30 GEO. H. HORN, M. D. 



Mandibles are long, slender, acute, moderately curved, directed 

 upwards at an angle of 45° to tlie plane of the head, with a tri- 

 angular tooth slightly behind the middle. There is no trace of the 

 basal molar tooth of the imago. 



Maxill.e — These are semi-corneous, moderately long and consist 

 of a very small triangular basal piece, a moderately long, compressed- 

 cylindric second joint (cardinal piece), which is fimbriate with long 

 hairs on the inner face, a third piece more slender and compressed, 

 somewhat shorter than the preceding with stiff bristles on the inner 

 side, to this is attached a small terminal piece also with bristles. 

 From the thickened base of the third piece arises a thre^ointed 

 jtalpus, the joints of which are gradually shorter, the whole not 

 extending beyond the tip of the maxilla. 



Mkntum. — The mentuin is corneous rather broadly obovate, the 

 posterior edge with slightly elevated margin or bead. The palpi are 

 stout, two jointed and arise from the face of the mentum slightly in 

 front of middle. 



Prothorax. — This segment is slightly broader than the head, of 

 nearly semicircular form, anteriorly broadly emargiuate, the angles 

 nearly rectangular. Along the entire edge (except apical margin), 

 there is a distinctly elevated margin or bead, less evident at the 

 middle of the base. The median line is fine but distinctly impressed, 

 and on each side a sinuous oblicjue impression. 



Mesothorax. — This segment is much narrower than the preceding, 

 trapezoidal, narrower posteriorly, the anterior angles broadly arcuate ; 

 the dorsal surface scarcely at all corneous. At the middle of the 

 anterior margin the scutellum is distinctly indicated. 



Metathorax. — As broad at apex as the base of the preceding- 

 segment, gradually broader posteriorly, sides nearly straight, dorsal 

 surface feebly corneous and with several vaiiue impressions on each 

 side, and a slightly reflexed margin each side of base. j 



Abdomen. — The first four segments are similar in structure. Form 

 transverse, more than twice as wide as long, each gradually longer and 

 wider than the preceding ; on each side of middle a rounded plate 

 of denser structure each with a few short bristles near its posterior 

 margin. The ventral surface of each segment has but one trans- 

 versely oval plate, the short bristles rather irregularly scattered. The 

 fifth abdominal .is broader than any which precede or follow, its dorsal 

 aspect more gibbous, the semi-corneous plates are larger and each has 

 two short corneous spurs of unequal length with dilated base around 



