THE CANADIAN ENTOMOLOGIST. 187 



green, especially on joint 2. A little later the black shade reappears on 

 the vertex of head, and the dorsal colour of the body becomes dark green. 

 The larvse do not feed in this stage, but enter the ground and form a cell 

 lined imperfectly and with fragile walls. 



Larvse on cultivated rose bushes at Boston, Mass., in June, the flies 

 emerging in July. 

 Neviatus monochroma., Norton. 



6 (? f? ) 4 ? ? • The 9 differs from Norton's description only in 

 having the antennae black, including the two basal joints, and the tarsi 

 dusky. It differs from the descriptions of N. ocreatus, Harrington, and 

 of iV. meHimis, Cresson, in having no black marks on the thorax or 

 abdomen. The metathorax and basal plates are marked with dark brown. 

 The ^ is like the $ below, but above it is largely black. A black patch 

 covers the whole top of the head behind the antennae, except a narrow 

 border to the eyes. Thorax above shining black ; tegulje and posterior 

 angles of prothorax pale. Abdomen black above, except at the extreme 

 tip. In other specimens the black is more extensive, staining the sides 

 below the insertion of the wings and the whole tip of abdomen. 



Larva. — Gregarious, holding to the edge of a leaf by the thoracic feet. 

 Head smooth, shining black, a little paler around the mouth or else 

 entirely pale testaceous, with the eye black ; width, 1.3 mm. Body green, 

 slightly shining, annulate; abdominal feet present on joints 6-1 1 and 13 

 (20 feet), but very small on joint 13. Two transverse rows per segment of 

 elevated black spots, minute on the back, confused laterally and larger, 

 especially two subventral ones. Spots obsolete posteriorly. Colour leaf- 

 green, darker along the back, joint 1 2 tinged with yellowish. Thoracic 

 feet greenish or tinged with black at base. 



Filial stage. — Differs in lacking the black spots. The larvse enter the 

 ground and form neat, dark brown, elliptical cocoons ; that of the ? 

 larger than that of the $ . 



Larviis on poplar at Boston, Mass., in June. The flies emerged the 

 following April. 



Nematus salicis-odoratus, n. sp. 

 (The scented willow saw-fly.) 



I (? , 4 ? ? . $ Length, 5.5 mm. Antennae 4 mm. long, black, third 

 joint a little shorter than fourth. Head pale testaceous, tips of mandi- 

 bles blackish brown ; a large black spot covering ocelli and reaching 

 nearly to base of antennae, continued backward more narrowly to the 



