APPENDIX. 319 



DOLERUS, Jur. 



1. D. inornatiis. Body black, polished ; feet white, tarsi 

 dusk}*. 



Inhabits United States. 



9 Labrum and palpi whitish ; thorax with a line be- 

 fore the wings and wing-scale, white ; scutel with a small 

 bullate white spot on each side; wings a little dusky; ner- 

 vures blackish-fuscous ; pleura with an abbreviated white 

 line over the intermediate feet; coxse colour of the feet. 



Length one-fourth of an inch. 



This species belongs to Dolerus tt of Ze Peletier, Em- 

 PHYTUs, Leach. 



2. D. arvensis. Blackish-violaceous; thorax rufous, a 

 spot before and triangular spot behind, black. 



Inhabits United States. 



9 *^ntenn3eh\a.ck; palpi and mandibles black; head 

 black with a violaceous tinge ; thorax with a longitudinal 

 spot from the collar to the middle, a small spot over 

 the wing, posterior margin connected with a spot, black ; 

 metathorax black ; wings dusky ; pleura and pectus black, 

 tinged with violaceous, the former rufous at the humerus, 

 this colour being connected with that of the thorax ; feet 

 black ; abdomen dark-violaceous. 



Length more than seven-twentieths of an inch. 



Var. «. black spot above the wing enlarged and reaching 

 the dorsal spot. 



This species belongs to Hylotoma, Fabr. Dosythaeus, 

 Leach, and Dolerus, ttt Le Peletier. It is found in the 

 North-west Territory, Pennsylvania, and Arkansa. This 

 species is closely allied to Tenthredo thoracina, Beauv. 

 but it does not fully agree with his figure, and his des- 

 cription is two unessential to be useful. 



