IO Myron Harmon Swenk 
17. Hair on anterior border of tarsi white; venter with long, dense 
scopal fringes on the apical margins of the segments........... 18 
18. Outer spur of hind tibiae with about a dozen long, coarse 
teeth?® Smaller; ene thes> mins cis. lon aces ctae eee texanus 
18. Outer spur of hind tibiae simple or microscopically ciliate; 
larger; length 9:5: minmasic aeistcl seests antec etetenes serene scopiventer 
19. Abdomen very polished, its first segment subimpunctate; meso- 
thorax smoother with a large, polished disk, scutellum polished 
anteriorly, posteriorly densely, non-striately punctured; 10 
0) 4 ey a Peeters EMR Fis ert a Pi on nea ke Rai fulgidus 
19. Abdomen shiny, its first segment distinctly and closely punctured; 
mesothorax coarsely, shallowly, subcancellately punctured and 
with only a small disk, scutellum coarsely striate punctate, me- 
dially longitudinally depressed and finely substriate............ 20 
20. Vertex and anterior border of thorax with black hair, the 
interocellular tuft largely black; 10-11 mm........... armatus 
20. Vertex and anterior border of thorax with very few or no 
black hairs’ the sinterocellularrttttapaleoenmo. see oneraeee Pal 
21. Pubescence of face, thoracic dorsum, tubercles and base of abdo- 
men pale ochreous, the fasciae tinged with that color; 10 
1371 04 aan ge NT aie ee RAINE” RRS SN SEY ORY LUE yh wt ed 8 angelicus 
21. Pubescence of face whitish, that on thoracic dorsum and tubercles 
tinged with pale ochreous, the fasciae white; 10-11 mm... .tegularis 
(The females of fraserae, hydrophilus and nevadensis are not known.) 
MALES 
1. Middle joints of antennae about as long as wide................. 2 
1. Middle joints of antennae distinctly longer than wide............ 4 
2. Joint 3 exceeding 4 or 5; malar space linear; clypeus con- 
vex, densely punctured and heavily bearded; abdominal 
apices much depressed; 8-9 mm...-.....20.....00% brevicornis 
2. Joint 3=5; malar space one-third to one-half as long as 
wider: cl ypetscleith yy simetente oe eect exces eaten oie RE tore cee 3 
3. Basal joint of hind tarsi about three times as long as broad; 
clypeus opaque, shallowly and weakly punctured; front femora 
not . bearded :+ 9-1 Ovemimiir.. aoser ee ee eee eee willistont 
3. Basal joint of hind tarsi about twice as long as broad and with 
a posterior lobe; clypeus shining, strongly punctured and broadly 
suleate; front femora with a long white beard; 10-11 mm. .latitarsis 
4. Malar space distinctly over one-third as long as wide....... 5 
4. Malar space sublinear, not over one-third as long as wide... 15 
5. Basal abdominal segment distinctly and closely punctured........ 6 
5. Basal abdominal segment sparsely and feebly punctured, or sub- 
Imipunictate 255% kee .clh eis see aetna ete Pee Ie Renta cI ere eee 10 
