SUBGENUS TRICHAPION — KISSINGER 333 



group is very closely allied, most of its members exhibit characters 

 common to both groups, i. e., parallel-sided beak in dorsal view in 

 apical half, male tibiae 2 and 3 mucronate, and generally little sexual 

 dimorphism in length of beak. The members of the A. reconditum 

 group are more slender, the elytra are longer in proportion to the 

 prothorax, the basal lateral expansion of the prothorax is more pro- 

 nounced, and the beak tends to be depressed apically. 



The A. oblitum group is similar to the A. patruele group with its 

 robust body and cylindrical beak in apical half, but the base and 

 middle of the prothorax are nearly equal, the beak is abruptly nar- 

 rowed beyond the antennal insertion and cylindrical and polished 

 to the tip, and the male has all three tibiae mucronate. 



The A. nigrum group is similarly stout and has the beak cylindrical 

 in its apical half, but the prothorax is modified so that it is much 

 wider at the middle than at the base, also the front legs of the male 

 are modified either with mucronate tibiae (cordatum), or fore tibia 

 dilated, curved, and set with long ciliae Vv^ithin (heterogeneum), or 

 with dilated or densely pubescent first tarsal segment (nigrum and 

 dolosum). 



The prothorax of the A. rostrum gi'oup is generally about as wide 

 at the base as at the middle. The beak is distinctly attenuate to 

 near the apex, also there is sometimes marked sexual dimorphism in 

 the length of the beak. Some members of this group exhibit further 

 aflBnity with the A. simile section because they have multiserially 

 pubescent elytral intervals. 



Apion {Trichapion) ahdominale Smith 



Figure \2,a,e-g 



Apion ahdominale Smith, Trans. Amer. Ent. Soc, vol. 11, p. 53, 1884. — Fall, 

 Trans. Amer. Ent. Soc, vol. 25, p. 143, pi. 4, fig. 13, 1898. 



Description: Length, 2.25 to 2.40 mm.; width, 1.12 to 1.18 mm. 



Robust. Black; pubescence scant, white, fine, not much more 

 conspicuous on ventral surface. Male beak slightly shorter than 

 head and prothorax combined, one-third longer than prothorax; 

 slightly curved; in lateral view apical half is nearly parallel-sided; in 

 dorsal view strongly expanded laterally at antennal insertion, from 

 middle to apex nearly parallel-sided; coarsely punctured laterally, 

 more finely dorsally, with short, deep sulcus above antennal insertion. 

 Female beak as long as head and prothorax combined, one-half longer 

 than prothorax; moderately, evenly curved, in lateral view sides 

 nearly parallel in apical half; dull, smoother and finely, sparsely punc- 

 tured, tip slightly shining. Antennae inserted at basal fifth of beak 

 at distance from eye equal to width of frons; first segment equals 

 next two, second segment slightly shorter than next two, club 0.24 by 



