3 02 
The Ohio Naturalist. 
[Vol. Ill, No. 1 , 
two prominent curved spines on its anterior end. On the tip of 
the stipes and between the palp and the lacinia is the galea (7') 
covered with bristles and ending in an incurved spine. It is some- 
what shorter than the palp and longer than the lacinia. The labium 
(8'-9’) lies on the median ventral surface and is attached pos- 
teriorly to the anterior margin of the submentum, and lies between 
the lateral projections of the submentum and under the labrum. 
The parts which are separate in other beetles seem to be fused in 
this. The labium seems to be composed of mentum (8’) ligula 
(9’) and paraglossa fused. The palp is as in other forms. The 
proximal portion (8’) probably corresponds to the mentum, the 
median anterior spine to the ligula (9’) and the rounded lateral 
elevations lying on either side of the spine to the paraglossa ; the 
pahp is three-jointed. 
THE PRO-THORAX. 
The following definitions should be kept in mind : A typical 
body segment of an insect is composed of four main pieces or 
sclcrites. The dorsal portion is called the tergum. The side pieces 
are called pleura and bear spiracles when present. The pleuron is 
divided into two smaller sclerites, the anterior or episternum and 
posterior or epimeron : owing to the flattening of the body dorso- 
ventrally in beetles the sclerites of the pleura lie on the ventral 
surface. The ventral portion of the segment is called the sternum 
and is usually modified according to the size and method of articu- 
lation of the limb. The dorsal portion or tergum is also similarly 
modified by the attachment of the wing. 
The pro-notum (4-7) or pro-thoracic tergum. is a smooth 
rectangular sclerite covering the dorsal surface of the pro-thorax. 
It is divided into right and left halves by a longitudinal suture. 
Anteriorly it ends in a sharp border, but laterally and posteriorly 
it is inflexed to unite with the sclerite forming the ventral wall of 
the body. 
The prosternum (1) occupies the median ventral portion of 
the pro-thorax. It is compressed in the middle region between the 
pro-thoracic coxae and expands posteriorly into a small diamond- 
shaped piece. Anteriorly it expands almost to the lateral border 
of the coxal cavities. The suture limiting the lateral area of the 
anterior end of the pro-sternum is V-shaped, the apex of the V 
pointing toward the median line. The transverse depression on 
the median anterior portion is not a suture but is the remnant of 
the fold where the articular portion of the pro-sternum was 
doubled under in the pupa. 
The pleuron is usually composed of two sclerites. the anter- 
iorly located episternum, the posteriorly located epimeron, and 
sometimes a third dorsally located epipleuron. In Passalus they 
