins, and having a fuscous spot beyond 

 the marginal cell. Abdomen subopake, with a thin changeable 

 iridescent pile; the petiole covered with silvery-white pubes- 

 cence. 



Hab. Austraha (Richmond River). 



4". Sphex luctuosa. B.M. 



Female. Length 13-15 lines. — Black and shining: the face 

 covered with a thin fine silvery pile and a long stiff black pubes- 

 cence; the cheeks have a silvery pile and a thin long fuscous 

 puljescence ; on the vertex the pubescence is long, thin and cine- 

 reous. The thorax, except the mesothorax above and the scu- 

 tellum, thinly covered with short cinereous pubescence; the 

 metathorax opake, finely rugose ; the mesothorax and scutellum 

 very delicately punctured ; the legs shining black, the tibiae and 

 tarsi strongly sjiinose ; the wings hyaline, dark fuscous at their 

 base and along the outer margin of the externo-raedial cell ; the 

 anterior wings are fuscous at their apical margins beyond the 

 enclosed cells. Abdomen verj' smooth and shining, impunctate, 

 and having a violet iridescence. 



The male only differs in being smaller and in having the legs 

 less spinose. 



Hab. Australia (Swan River). 



This species very closely resembles the Sphex argentata of 

 Dahlbora, but in that species the mesothorax is opake, the 



