104 _ Psyche [June 
plate by corresponding thickenings on the dorsal plate. The 
epipharynx is also well marked off from the remainder of the dorsal 
plate because at this point the flexible dorsal plate ends and the 
portion beyond or epipharynx lies above the union of the sete 
and bears ten papillae. These irregular thickenings on the lateral 
walls of the dorsal and ventral plate interlock on either side of the 
canal of the pharynx. Upon a superficial examination these inter- 
locking thickenings appear to be valvular, but closer observation 
shows them to be lateral to the canal and that the canal is closed 
by the dorsal plate of the pharynx being pressed against the ventral 
plate. Situated on the ventral surface of the epipharynx and 
above the diverging setz there is, as stated above, a series of ten 
minute transparent papille arranged in pairs. It has been stated 
by some writers that these papille or glands secrete an oily sub- 
stance which lubricates the sete, which at this point must neces- 
sarily move forward and backward and in close contact with the 
epipharynx and hypopharynx. Others state that these are taste 
organs. The balance of opinion seems to be in favor of the latter 
view, although this point has not been sufficiently investigated. 
Just posterior to the epipharynx on the dorsal plate of the 
pharynx there are four pairs of glands arranged in a line, each 
opening into the pharyngeal cavity. The nature of the secretions 
which these glands empty into the pharynx is not known, but 
probably they are digestive fluids. Above this series of glands is 
attached the first series of pharyngeal muscles. 
Anteriorly and dorsally the pharynx is supported by two struts 
(n), see Pl. 2f. 11and 13, situated lateral to the lateral dorsal portion 
of the pharynx. These struts diverge and extending upward fuse 
with the lateral walls of the clypeus. In addition to these the 
anterior portion of the ventral plate is supported by upward ex- 
tending diverging lateral struts which fuse with the inner walls of 
the fulcra, see Pl. 2 f. 12. At the point where the sete meet, the 
lateral walls of the clypeus pass down on either side of the epi- 
pharynx and setz and meet beneath the setz, thus forming the 
lobes of the clypeus (Ic), see Pl. 2 f. 18. The pharynx is also sup- 
ported by the tentorial structures, but this will be taken up later. 
Below the anterior end of the pharynx lies the salivary pump 
(sp) supported by the tentorium. This very unique pump con- 
sists of a chitinous cylinder and piston. The cylinder is closed at 
