325 
below, where it is separated by one row of setae from the hairless streak 
along the posterior margin, but connecting therewith by means of an arm 
directed toward the base of the wing. Legs rather long, especially the 
middle pair; middle tibiae strongly enlarged at apex; the middle tarsi 
stout at base and tapering toward apex, the first joint nearly as long as 
the four following joints combined; tibial spur stout and as long as the 
first joint of the tarsus. 
Abdomen hardly longer than wide and much shorter than the thorax, its 
apex broadly rounded, the dorsum depressed and slightly concave; ovi- 
positor briefly protruded, the exserted part about one-fifth as long as the 
abdomen, or about equal to the basal joint of the hind tarsi. 
Sculpture throughout extremely fine and alutaceous; under high magnifi- 
zation the surface of the head and notum appears finely reticulate, the 
reticulations of the frontovertex being rather finer than the facets of the 
compound eyes, those of the mesonotum considerably finer still and more 
transverse; frontovertex also with a few larger but very shallow pin- 
punctures not ordinarily perceptible, the mesonotum slightly shiny and 
with minute setiferous punctures; basal tergites of abdomen also with 
extremely fine reticulations. 
Head without conspicuous pubescence, the eyes practically bare, the 
frontovertex with fine short hairs which are not easily seen and arranged 
mostly along the orbits, the occipital margin of the vertex, however, with 
a row of about six coarser black setae; notum of the thorax, including 
scutellum, with rather numerous, seriately arranged, blackish setae; tegulae 
with an oblique row of similar setae. 
General color nearly uniformly yellow, but of different shades due to 
post-mortem changes, varying from light cadmium to cadmium yellow or 
nearly orange (Ridgway), the coloration in life being bright, yellow; the 
lower part of the face, the cheeks, underparts of thorax, and the legs 
somewhat paler yellow; antennae concolorous with the upper part of face, 
the funicle joints often considerably darker or even slightly dusky, the 
club contrastingly very pale yellowish or nearly white; tibiae and tarsi 
slightly more brownish than the base of the legs, the tip of the last joint 
of the tarsi dusky; a spot on the pronotum just above the neck, the 
narrow obliquely placed metanotal selerite on each side of the scutellum 
and the center of the abdomen above more or less extensively behind the 
first tergite are often more or less infuseated, varying from brownish to 
blackish, but any or all of these marks may be faint or absent; a narrow, 
transverse blackish band on propodeum just tangent to the apex of the 
scutellum seems always to be present, but is often interrupted at the 
middle; the vibrissal or cereal plates of abdomen also black, and a minute 
dot beside each of the ocelli usually present, due apparently to pigment 
transfusing from the ocelli after death, as the position of dots in respect 
to the ocelli varies greatly; ovipositor yellow, but usually a little darker 
than the abdomen, the extreme apex often dusky to blackish; mandibles 
