•232 REVISION OF THE THYNNID.E OF AUSTRALIA, I., 



R. TRISTIS Sill. 



Rhagigdster tristis Sm., Cat.Hym. B.M. vii. p.63,ii.l3, 1859(^). 

 • Thynnus hammerlei D.T., Cat. Hyiii. viii. 108, 1897(^). 



The clypeushas a very short carina from the base, then branch- 

 ing, the space between the ])ranches smooth and shining. A 

 very faint V-sliaped carina between the antennae. Head, thorax 

 and median segment punctured-rugose, most coarsely on the 

 mesothorax and scutellum; the nrothorax with the anterior angles 

 slightly prominent; the scutellum narrowly truncate at the apex. 

 Abdomen slender, rugulose, segments 2-5 with a depressed trans- 

 verse line at the ])ase and a smooth, polished, raised mark on 

 each side near the apical margin. Epipygium coarsely punctured 

 at the base, smooth and rounded at the extreme apex. Black; 

 wings h3^aline, iridescent, nervures black. Length 11 mm. 



9. Unknown. 



Hah. — Western Australia. 



R. DENTICULATUS, n.sp. 



^. Cl3'peus densely clothed with grey pubescence, with a 

 median carina from the base to the apex. Head rugulose. finely 

 punctured on the occiput. Prothorax rugose, moderately pro- 

 duced at the anterior angles; mesothorax and scutellum coarsely 

 rugose. Median segment very densely punctured, obliquely 

 depressed to the apex. Abdominal segments punctured, with a 

 depressed transverse line near the base and a raised mark on each 

 side near the apical margin of segments 2-5. Epipygium rugose, 

 with a spine on each side near the l)ase, the apex narrowly 

 truncate. Entirely black, legs fuscous. Wings fusco-hy aline, 

 slightly iridescent. Length 11 mm. 



9. Head much longer than broad, rectangular, shining, sparsely 

 punctured. Prothorax very faintly punctured, with a depression 

 on each side, broad and deep on the posterior margin, reaching 

 nearly half-way to the anterior margin, but becoming narrower 

 and less deep. Median segment more strongly punctured, with 

 a faint median longitudinal carina, oblic^uely truncate at the apex, 



