458 HETEROMERA. 
rounded and forming a continuous outline with the prothorax, finely, densely, and confusedly punctured, 
with rows of very fine punctures towards the base only, the punctures scarcely distinguishable from those 
of the interstices, the latter perfectly flat; beneath and the epipleure finely and closely punctured, the 
metasternum coarsely and sparsely so; prosternum rather broad and convex between the coxa; meso- 
sternum feebly convex, rounded off in front; legs long and slender, fusco-ferruginous, the tibia similar in 
both sexes; the first joint of the hind tarsi shorter than the following joints united. 
g¢. Abdomen with a short (but hidden) sixth ventral segment, the segment without lateral lobes; the 
central sheath stout, gradually acuminate towards the apex, the pieces on either side very short. 
Length 73-9 millim.; breadth 33-43 millim. (¢ 9.) 
Hab. Mrxico, Oaxaca (Sallé), Cerro de Plumas, Almolonga, Chilpancingo, Vera 
Cruz (Hoge); GuatemaLa, Zapote (Champion). 
Numerous examples from Zapote, one or two only from each of the other localities. 
This species may be identified by the confused punctuation of the elytra; in two of the 
Mexican examples the upper surface is rather more densely punctured and in conse- 
quence duller. The North-American J. valida is apparently an ally of this insect. 
2. Isomira subenea. (Tab. XXI. fig. 4.) 
Oblong ovate, rather depressed, brownish-piceous with an eneous tint, slightly shining, clothed with short 
pubescence. Head closely and somewhat coarsely punctured, with the transverse frontal groove deep ; 
eyes rather small; antenne fusco-ferruginous, rather slender in both sexes, reaching in the male nearly 
to the middle, in the female to the first third, of the elytra, joints 8 and 4 equal in length, 4-10 a 
little widened towards their apex and with their inner apical angle rounded in both sexes; prothorax 
short, strongly transverse, the sides converging from a little before the base and somewhat rounded 
behind, the hind angles obtuse, the basal foves very shallow, the disc with traces of a smooth central 
slightly impressed line, the base feebly bisinuate, the surface very closely and finely punctured; scutellum 
closely and finely punctured; elytra widest a little beyond the middle, with rows of very fine oblong 
punctures which in the apical third are confused with and indistinguishable from those of the interstices, 
the latter quite flat and closely and finely punctured; beneath closely and finely punctured, the meta- 
sternum more sparsely and more coarsely so; prosternum narrow ; legs long and slender, fusco-ferruginous, 
the tarsi similar in both sexes. 
g. Abdomen with a short but hidden sixth ventral segment, the segment without lateral lobes: the 
central sheath stout, laterally compressed, the pieces on either side of it stout and rounded off in front. 
Length 63-84 millim. ; breadth 3-33 millim. 
Hab. Mexico, Ostuncalco 7500 feet, Totonicapam 9000 feet (Champion). 
Three examples, captured in the elevated Los Altos region of Guatemala. Resembles 
Cistela fragilicornis, but smaller, the thorax rounded at the sides behind (not con- 
verging from the extreme base), the elytra (as in L. obsoleta) merely with rows of very 
fine punctures from the base to a little beyond the middle, the antenne with much less 
elongate joints, &c. The single male example (from Totonicapam) is much smaller 
than the others. 
8. Isomira evanescens. 
Oblong ovate, feebly convex, reddish- or piceous-brown, slightly shining, the elytra with a very slight «neous 
tinge, thickly pubescent. Head closely and finely punctured; eyes rather small, more widely separated 
in the female; antennee comparatively short, slender, and similar in both sexes, not reaching to the 
