DESCRIPTION OF NEW SPECIES 143 



disk moderately convex basally, arcuately declivous antero-laterally. 

 densely but not coarsely indentato-punctate. 



Elytra oblong-oval, about twice as long as wide, humeri rather 

 prominent ; disk not strongly punctate, punctures shallow, separated by a 

 distance equal to two or three times their diameters, surface micro- 

 scopically reticulate; apex parabolically rounded, sutural angles rather 

 more than narrowly rounded. 



Abdomen finely and sparsely punctate, surface microscopically reticu- 

 late. 



Legs rather short. 



Male. Slightly narrower. Fifth ventral segment arcuato-truncate 

 at apex. Antennal joints five, six and seven similar in form, subtriangu- 

 lar, more prominent anteriorly than posteriorly, eighth smaller by one- 

 eighth. 



Female. Slightly broader. Fifth ventral rather parabolically 

 rounded. Antennae slightly more slender, joints six and eight smaller, 

 similar in form ; tenth and eleventh feebly transverse, sides arcuate and 

 symmetrical. 



Measurements. Length (Types), 2.9-3 mm.; width, 1-1.2 mm. 

 Holotype, male, and allotype, female, and two paratypes in my own 

 collection. 



Type locality. Colorado, without definite locality. 



In senilis the pubescence is coarse, dense and cinereous, and the tenth 

 antennal joint is transverse ; in davicornis the pubescence is moderately 

 long, not so coarse, and the tenth antennal joint is transverse as in senilis, 

 while in coloradensis the pubescence is coarse on the head, pronotum and 

 elytral base, the antennae are almost similar in the sexes, and the fifth 

 ventral abdominal segment is arcuato-truncate in the male. Col. Casey 

 has examined specimens of this species and pronounced it new. 



Listrus dilutus, new species. Sexes similar in form, oblong-oval, 

 subparallel and somewhat robust, moderately convex. Color black, with 

 a dark virido-metallic lustre ; tarsi rufous to rufo-piceous. 



Pubescence very short and inconspicuous, rather plumbeo-cinereous 

 in color, recumbent and moderate in abundance. The maculation is 

 difficult of determination, dark areas invested with dark-brownish hairs. 

 Basal fascia is represented by a large parascutellar and a humeral macula 

 on each elytron ; a variable post-basal macula at middle of each which is 

 frequently connected to the humeral forming a lunule; median fascia 

 rather broad, edges feebly zig-zag, usually more or less interrupted at 

 suture ; subapical fascia rather wide, more or less entire and tending to 

 dilate on the suture, edges rather irregular ; apical maculae variable as to 



