PLACUSA.—HOPLOMICRA. 273 
body is armed in the middle with three elongate rather slender teeth, and on each side 
has a still longer, curved, fine spine. 
Two specimens of this very distinct species have been found. 
10. Placusa crassula, (Tab. VI. fig. 16.) 
Fusca, capite thoraceque omnium densissime vix visibiliter punctulatis, opacis; abdomine nigricante, parce 
punctato, nitidulo; antennis brevibus crassiusculis ; pedibus sordide testaceis. 
Long. 3 millim. 
Hab. GuatEMata, San Gerdénimo (Champion). 
Antenne very short; second and third joints very short, subequal in length; fourth 
and following joints strongly transverse; terminal joint broad and short. Head broad 
and short, but much narrower than the thorax, flat, very dull. Thorax strongly trans- 
verse, almost broader than the elytra, the base slightly sinuate on each side, hind 
-angles indicated by a group of sete, sides much rounded, the surface flat and dull. 
Elytra longer than the thorax, piceous, rather closely and not very finely punctate. 
Hind body rather convex beneath, shining, the base of each segment almost impunctaie, 
a few punctures towards each hind margin. Legs yellow, with the femora more or 
less infuscate. 
The dorsal plate of the seventh segment of the hind body is armed on each side with 
a long, slightly curved spine, and between these teeth is produced and more or less 
rounded. These characters exist in all the sixteen individuals discovered, and probably 
appertain to each sex; but certain individuals, which are probably males, have the 
central lobe more acuminate in the middle, and also an obscure appearance of tubercu- 
lation on the middle of the sixth segment, and a very obscure foveation of the middle 
of the extremity of the central lobe of the seventh. 
HOPLOMICRA. 
Diestote affinis; coxe intermedie sat distantes, mesosternum inter eas sat productum, apice rotundato-acumi- 
nato, cum metasterni processu perparum producto haud conjuncto. 
I am obliged to establish a genus for a minute insect which has a facies intermediate 
between Diestota and Gyrophena, but which cannot be associated with either of those 
genera on account of the incomplete middle acetabula; the raised line marking off the 
metasternal process is only very slightly carried forwards between the coxe, and the 
point of the mesosternum being only of moderate length is thus widely separated from 
it, and there exists a considerable intercoxal isthmus. I have no doubt I am correct in 
seeing only four joints both on the front and middle tarsi; and this character separates 
the insect from Homalota discrepens, which has quite the same facies. 
BIOL. CENTR.-AMER., Coleopt., Vol. I. Pt. 2, September 1883. 2 NN 
