19 16. J NATURAL SCIENCES OF PHILADELPHIA. 537 
to North Carolina. It is a species of low swampy areas, though 
usually more wooded than that frequented by inconstans. In New 
York and New England it Hies from May 22 to October 1, being 
abundant in late May and early June, reappearing the latter half of 
July and being common throughout August and early September. 
The late summer specimens probably represent a new species, the 
females having the wings very reduced in size. 
Tricyphona auripennis Osten Sacken. (Plate XXVIII, fig. 49.) 
Canadian life-zone of the northeastern United States, kno"svn only 
from New Hampshire, Massachusetts (the type-locality) and New 
York. It flics in June. The only specimens ever seen alive by the 
author occurred at Indian Castle, Herkimer County, New York, 
June 10 to 13, 1915; they were found sitting motionless on the 
perpendicular face of a small cliff, lurking in small crevices of the 
rock. The cliff is low, of Utica shale, completely saturated by 
percolating water and well-shaded by large hemlocks, arbor vitse, 
yellow birch, mountain maple, Cornus circinata, etc., and mth a 
sparse vegetation of Impatiens hiflora, Geranium Robertianum, 
Collinsonia canadensis, Cystopteris hidbifera and Equisetum arvense. 
Tricyphona hyperborea Osten Sacken. (Plate XXVIII, fig. 50.) 
A fly of the Hudsonian and possibly the Canadian life-zones of 
northeastern America and still very rare in collections. It was 
described from Labrador, and a few specimens have been taken on 
Mt. Washington, New Hampshire; these specimens are in the col- 
lections of the Boston Society of Natural History and the United 
States National Museum. 
Tricyphona katahdin Alexander. (Plate XXVIII, fig. 51.) 
Canadian life-zone of the northeastern United States, a late 
summer species flying during the latter half of August. 
Tricyphona vernalis Osten Sacker. (Plate XXVIII, fig. 52.) 
Canadian and Canadian-Transitional zones of the northeastern 
United States. One of our early-flying species, though appearing 
later, as a rule, than paludicola. It ranges from Maine and New 
Hampshire south (in the mountains) to Georgia, and is found along 
small streams, temporary and permanent, where the water runs 
rapidly. The flies may be swept from vegetation or are found in 
small swarms of eight to ten individuals near the water. In New 
York and New England it is on the wing in late May, abundant in 
June and persisting into July. Further south it flies in April or 
even the last of March, reappearing in late September. 
