1912] North American Scolune 299 
is more triangular in outline, with the base of the triangle 
below. Except for a small area in the center it is punctured 
everywhere, the punctures gradually becoming deeper and 
closer from the central space outward. It is more or less 
covered with short stiff hairs but the whole surface has a 
shining appearance. 
Frons. The frons extends upward from the base of the 
~ clypeus to the ocelli where it joins the vertex though no suture 
is present. 
There is a downward projection on each side of the clypeus 
to the base of the mandible, narrow in the male and wide in the 
female. A transverse suture extends just behind the ocelli 
and then in some cases a little forward and outward toward the 
eyes. The antenne are inserted in the frons close to its lower 
border, beneath two strongly developed oblique ridges, these 
insertions being slightly farther apart than the distance of 
either from the compound eye. The frons is more or less 
deeply punctured and hairy, particularly so between and 
around the base of the antenne. The hair may become worn 
away to very short stubs, apparently a result of the digging 
habits of the insect. 
Ocell14. The anterior ocellus is the larger. Behind the 
ocelli the head gradually rises to its highest point. It is rather 
sparsely punctured near the ocelli but behind its highest point 
its punctures become quite close again. This portion of the 
head may be termed the vertex but no sutures are present 
separating it either from the cheeks at the sides, the frons in 
front of the ocelli, or the occiput behind. The hinder part of 
the head behind the vertex and cheeks bears a narrow semi- 
circular ridge within which is the articulation with the thorax. 
The back of the head close to the ridge is thickly clothed with 
rather long, stiff hairs. 
Cheek. The portion of the head behind the compound 
eye is called the cheek. Viewed from the side it is widest 
behind the top of the eye. For a short distance downward it 
is of about the same width and then narrows very rapidly to 
- the base of the mandibles. It is punctured and hairy more or 
less everywhere. 
Labrum. A short distance above the lower edge on the 
inside of the clypeus the labrum is attached. In preserved 
specimens it is bent backward at right angles to the clypeus, 
