E. ternaria (group). Two specimens so named were captured at Three Forks Aug. 19, 1925 and Sept. 4, 1926.

1310 E. atropulverea Sm. One specimen in Smith collection taken at Butte, Aug. 28. 1900, by R. A. Cooley. One specimen from Bozeman, Aug. 27, 1929. 1310. I E. setonia McD. One specimen taken at Three Forks July 22, 1926 by C. B. Philip.

Length 7 mm.; width at the humerus 3.2 mm. Elongate, with the sides of the elytra almost parallel. Black with a slightly aeneous lustre; the lateral bead of the pronotum, the sides of the elytra and the two spots on the head, reddish; the labrum is cream; the antennae are pale with the apices of the segments beginning with the sixth, infuscate; the palpi are pale with very slightly infuscate apices; the legs and coxae are pale red with the femora darker. The under surface is black except for the posterior borders of the abdominal segments which are narrowly reddish. The pronotum is notably unicolorous except for the marginal bead.

The literature contains but few definite records of Corixidae from Eastern Canada although many species have been described from adjacent territories and without doubt are present in the Canadian fauna. Recent collecting at various points in Ontario and Quebec has resulted in procuring new records for several species of Arctocorixa. The following constitutes a preliminary list of the Arctocorixa species of this region.

The Dolichopod herewith described belongs to a genus containing a large number of species having very similar form. The new form is related to tristis Loew but is readily distinguished by the wholly black legs.