SOUTHERN CALIFORNIA ACADEMY OF SCIENCES 105 
Melissodes nigrifrons, Cresson, from California, is a species 
[ have not seen. It may prove to be a Diadasia, as the descrip- 
tion almost exactly agrees with Diadasia nerea, Fowler, difter- 
ing, however, in having the flagellum subtestaceous beneath, 
and the pale hair of the abdomen confined to the first segment. 
Synhalonia idiotes, n. sp. 
Female. Length about 15 mm.; black, head and thorax with 
rather long pubescence, pale ochraceous dorsally, white beneath, 
nowhere mixed with black; head broad, facial quadrangle a 
little broader than long; elypeus entirely black, coarsely 
rugosoe-punctate; antenne dark, flagellum dark reddish beneath 
toward apex; third joint about as long as fourth and fifth to- 
gether; labrum with reddish-orange hairs; mandibles black, 
blunt and simple; blade of maxilla about as long as eye; sixth 
joint of maxillary palpi narrower, but not shorter, than fifth; 
eyes (dry) dark greyish-brown; mesothorax microscopically 
roughened or tessellate, with distinct, well-separated, shallow 
punctures; scutellum more shining, with very close, minute 
punctures, variable in size; base of metathorax minutely rough- 
ened and dull; pleura closely punctured on a minutely rough- 
ened surface; tegule dark reddish; wings somewhat dusky, 
quite hairy, the nervures dark brown; basal nervure meeting 
transverso-medial; first recurrent nervure joining second sub- 
marginal cell at its extreme apex; legs black, with long pale 
pubescence, that on the inner side of the tarsi orange-ferru- 
geinous; scopa of hind legs coarse, little plumose; spurs light 
reddish-brown, simple; knee-plate of hind legs very large, elong- 
ate and pointed, almost half the length of the tibixw; claws with 
divergent denticles; abdomen closely punctured, the hind mar- 
gins of the segments strongly rufescent; first segment with long 
pale hair; segments 2 to 4 covered except apically with a dense 
tomentum, which is white basally (especially towards the 
sides), shading into pale grey. the whole giving the effect of 
narrow reddish and white bands running parallel, and separated 
by broader pale grey bands; fifth and apical segments with 
reddish-brown hair; hair of venta pale reddish, becoming whit- 
ish at sides. 
Hab.—Roek Creek, California (Dr. Davidson, No. 72). A 
pecuhar species, weil distinguished from others by the short, 
broad blade of maxilla, the large elongate posterior knee-plate, 
and the absence of black basal bands on the abdominal seg- 
ments. S. idiotes is the species recorded in Bull. So. Cal. Ac. 
Sei., IV. p. 14, as melissodes sp. from Rock Creek. It was taken 
for a melissodes before the palpi had been examined. 
