hymenoptera. 245 



26. Sphex optima. 



Female. Length 13 lines. — Black : the face and cheeks densely 

 clothed with rich golden pubescence; on the vertex are scattered a 

 few erect fuscous hairs. The prothorax, sides and hinder margin 

 of the mesothorax above, the tubercles and a spot beneath the 

 wings, clothed with bright golden pubescence; the mesothorax has 

 anteriorly a central, abbreviated, impressed line which is coated 

 with golden pubescence ; the post-scutellum has a spot on each 

 side, and the apex of the metathorax is densely clothed with short 

 silvery-white pubescence ; there is also a silvery stripe on the sides 

 at the insertion of the posterior coxa? ; the metathorax is thinly 

 covered with a changeable glittering ]nle, observable in different 

 lights ; a similar pile also covers the legs ; wings yellowish hya- 

 line, their a])ical margins clouded, the nervures black. Abdomen 

 red, with the petiole and three apical segments black ; the third 

 segment has on each side an oblique fuscous line which unites in 

 the middle of the segment ; the fom'th segment has its apical mar- 

 gin narrowly and obscurely ferruginous; the apical segment rugose. 



Hah. Africa (Gambia). 



27. Sphex Bohemanni. B.M. 

 Sphex Bohemanni, Dahlb. Hym. Europ. i. 436. 9. 



Hab. Port Natal. 



28. Sphex pelopceiformis. B.M. 

 Sphex pelopceiformis, Dahlb. Hym. Europ. i. 437- 12. 



Hab. Port Natal. 



The specific characters given by Dahlbom in his tabular synopsis 

 are scarcely sufficient : in the insect for which Dahlbom's name is 

 adopted, the head and thorax have a thin cinereous pubescence, 

 and are closely punctured, particularly the metathorax ; the scape 

 in front, four or five of the basal joints of the flagellum beneath, 

 the clypeus more or less, the mandibles, the coxae and trochanters, 

 the femora and tibiae beneath, ferruginous ; the wings dark fus- 

 cous, with a violet iridescence, the hinder pair pale at their mar- 

 gins towards their base; the petiole elongate; the abdomen ob- 

 long and pointed at the apex. 



The male has no rufous colouring, but otherwise agrees with 

 the female. 



29. Sphex Praslinus. 



Sphex Praslinus, Quer. Voy. Coq. Zool. pt. 2. p. 262. 

 Hab. Port Praslin, New Ireland. 



