1925 ] New N emestrinidce from Rhodesia and New Guinea 
17 
Key to the Known Species of Stenobasipteron. 
1. Wings relatively short (7.5 mm.); with a short, but chitin- 
ized axillary vein, bent at an angle in the middle. Proboscis 
shorter than body (4.5 mm.). Ocelli of same size, in an 
equilateral triangle. Front (?) a little narrower than 
one eye. Small species (7 mm.) ( c? unknown) 
S. minimum Bezzi. 
Wings much longer than body, with the axillary vein hardly 
distinguishable, not chitinized, straight. Front of female 
much narrower than one eye. Larger species 2 . 
2. First basal cell with a “bulla” near the base of second longi- 
tudinal vein. ] Ocelli of nearly same size, in an isosceles 
triangle. Style of antenna three-jointed. Proboscis much 
longer than the body (24 mm.). Large species (17 mm.) 
S. wiedemanni Lichtwardt. 
First basal cell without “bulla.” Medium-sized species 
(10.5 to 13 mm.) 3 . 
3. Proboscis much longer than the body (14.5 to 16 mm.). 
Third antennal segment short, slightly over one and one- 
half times as long as wide; style three-jointed, about twice 
the length of the antenna. Length (9): 10.5 to 11 mm. 
(cP unknown). S. arnoldi, sp. nov. 
Proboscis about as long as the body or a little shorter. 
Third antennal segment over twice as long as wide at 
base 4 . 
4. Style two-jointed, about as long as the whole antenna. 
Anterior ocellus (?) occupying a little less than one-third 
of the width of the front. Length ($): 11.5 mm. ( c P 
unknown) 'S. difficile, sp. nov. 
Style three-jointed, much longer than the whole antenna. 
Anterior ocellus ( $ ) occupying a little over one-third of 
the width of the front. Length ( $ , without ovipositor) : 
11.5 mm.; (cT): 11 mm S. gracile Lichtwardt. 
1 This bulla probably corresponds to the minute swellings of the wing 
membrane known as “nygmata” in certain Neuroptera, Trichoptera, Panor- 
pata, and Hymenoptera. They are apparently not known in other Diptera. 
See W. T. M. Forbes, Ent. News, XXXV, 1924, pp. 230-232, PI. V. 
