158 Journal New York Entomological Society. [Vol. xx. 



tending all the way across the metasternum and bordered by a row of 

 large punctures ; antecoxal piece triangular in outline, the apex ex- 

 tending between the posterior coxae. 



Anterior and middle coxae globular; the posterior coxae plate-like, 

 extending laterally to the pleurae of the elytra and covering the first 

 3-5 segments of the abdomen ; between the posterior coxae and the 

 abdomen the dumbbell-shaped femora of the hind legs move ; outer 

 anterior ends of the posterior coxae prolonged into knob-like struc- 

 tures, closely fitting into socket-like depressions in the elytra. By 

 this means the elytra are held firmly in place. 



Abdomen with six ventral segments, the first three grown together 

 and covered by the posterior coxae. 



A more detailed discussion of the external morphology may now 

 be given. The head is small, closely fitting into the prothorax which 

 extends a short distance over it. The eyes are prominent, usually 

 strongly convex, not emarginate. The clypeus is well defined, 

 truncate in front. Labrum truncate or emarginate, its anterior edge 

 thickly set with hairs. The mandibles (Fig. 10) are curved, pointed, 

 each with a single tooth on its inner margin. The maxillae consist 

 of the typical parts well differentiated. In Haliplus they are more 

 elongate and narrower than in Peltodyfcs (Figs. 3 and 5) but in 

 general they correspond fairly well. The stipes articulates directly 

 with the cardo and attached along the sides of the stipes are the 

 subgalea (sg, Fig. 5) and the well developed palpifer (pi, Fig. 6). 

 The palpifer bears the 4-segmented palpus and articulates with the 

 dorsal edge of the lacinia (Ic. Figs. 4, 5). On the dorsal side in 

 Peltodyfcs it overlaps the distal end of the stipes and nearly covers 

 the subgalea (Fig. 6). It will be noted that the palpifer is very large. 



The subgalea is attached along its inner edge to the stipes while 

 distally it bears the lacinia. Attached to the subgalea is the large 

 adductor muscle of the maxilla (a, Fig. 4). The 2-segmented galea 

 is attached to the distal outer edge of the subgalea and closely over- 

 lies the lacinia. In the figures the galea is shown somewhat sepa- 

 rated from the lacinia. Sense pits are found scattered over the galea, 

 more abundant towards its distal end. These sense pits are more 

 numerous in Peltodytes (Fig. 5). The lacinia is a large, rather 

 clumsy looking affair. It ends distally in a long, pointed claw and its 

 inner edge is furnished with a row of large, somewhat lanceolate 



