484 MK. K. E. TURNER ON [May 12 



tarsi, the apex of the femora, and the apical margin _ of the fifth 

 abdominal segment veiy narrowly ferruginous. Wings hyaline, 

 nervures ferruginous. 



J . As in the female, but the pubescence on the head and 

 thorax is longer and duller, the anterior margin of the clypeus is 

 more rounded, the apical margin of the abdominal segments is 

 broadly dull ferruginous with the band of pubescence as in the 

 female on the four basal segments, the pubescence on the apical 

 segment is whitish, and the posterior femora are black at the base 

 only. The abdomen is more closely punctured than in the female. 

 The eyes are yellowish green in both sexes in life. 



Length, $ 14 mm., c? 13 mm. 



Rab. Mackay, Queensland {Turner) ; February and March, 



Key to the Australian Species of Tachysphex. 



A. Abdomen wlioll3r black. 



a. Tibiae and tarsi light ferruginous T. imhelUs. 



h. Tibife and tarsi almost entirely black 

 a-. Abdomen opaque, covered "vrith very short pubescence. 

 c(?. Mesonotum not visibly punctured ; abdomen sub- 

 opaque T. fortior. 



Ifi. Mesonotum very distinctlj' punctured ; abdomen 



opaque T, mackay ensis. 



h". Abdomen more or less shining, pubescent on the 

 apical margin of the segments only. 

 d^. Dorsal surface of the median segment longitudinally 



striated T. walker i. 



Ifi. Dorsal surface of the median segment not striated, 

 a"'. Thorax and median segment strongly pubescent . T. pilosulus. 

 h*. Thorax and median segment not pubescent. 

 «-5. Median segment longer than the mesonotum... T. tenuis. 

 ¥'. Median segment not longer than the meso- 

 notum. 



a^. Mesonotum subopaque T. deli His. 



b''. Mesonotum shining. 



a'. Pronotum sharply sloped. 



a^. Second joint of the fiagellum much 



longer than the third. Length 8 mm. . T. ijacijicus. 

 Ifi. Second joint of liagellum shorter than 



the third. Length 13 mm. T. nigerrimiis Sm. 



6'. Pronotum graduall.y sloped. 



a^. Head shining, almost smooth. Wings 



and antennas short T. pucjnator. 



h^. Head opaque, finely punctured. Wings 



and antennae of moderate length T. liypoleius Sm. 



B. Two basal segments of abdomen ferruginous red T. trtmcatifrons. 



Tachysphex truncatifroxs, sp. n. 



2 . Mandibles very strongly incised on the outer margin. 

 Clypeus broadly truncate on the apical margin, slightly convex in 

 the middle, obliquely and broadly triangularly truncate from the 

 middle to the apex, the base opaque and indistinctly punctured, 

 the surface of the truncation shining, with a few scattered 

 punctures. Antennfe inserted as far from each other as from the 

 eyes ; the second, third, and fourth joints of the fiagellum abou^^ 

 equal in length, each at least three times as long as the first joint 



