772 | Assembly 
Similar to the fly last described, in size and in the dots of its 
wings, is another species which Macquart regards as being the 
Tetanocera guttularis, of Wiedemann, although it differs slightly 
from his description. • The genus Tetanocera belongs to a small 
group of the Ortalidan flies, differing from the other genera in 
having the second joint of the antennae equal in length to the 
third joint, instead of being but half as long or less. Another 
character presented by all the species I have seen I do not ob¬ 
serve noticed in books. The whole surface of the wings in our 
American Tetanocerides is finely striated with obtusely impressed 
lines and intervening ridges, which have a longitudinal direction 
towards the apex, and an oblique one towards the inner margin. 
These flies also subsist upon the honey-dew secreted by plant-lice, 
and, according to Desvoidy, their larvae live, some in the unripe 
seeds of plants, others in the parenchyma of the leaves, stems or 
roots. In addition to the guttularis or Dotted-winged Tetanocera, 
we have, common in the State of New York, a species which is 
probably the Canadian Tetanocera (T. Canadensis ) of Macquart, 
although the spots in its wings are sub-hyaline rather than white, 
and there are six only of these spots in the outer or costal cell. 
Associated with this species is frequently found another,, similar 
to it in size and colors, but without any sub-hyaline spots in the 
dusky outer and apical margins of the wings. From that part 
of our State in which I have captured this species, I propose for 
it the name Saratoga Tetanocera ( T'■ Saratogensis ), as the mineral 
waters in this neighborhood have given to the locality a world¬ 
wide celebrity. 
The dried specimen of this fly measures 0.23 to tho tip of the abdomen and 0.80 
to the end of the wings. The head above is golden yellow with two small rusty 
stripes on its fore part, a black spot at base and dot each side anteriorly, almost' in 
contact with the eye, and a second one, also black, on the anterior margin, between 
the eye and the antenna;. Face silvery white. Antenna; light yellow, second joint 
longer than broad, with fine short black bristles along its upper and under edge; 
third joint tinged with brown, narrow and curved, its upper side boing concave, its 
lower side convex and nearly parallel with the upper side, but slightly narrowing 
towards the apex, which is rounded; seta yellowish white, plumose. Thorax palo 
dull yellow, with a faint darker stripe each side of the middle, which stripes have 
an ash gray'reflection when viewed from the front; clothed with a short black 
beard and a few long black bristles. Scutel ash gray with two nearly erect black 
bristles each side. Poisers (the little pedicels back of the insertion of the wings* 
