191G.] NATURAL SCIENCES OF PHILADELPHIA. 521 
face, a chitinized, median appendage directed caudad and slightly 
ventrad, at the acute apex turned strongly dorsad. 
The CocjnateUa Group. 
Gonomyia (Gonomyia) flavibasis Alexander. 
Gonomyia jlavlbads Alexander; Canadian Entomologist, vol. 48, pp. 317-319 
(1916). 
A western species that is still known only from the type-locality, 
Monterey County, California, July 18, 1896. 
The wing is shown on Plate XXVI, fig. 27. 
The male hypopygium (Plate XXX, figs. 76-78) with the pleurites 
long and slender, the dorsal angle produced caudad as a flattened, 
fleshy lobe that bears many hairs on the dorsal face; first pleural 
appendage very long, flattened, the apex bent, the appendage with 
many long, prominent hairs; second appendage complex, consisting 
of a chitinized hook that is slightly bent; underneath the base of this 
hook is a fleshy lobe with several short bristles on the outer face, 
including two powerful bristles at the apex; above the base of the 
hook is a slender, subchitinized rod that is darkened at the tip. 
Gonomyia (Gonomyia) florens Alexander. 
Gonomyia florens Alexander; Canadian Entomologist, vol. 4S, pp. 316, 317 
(1916). 
A fly of cold Canadian conditions in the northeastern United 
States : 
Maine, Penobscot County, Orono, July 12, 1913 (Alexander). 
New York, Fulton County, Sacandaga Park, June 18, 1916 (Alexan- 
der); Gloversville, June 22, 1916 (Alexander); Herkimer County, 
Indian Castle, June 9 to 13, 1915 (Alexander), the type-locality; 
Tompkins County, McLean, June 5, 1916 (Alexander). 
The wing is shown on Plate XXVI, fig. 28. 
The male hypopygium (Plate XXIX, fig. 71) with the pleurites 
very short and stout, the inner dorsal angle produced caudad into a 
blunt fleshy lobe whose inner margin is fringed with numerous long 
hairs; a short blunt, fleshy knob {k) at the base of this lobe, provided 
with five long hairs on the margin; first pleural appendage {%) slender, 
originating just below the knob {k), directed proximad, the base 
enlarged with two or three stout hairs, the tip slightly bifid, the 
caudal arm with two bristles, the cephalic arm with one bristle; a 
stout bristle just before the tip on the inner or cephaHc side; second 
pleural appendage {2) a powerful, chitinized hook, slightly curved, 
directed proximad, bent strongly cephalad toward the apex; third 
