This curious insect bears a considerable resemblance to the 

 TenthredinidaB, but is nearest allied to Sirex, as is evident by 

 the triarticulate labial palpi : it may therefore be viewed as the 

 connecting link of Xiphydria and Sirex. The mouth affords 

 some further peculiarities ; and I regret that I did not discover 

 the external part of the labrum, having found only a mem- 

 branous lobe inserted beneath the clypeus : neither could I 

 procure a male for examination. The mandibles are rounded 

 and spoon-shaped, the external lobe of the maxillae is rigid, 

 and the 2nd joint of their palpi the smallest, and the labium 

 is not divided, but hollow and similar to the Ichneumonidae. 



Oryssus is very peculiar in its structure : the sexes vary con- 

 siderably; the antennae, which are inserted under the clypeus, 

 are 11-jointed in the male, and 10-jointed in the female; the 

 oviduct is capillary and rolled up spirally in the abdomen, as 

 it is, I think, in some of the Cynipidae and Diplolepidae ; the 

 submarginal cells are only 2, but 3 are indicated ; the anterior 

 tibiae are so singularly formed towards the apex in the females 

 as to appear like a basal joint to the tarsi, which are only tri- 

 articulate in the fore feet of this sex. 



The only species of the genus is 



O. coronatus Fab. — Curt. Brit. Ent. pi. 460. ? . — Coq. tab. 5. 



I.Set^. 



Black shagreened : eyes fuscous, a white stripe on each side 

 the face ; antennas with the 3rd joint except at the base, the 

 4th, 5th, and a spot at the base of the 6th white ; abdomen 

 smooth and rufous, excepting the 2 basal joints : wings, supe- 

 rior with the apical portion fuscous, excepting the tip which is 

 transparent as well as a band beyond the stigma, this as well 

 as the nervures is piceous; a spot at the apex of the thighs 

 and an abbreviated stripe outside the tibiae white ; tarsi and 

 inside of the posterior tibiae subferruginous. 



Two specimens of this rare insect, taken by Dr. Leach, are 

 in the British Museum : the male is smaller than the female : 

 the former was captured in Devon, the latter in Darent Wood, 

 in July. It is said to inhabit sandy situations : and the disco- 

 very of these insects in England is very remarkable ; for I be- 

 lieve they have never been found to the North of Brives in the 

 South of France. 



Latreille says these insects are lively and restless : they re- 

 pose in preference upon old trees, exposed to the sun. They 

 run over a portion of their height with rapidity in a straight 

 line, taking, when they are alarmed, a lateral or retrograde 

 direction. Scopoli found them upon fir-trees, and Latreille 

 upon old hornbeams in the spring. 



The Plant is Phalaris canariensis (Manured Canary-grass). 



