128 
Psyche 
[December 
are provided with toothed armatures (Plate 11, Fig. 3). 
The setae-like teeth are borne on lightly sclerotized ridges, 
which cross the membrane. There are three such ridges, 
the first of which is incomplete, extending only part way 
down the sides of the pumjp. The second ridge extends 
downward to the midline. These two ridges are completely 
enclosed in the transverse fold, and show only in a sagittal 
section, or when this fold is pulled open for inspection. The 
third ridge is the heaviest of all and occurs on the pos- 
ter oventral edge of the fold where it is visible in the 
ventral or lateral view. This ridge is closely attached by a 
membrane to the heavily sclerotized transverse bar which 
lies immediately behind it. This bar is perhaps the most 
prominent structure in the dorsal wall. It consists of a 
heavily pigmented and sclerotized thickening in the dor- 
sal membrane. It is comma-shaped in sagittal section with 
the tail of the comma extending dorsally and anteriorly. 
The toothed fold is attached by a membrane to this for- 
ward edge. At the posterior edge of the bar is found a 
second, less heavily sclerotized bar which is, in turn, at- 
tached to the one in front by a thin membrane. This second 
bar is provided with a large hollow apodeme on which 
muscle Group 2 inserts. Posterior to this apodeme, the roof 
of the pumjp becomes membranous again, closely resembling 
the structure found in the cibarial portion. It is V-shaped 
in cross section and the muscles attach along the midline 
by means of slender sclerotized apodemes. This region nar- 
rows sharply to form the entrance to the esophagus. 
The floor of the pump is relatively simple. It is heavily 
and uniformly sclerotized along its entire length. As can 
Explanation of Plate 11. 
Figure 1. Ventral view of the food and salivary pumps of Pelocoris. 
Figure 2. Lateral view of the food pump of Notonecta with the lateral 
wall of the floor of the pump cut away. Figure 3. Ventral aspect of the 
roof of the food pump of Pelocoris showing the transverse fold and the 
teeth. Figure 4. Lateral view of the food pump of Pelocoris with the 
lateral wall of the pump cut away. Figure 5. Ventral view of the roof 
of the pump of Pelocoris showing the armature and the lateral fold. 
Figure 6. Dorsal aspect of the roof of the pump of Notonecta. Figure 7. 
Dorsal aspect of the roof of the pump of H esperocorixa. 
