268 NITIDULIDA. 
obtuse and but little rounded. Elytra elongate, truncate at the extremity in the female, 
slightly more rounded in the male. 
We have received a small series of this species showing that the male varies greatly 
as regards the development of the antenne: in some examples they are as long as the 
body, in others only about half as long; in the female they are short, and in this sex 
the first joint of the club is nearly as long as broad, and nearly conical in one of its 
outlines. ‘The species is no doubt closely allied to If. flavicans, Murray, but that insect 
is represented as having a rather slender, long basal joint to the antenne, whereas in 
M. mexicanus this joint is much thickened, and not very long in even the largest males. 
Reitter’s description! was made from a specimen in the Imperial Museum at 
Vienna, and our figure of the male is taken from this individual. Our figure of the 
female is taken from a Panama example; and I am informed by Herr Schlereth, to 
whom I sent specimens of both sexes of the series from Panama, that there is no doubt 
that these examples are of the same species as the Mexican type: this I understand is 
also the opinion of Herr Reitter himself. 
5. Mystrops heterocerus, sp. n. (Tab. VIII. fig. 6, ¢.) 
Brevis, pubescens, obsolete punctatus, ferrugineus, elytris testaceis, circa scutellum fuscescentibus; antennarum 
clava sat lata. 
Long. 14 millim. 
Mas antennis articulis 2°-8™ intus ciliatis. 
Hab. Guatemata, Senahu (Champion). 
Of very short form, with obsolete punctuation, which is quite distant in the male, 
but closer in the female. The antenne are longer and stouter in the male than they 
are in the female, and differ from those of the other species of the genus inasmuch as 
the club is 8-jointed and of normal form; in the male they bear a fringe of long erect 
hairs. Head very short, very obsoletely impressed in front. ‘Thorax transverse, nearly 
straight at the sides; hind angles nearly rectangular, the front angles obtuse and in- 
distinct. Elytra elongate, leaving only the pygidium exposed. Prosternal process 
narrow, elevated along the middle, not bent upwards behind the coxe. Segments 2, 
3, 4 of hind body short, of equal length. Male without supplementary apical segment. 
CYCHROPIESTUS. 
Cychrocephalus, Reitter, Verh. Ver. Briinn, xii. p. 180 (1874). 
Cychropiestus, Reitter, Col. Hefte, xiii. p. 185 (1875). 
In addition to the species of this curious genus found in our region, one other is 
known from Colombia. 
1. Cychropiestus corvinus. (Tab. VIII. fig. 11, 2.) 
Cychrocephalus corvinus, Reitter, Verh. Ver. Briinn, xii. p. 181°. 
Hab. Muxtco ! (Trugui, in coll. Sharp ; Sallé). 
