BY ROWLAND E. TURNER. 93 



& 1 *. Head yellow in front; pronotum 



not concave. vernalis 159 



fc 10 . Pronotum ferruginous-red, abdomen 



black. picticollis 165 



6 9 . Pronotum broadly emarginate anteriorly. 



novarce Sauss. 190 

 6 8 . The truncation of the pygidium not ovate, 



widened to the apex. modestus Sm. 199 



b 7 . Fifth ventral segment of the abdomen trans- 

 versely rugose. seductor Sm. 164 



Subgenus i. Phymatothynnus, n.subgen. 



<J. Antennae about as long as the head, thorax and median 

 segment combined, the six or seven apical joints strongly arcuate 

 beneath. Clypeus narrowly produced and truncate at the apex; 

 labrum very small and short, truncate and strongly ciliated ante- 

 riorly, strongly narrowed posteriorly; first joint of the maxillary 

 palpi very short, the three apical joints rather slender, fourth 

 joint the longest; first joint of the labial palpi nearly as long as 

 the three apical joints combined, and the labium has a few long 

 recurved hairs at the apex, Abdominal segments depressed at 

 the base and the hypopygium prominent. 



9. Head only slightly convex. The second abdominal segment 

 has a transverse carina near the base and another at the apex; 

 the intervening space transversely rugose; fifth ventral segment 

 punctured. Pygidium simple, not contracted or truncate. Tarsal 

 ungues bidentate; the basal joint of the anterior tarsi not pro- 

 duced at the apex. 



Type Thynnus monilicornis Sm. 



The mouth-parts of the male closely resemble those of Lopho- 

 cheilus villosus Guer., from which the antennae separate it. The 

 female is quite different and shows some resemblance to Tachy- 

 nomyia. 



1. T. (Phymatothynnus) monilicornis Sm. 



Thynnus (Agriomyia) monilicornis Sm., Cat. Hym. B.M. vii. 

 p.39, n.104, 1859((J9). 



<J. Clypeus short, narrowly produced and truncate anteriorly, 

 with a small tubercle before the apex; the interantennal carina 



