HEMIOSUS.—LIMNOCHARIS. 85 
plate raised along the middle, forming a broad, flattened carina ; the following segments 
with a short and therefore very inconspicuous elevation at the base in the middle; 
apical segment notched after the manner of Berosus. Legs of moderate length ; inter- 
mediate and posterior tibiz and tarsi rather feebly ciliate; all the tarsi 5-jointed, but 
the basal joint excessively short. 
1. Hemiosus maculatus. (Tab. III. fig. 2.) 
Oblongo-ovalis, convexus, capite thoraceque densius fortiter punctatis, metallescentibus, hoc utrinque versus 
basin foveola rotundata ; elytris striatis, striis e seriebus regularibus punctorum majorum compositis, 
interstitiis fere impunctatis, testaceis plus minusve metallescentibus, maculisque magnis fusco-nigris: 
subtus nigricans, maxime opacus; pedibus testaceis, femoribus sericeo-opacis, fuscis, antennarum basi 
palpisque testaceis, his apice summo fusco. 
Long. 14, lat. 2 lin. 
Hab. GuaTEMaLA, Pantaleon, 1700 feet (Champion). 
Head broad, densely and coarsely punctate. ‘Thorax strongly transverse, but narrower 
than the elytra; the sides nearly straight, scarcely narrowed behind ; the surface entirely 
metallic, very densely and coarsely punctured, with a small round deep fovea close to 
the base on each side. Elytra with very regular series of very large and deep round 
punctures, placed very near one another, but each puncture separated from the rest by 
a distinct though very short transverse interstice: these series are ten in number ; 
there is also another series concealed by being placed extremely close to the somewhat 
inflexed lateral margin, and also a short basal series between the first and second 
series: the colour is an obscure yellow, with large dark spots; but the surface 
has a rather strong metallic reflection, especially along the suture and about the dark 
spots and large punctures. The legs are of moderate length; the extremely fine 
dense pubescence on the femora renders them very dull; and the opaque portion is 
separated by an extremely abrupt line of division from the very polished, small, apical 
portion. The very fine pubescence of the under surface appears cinereous, or even 
almost white, in certain lights. 
The colour and sculpture of the upper surface of this little insect remind one rather 
of Helophorus than of Berosus. I see no external sexual distinctions in the series of 
fourteen individuals sent by Mr. Champion; the apical ventral notch has a transverse 
emargination, as in many species of Berosus; and the base of this emargination is 
slightly prominent in the middle. 
LIMNOCHARIS. 
Limnocharis, Horn, Trans. Am. Ent. Soc. 1872, p. 144. . 
This genus was founded by Dr. Horn fora very minute insect found in the Californian 
mountains ; but its validity as distinct from Limnebius is not quite clear tome. Dr. Horn 
relies for its isolation on the number of ventral segments, which he states to be eight, 
the terminal one being destitute of setee; and he supplements this by alluding to the 
