-INTRODUCTION. xix 
derma, Emmenastus (excluding the apterous species), Nyctobates, Nuptis, Phrenapates, 
Platydema, Hapsida, Hegemona, Isaminas, Saziches, Oxidates (Mexico only), Nautes, 
Tarpela, Talanus, Paratenetus, Acropteron, Pyanisia, and Strongylium.  Zopherus, 
Nosoderma, Hegemona, and Osidates, all numerous in species, have their head- 
quarters within our limits. The genera with the largest number of representatives 
are :—<Strongylium (69), Hiewodes (60—all but one restricted to Mexico or north 
thereof), Asida (55—none of which occur south of the Isthmus of Tehuantepec), 
Tarpela (51), Platydema (48), Epitragus (37), Emmenastus (29), and Blapstinus (27). 
Forty-one genera are known only as yet from within the limits of Central America, 
but a number of these are scarcely likely to be endemic: of those that are almost 
certain to extend into the northern part of South America, the following may be 
mentioned :—(@atus, Isicerdes, Daochus, Arrhabeus, Mophon, Moon, and Mentes. 
Seventeen genera (mostly monotypic) are peculiar to Mexico, one to Honduras, two to 
Guatemala, one to Nicaragua, two to Costa Rica, and three to the State of Panama. 
Of the seventeen Mexican genera, only three or four, at most, are likely to extend into 
the United States, and as they have not been found in Guatemala or southwards, it is 
almost certain that the majority of them are really endemic; two of these, Oxidates 
and Mitys, each contain several species of large size. ‘Twenty-seven genera are common 
to North, Central, and South America, twenty-eight to North and Central America 
(chiefly Mexico), and forty-two to Central and South America. One genus, Hnnebeus 
(group Diaperides), has a most remarkable geographical distribution, viz. :—Central 
America, Colombia, and Tasmania, with two, one, and one species respectively, all very 
closely allied: the only parallel case in the Heteromera known to me being Peleco- 
tomoides (Rhipid ophoride), closely allied species of which inhabit Tropical America 
and Australia. 
The family Cistelide, which may be described as degraded Tenebrionide with 
pectinate tarsal claws, is very numerous in species in Mexico and Guatemala, but 
diminishes in numbers southward. From within our limits 158 species are enumerated, 
belonging to twenty-four genera, of which no fewer than fifteen genera and 150 species 
are described as new. ‘This is one of the ‘neglected’ families of Heteromerous 
Coleoptera, and up to the date of publication of this work not a single species had 
been recorded from within our limits. No attempt had hitherto been made to deal 
with the Cistelid-fauna of any region, except that of Europe and of North America, 
and a large number of new generic names were required for the Central-American 
species. The Cistelide, as a whole, are more numerous in temperate than in tropical 
c2 
