3°4 
The Ohio Naturalist. 
[Vol. Ill, No. 1 , 
borne between the claws, and also a prolongation of the last seg- 
ment called the pulvillus. The tibial joint opens forward in the 
first pair of legs and backward in the second and third pairs. The 
trochanter lies on the anterior surface of the first pair, but on the 
posterior surface of the last two pairs. By comparing this leg 
with the last two it will be seen to be rotated forward, that is, 
structures on the posterior surface of the first leg are on the an- 
terior surface of the last two pairs. 
The trochantin is situated on the outer end of the coxa. It 
is convex and presents three faces, an outer or lateral, which is 
smooth ; an inner or dorsal, which furnishes attachment for the 
dorsal muscles, and a ventral face, which furnishes attachment 
for the ventral muscles. It is articulated by its posterior border 
with the coxa and lies in a depression of the anterior arm of the 
coxa below and in front of the point of articulation of the coxa 
with the body wall. 
The jugular sclerites (13) are small pieces lying between the 
posterior ventral portions of the head and the anterior portion of 
the pro-thorax. The anterior surface is concave and smooth. It 
articulates with the head and is attached to it on its ventral inner 
border by a strong ligament. The ventral portion of the posterior 
surface is smooth and protrudes from under the pro-thoracic ster- 
num. The dorsal two-thirds of the posterior surface is rough 
and bears a posteriorly directed process which gives off a ventral 
keel and a lateral one which runs to near the inner border. 
The meso-thoracic spiracle lies on the hinder border of the 
coxa in the membrane connecting the coxa to the posterior border 
of the pro-sternum and epimeron. It is not visible from the ex- 
terior but can be seen by removing the coxa. It is very large, 
being about four millimeters in length. 
THE MESO THORAX. 
This segment articulates anteriorly with the pro-thorax and 
is fused posteriorlv with the meta-thorax. It is much narrower 
than either of these segments and bears on its dorsal surface a 
strongly chitinized elytra or- wing cover, and on its ventral sur- 
face the second pair of walking legs. The meso-thoracic tergum 
of some beetles contains four sclerites, the prescutum, scutum, 
scutellum, and postscutellum. The prescutum and postscutellum 
are frequently wanting. 
The scutellum (6) lies on the mid-dorsal line of the meso- 
thorax. It is triangular with the base of the triangle directed 
forward. It is free in front, and laterally is continued under the 
triangular base of the elytra in a less chitinized area which finally 
is continuous with the articular membrane of the elytron. Pos- 
teriorly it is fused with the postscutellum. The postscutellum (7) 
