OF SUCTION IN LYGUS PABULINUS., ul 
(A) The Mandibular Levers. (Text-fig. 19, Md.L.) 
These are attached proximally to the lateral wall, or maxillary 
sclerite, just below the bases of the antenne, and distally to the 
mandibles through a igament. Their distal connection enables 
the levers to pull down the mandibles when the protractor muscles, 
Text-figure 21. 
0.M._ 
Mx. St... 
with 
Mx.L. 
Lygus pabulinus. 
Transverse section, showing the maxillary levers, ete. Ob. 3 & Oc. 8. 
For explanation of the lettering see p. 693. 
which are attached to the former, contract. Proximally, at the 
bases of the levers, there is no hinge-like device but, on the 
contrary, they are fused with the sclerite. They are bifurcated 
distally, the mandibles passing through the fork. 
Their functions are :— 
(i.) They give attachment to the protractor muscles of the man- 
dibles, which muscles are attached to the distal ends only. 
(u.) The maxillo-mandibular muscles are attached to them. 
(Text-figs. 20, 21, Mx.Md.M.) 
(ui.) The antagonistic muscles, which serve to bring back the 
levers to their normal positions, are also attached to them. 
(Text-figs. 5, 20, A.M.) 
(iv.) The mandibles are supported by them. 
(B) The Maxillary Levers. (Text-figs. 1,5, 21, Mx.L.) 
These are narrow and elongate, and have no connection with 
the lateral walls of the head. Their proximal attachment is to 
the posterior arms of the tentorium, and distally they are con- 
nected with the maxille. They taper gradually towards their 
