NEW MALLOPHAGA. 437 



The mandibles (plate lx, figs. 6, 9 and 10) are large 

 and strongly chitinized structures, and evidently perform 

 an important part in the feeding habits of the insect. 

 They are somewhat roughly triangular in profile, having 

 each two points anteriorly and internally, opposing those 

 of the mandible of the opposite side. They lie in a plane 

 parallel to the head. The left one has its anterior surface 

 smooth and a little convex. From the inner edge, a little 

 back of the anterior angle, there projects inwardly and 

 forward a short rounded process. Anterior to this and 

 ventral to it the sharply terminated anterior angle of the 

 mandible forms the second point or tooth. This one is 

 very sharp compared with the other. The ventral surface 

 is concave ventral to the posterior tooth and behind the 

 anterior one. The latter is continuous down the ventral 

 surface as a high wide ridge along the outer side. The 

 posterior part of this surface is also elevated, and at the 

 inner posterior angle is continued inward as a long and 

 somewhat slender projection into the mouth cavity; this 

 tapers distally, but terminates bluntly. At its base are 

 two teeth projecting forward into the concavity on the ven- 

 tral surface of the mandible just described. 



The mandible is articulated to the head by a condyle 

 and a facet. The condyle is on the posterior ventral 

 edge, near, but some distance internal, to the outer pos- 

 terior angle of the mandible. It is a rounded knot pro- 

 iectinp- backward. The facet is situated on the dorsal 

 surface near the same angle of the mandible as the con- 

 dyle. It, however, is not situated on the posterior edge, 

 but somewhat further forward on the dorsal surface ; but 

 it lies in the same anteroposterior dorsoventral plane as 

 the condyle. It faces posteriorly and outward, being sit- 

 uated on an elevation, and the cavity is rather shallow. 

 The right mandible is a little smaller than the left but is 



