176 Psyche [December 
case resembles the ant in that respect. Besides color the beetle 
is similar to the host in pilosity and, superficially, in form, and in 
life it carries its abdomen erect in a manner similar to the way in 
which the ant holds its gaster. Nothing is known regarding the 
biological relation of the beetle to the ant. 
Dinardella mexicana sp. nov. 
Length 2.75 mm. Head slightly broader than long, rounded at sides and in 
front, posterior border straight; front with a flattened disc. Eyes medium in size, 
flat. Antenne short, extending to apex of elytra; joints in front of the middle 
thickest; first joint as long as the two succeeding together; joints 2-3 longer than 
broad; joints 4-10 transverse; apical joint a little less than twice the length of 
penultimate. Prothorax as long as broad, broadest at posterior fourth, posterior to 
which the sides are straight; anterior and posterior borders straight; disc with a 
faint longitudinal impression. Elytra transverse at base, together considerably 
broader than thorax; sides slightly rounded; the posterior border of each straight. 
Abdomen broad and flat; at base as broad as elytra, the greatest width at the third 
and fourth segments. Legs short and slender. 
Body subshining, finely punctate throughout and covered with a fine mat of 
yellow pubescence; the thorax and elytra bear scattered, erect, black hairs. 
Color dark fuscous to piceous, legs and antenne lighter. 
Described from a small series taken at Pachuca and Guerrero 
Mill with Liometopum apiculatum Mayr. 
Besides being much darker in color D. mexicana differs from D. 
liometopi Wasmann in the shape of the head, which in the latter 
species is distinctly triangular and much broader than long; in 
the thorax not being broader than long, and in having proportion- 
ately longer elytra. 
Zyras (Myrmecia) tapinomatis sp. nov. 
Length 3 mm. Thorax broad; abdomen narrow. Color piceous, except the 
antennz, mandibles, palpi and tarsi, which are fuscous; shining throughout; the 
antenne less so than the body. Head not as wide as prothorax, about as long as 
broad; finely but distinctly punctate. Antenne not extending to apex of elytra, 
thick; first and third joints longer than broad, second joint small; joints 4-10 as 
long as broad, each slightly longer than the preceding; apical joint a little shorter 
than the next two together. Pronotum a little broader than long, with rounded 
sides, the disc at middle very broadly and deeply impressed, the impression about 
one and a half times as long as broad; finely punctate. Elytra together broader 
than long, the sides straight and parallel, punctured similar to pronotum. Ab- 
domen long and slender; about two-thirds as broad as elytra; very shining; the 
third and fourth segments each having on the dorsum a prominent tubercle, the 
anterior of which is the smallest, conical, and bears at the sides a fine mat of re- 
