22 Trans. Acad. Sci. of St. Louis. 



modification of this fold in the present subtribe is accom- 

 panied by so many peculiarities of habitus or specialized 

 structure as to indicate its really important nature from a 

 generic standpoint, and I have therefore used it as one of the 

 primary criteria both here and in the Lathrobia, where it 

 apparently loses none of its significance. In the Cryptobia 

 the fold is present as a rule and its absence is the exception, 

 while the reverse is the case in the Lathrobia, there being 

 more species in the latter without than with this plication. 

 The anteriorly flexile antennae, with greatly elongate basal 

 joint, and the undilated anterior tarsi, are the only important 

 characters distinguishing the Cryptobia from the Lathrobia, 

 the large conical glabrous fourth palpal joint being common 

 to the two, but in the table of subtribal groups it is necessary 

 for convenience to separate them by a few subtribes having 

 the fourth joint completely different in form, being com- 

 pressed and finely pubescent. This difficulty of course arises 

 from the practical necessities of a lineal succession in the 

 grouping. The genera represented by material in my cabinet 

 may be defined as follows : — 



Gular sutures separated; maxillary palpi coarsely and very sparsely setu- 

 lose; pleural fold when present never united with the side margin 

 posteriorly 2 



Gular sutures united throughout tbeir length from the small triangular post- 

 mental piece; third palpal joint finely and closely pubtscent; pleural 

 fold gradually becomiug fused with and forming part of the side margin 

 poster i orly 12 



2 — Elytra with a pleural fold near the side margin 3 



Elytra without trace of a pleural fold 7 



3 — Pleural fold entire, extending from the humeri to the outtr angle of the 



elytra 4 



Pleural fold incomplete 6 



4 — Neck entirely unconstricted on the upper and lower surface, feebly 



constricted at the sides, very broad and but slightly narrower than the 

 widest part of head, the latter elongate and rather depressed, but 

 little narrowed before the eyes which are moderate in size and ant rior 

 in position; two post- ocular setigerous punctures — characterizing 

 most of th? genera — wholly obsolete; labrum short, edentate, feebly 

 and biobliquely truncate, with a small median sinus ; lobes of the ligula 

 large, obtriaugular, apparently connate throughout their length, mem- 

 branous, the basal part corneous; mentum large, trapezoidal, with more 

 than apical half coriaceous, uuimpres-ed at base; gular sutures more 

 widely separated than usual, straight and only very slightly converging 



