38 Psyche [March- June 
right angle; posterior corners of the first and second posterior 
cells with well developed spurs. 
Holotype: No. 23794, one female. Bartica, British Guiana, 
August 19, 1901, collection C. W. Johnson. 
This fly, which is a true Mixogaster because of the fact that it 
lacks any spur or vein from the third longitudinal vein into the 
first posterior cell as well as by its petiolate form, is characterized 
by its light brownish yellow color and large wings. It was com- 
pared at the British Museum by myself with the type of anther - 
mus Walk, and found to be very close to that species differing, 
however, in particulars of the wing venation. It is also close to 
anthermus from the Amazon region in other respects, differing 
in the less developed occiput, the less retreating face and in 
the presence of the lateral yellow spot anterior to the suture of 
the thorax, in the absence of a much reduced brown square upon 
the metanotum and in the isolated brown spot around the ocellus. 
There are probably other differences but the general pattern 
coloration in the dried specimens leaves the markings obscure. 
Planes proxima n. sp. 
Related to vagans Wied., the anterior tibiae are extensively dark 
brown, the lower part of the face is reddish brown and the ab- 
dominal pattern is different. 
Female. Length 9.15 mm.; wing 6.8 mm. Head: eyes bare, 
vertex in front shining bluish-black, the latter with a broad sil- 
very pubescent band from eye to eye which is indented above 
and below in the midline; almost the whole of the face is covered 
with pale greyish-white pubescence, worn off a little on either side 
below the sharp facial carina; ground color of the face metallic 
black, except that it is obscurely reddish on either side above the 
oral margin; the face is retreating and in profile very shallowly 
concave on the lower part. Antennae elongate, the first and 
second joints dark brown, the third reddish basally and on the 
ventral third but otherwise dark greyish-brown; arista long, 
slender, reddish. Thorax: obscurely shining black, chiefly short 
pale pilose, with some black pile along the middle behind the 
suture and more extensive black on the sides behind the suture 
but beginning to vanish as it reaches the posterior calli. The pile, 
then before the scutellum is broadly pale, somewhat appressed 
and more or less directed forward and towards the sides. Seen 
from behind there are a pair of widely separated, broad, median 
