24 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.64, 



nium. Margin between cardo and occipital foramen convex, sepa 

 rated by a well defined suture from intermediate gular area. 



Gular area, almost fan-shaped, broad in front, attenuate behind: 

 anterior margin convex ; lateral margins concave ; anterior and later- 

 al margins of about same length, and equal to that of the hypostomal 

 margin. 



Optic spot, dorso-lateral, reduced to a blacldsh pigmented point, 

 placed behind the antennal foramen in a distance that is almost equal 

 to the length of the basal antennal joint. 



Antenna, conico-cylindrical, distal end reaching about to the an- 

 terior third of the mandible; basal membrane large; basal joint 

 largest and about as wide as long; second joint half as long and 

 somewhat narrower; apical joint verj^ small and cari-ying a minute 

 seta; supplementary appendix minute; sensorial papillae few and 

 minute ; medium-long setae at the base of basal and second joints. 



Mandible, triangular, with length and width about equal, exterior 

 lateral margin about as long as the hypostomal margin ; axis between 

 the dorsal and ventral mandibular articulations almost perpendicular 

 to the dorsum of the body. Terminal third heavily chitinized, tri- 

 angular, with inner surface somewhat concave ; edge serrate. Median 

 part of mandible thinly chitinized, light colored, wide and with 

 inner margin very convex. Basis and particularly the ventral con- 

 dyle heavily chitinized and dark. 



Maxilla, free, protruding, slightly chitinized, rather slender, three 

 times as long as w^ide (palpus not counted), divided into two almost 

 equal pai-ts; the posterior part probably formed by a fusion of a 

 proximal section of stipes and the cardo ; the anterior part is a distal 

 section of stipes. Mala single, fleshy and rounded, with short setae. 

 Palpus three-jointed, somewhat shorter than the distal section of 

 stipes; rather slender, conico-cylindrical; the joints almost equally 

 long, apical joint about one-third, and second joint about half as 

 wide as the basal joint; short setae on all joints; tactile palpillae on 

 tip of apical joint. 



Submentum, transveree, anteriorly convex with median incision^ 

 posteriorly concave. 



Mentum, transverse, trapezoidal, about twice as wide as long, 

 broadest anteriorly. 



Stipites labii, fused; the joint formation transverse, anteriorly and 

 medianly somewhat incised, as wide as posterior margin of mentum ; 

 no distinct palpiger. Labial palp two-jointed. 



Ligula, absent. 



Paragnathae, not developed. 



Bracon, indistinct but present. 



Tentorium, not observed. 



