JAMES A. G. REHN 
361 
material. Of riveti, however, we have before us a series of two 
males and thirteen females, taken at Duran, Ecuador, June 23 
and 28, 1914 (H. S. Parish), and two males and one female from 
Lima, Peru, August 12 and 19 and September 2, 1914 (same col- 
lector), all in the collection of the Academy. The species riveti 
is typical Sympkyloxiphus in palpal proportions, in the general 
contour of the cephalic femora and in tegminal structure, as well 
as in the pattern of lind) coloration. Our material demonstrates 
that macropterism occurs in the genus, all of the Duran material 
having caudate wings, while the Lima specimens have the wings 
atrophied. Correlated with this, as found to be the case in 
Anaxipha, all the macropterous specimens have the cephalic 
tibiae strongly elliptico-perforate on both faces, while those with 
atrophied wings have the foramina on the cephalic face greatly 
reduced or subobsolete. The type material of Chopard, which 
was of the latter type, was described as having the tibiae per- 
forate only on the caudal face. 
The following tentative key to the species which we would refer 
to Sympkyloxiphus, may assist in the recognition and discimina- 
tion of the species. As we have said above, hicolor may not be 
distinct from magnificum, but on this point we cannot make a 
definite statement, as it is the only one of the species here assigned 
of which we have examined no material. 
A. Distal palpal joint hardly, if at all, longer than the third joint, regularly 
tubiform (distal margin transversely truncate). Caudal femora with one or 
more longitudinal lines of black on external face. Cephalic tibiae straight, 
more slender. 
B. Pronotum weakly transverse. Tegmina of female with less regularly 
disposed and more numerous veins in dorsal field. Caudal femora slender. 
Ovipositor slender and more elongate. Cephalic and median femora not 
largely black. abbreviatum (Bruner) 
BB. Pronotum strongly transverse. Tegmina of female with more regu- 
larly disposed and more numerous veins in dorsal field. Caudal femora rela- 
tively robust. Ovipositor robust and shorter. Cephalic and median 
femora largely black. pulex new species 
AA. Distal palpal joint distinctly longer than the third joint, elongate tubi- 
form. Caudal femora without longitudinal black lines on external face. 
Cephalic tibiae as a whole gently arcuate, heavy. 
B. Tegmina ochraceous, more or less marked with brownish, particularly 
on lateral field. Pronotum with the lateral lobes crossed by a broad black 
line. riveti (Chopard) 
TR.\NS. AM. ENT. SOC., XLIII. 
