PLATYDEMA. 189 
the regular and distinct punctuation of the thorax, and the somewhat depressed and 
subquadrate form ; the antenne with the three or four basal joints, and the apical one, 
red; the upper surface dull velvety-black, opaque; the epipleure, legs, and under 
surface pale ferruginous; the head similar in both sexes; fresh examples have the 
upper surface evidently pruinose; varying in size from 4-7 millimetres; the sides of 
the thorax are slightly rounded in some examples, in others almost straight. 
I have examined a typical example of P. ventrale and see no reason for separating it 
from P. subguadratum. American entomologists refer this insect to P. janus (Fabr.) 
Lap. & Brullé, on, it seems to me, very questionable authority. An example before 
me, contained in Mr. F. Bates’s collection, named as above by Dr. Horn, is identical 
with our Central-American insect. It seems to me more than probable that P. janus, 
Fabr., from South America, represents another species, and is possibly (to judge from 
the description) the insect here referred to P. sobrinum; P. janus, Lap. & Brullé, is 
from Peru. PP. subguadratum does not, so far as I am aware, extend south of Nica- 
ragua; in the State of Panama it is replaced by P. sobrinwm. Numerous allied 
species with similarly coloured antenne are now known, and in the absence of further 
evidence I prefer not to refer either of our Central-American insects to P. janus. 
10. Platydema sobrinum. 
Platydema sobrinum, Chevr. Petites Nouv. Ent. ii. p. 186 (1877)'. 
?Neomida discolor, Motsch. Bull. Moscou, xlvi. pt. 1, p. 477 (1873). 
?Platydema (Mycetophagus) ganus, Fabr. Syst. Eleuth. 1. p. 566° (nec Horn, Lap. & Brullé). 
Hab. Mexico (Stark), Cordova (Sallé), Jalapa (Hoge); British Honpvuras, R. 
Sarstoon (Blancaneaux), Belize (Blancaneauz, coll. F. Bates); Guatemata, Cahabon, 
Zapote, El Tumbador (Champion); Nicaraeua, Chontales (belt, Janson); Panama, 
Bugaba, Volcan de Chiriqui (Champion).—? Sour AMERIca *. 
A variable and somewhat puzzling species, abundant throughout our region. Rather 
more convex and more ovate than P. subquadratum, the upper surface smoother, the 
thorax not very distinctly punctured, the elytra more finely and shallowly punctate- 
striate. 
In some examples the elytra are much more finely punctate-striate than in others. 
The antenne, as in P. swbqguadratum, usually have the four or five basal joints, and the 
apical one, rufous or ferruginous. 
The two individuals from Belize have the antenne rather shorter, with the penul- 
timate joints more transverse, than examples from the other localities; they can- 
not, however, be satisfactorily separated from P. sobrinum. I have determined this 
species from typical examples (named by Chevrolat himself) contained in Mr. F. Bates’s 
collection. 
It is not improbable that Neomida discolor and N. texana, Motsch., are identical with 
