vi INTRODUCTION. 



The Throscidaj (or Trixagidae), at the present time (1897), include about 160 

 described species from all parts. Of this number, forty-three species, belonging to 

 four genera, are recorded by Dr. Horn from within our limits, one genus and eighteen 

 species being characterized as new. One species is added in the Appendix. America 

 north of Mexico has eighteen species and three genera of this family. 



The Eucnemidae is a widely distributed Family, with a total number of about 475 

 species and ninety genera (1890). Dr. Horn enumerates 108 species, belonging to 

 thirty-two genera, from Central America, six genera and fifty-six species being treated 

 as new. Two genera and five species (three new) are added in the Appendix. Some 

 remarks on the geographical distribution of the American genera are given on p. 210. 

 America north of Mexico has (Henshaw, 1895) fifty-seven species and twenty-three 

 genera of this family. Most of the species are very rare in collections. 



The Elateridse, another very extensive Family of Coleoptera, is apparently not so 



numerous in species (taking the whole world) as the Buprestida?, but includes a much 



greater number of genera ; the disproportion in the numbers of the described species 



of the two Families is, however, illusory, and entirely due to the fact that the brilliantly 



coloured Buprestidse are much greater favourites with collectors. The total number 



of species from all parts is given by Dr. Candeze (1891) as 3960, belonging to 238 



genera. The number of species here enumerated from Central America is 531, 290 of 



which are described as new, these belonging to sixty-seven genera, with nine new. 



America north of Mexico has about 500 species (Henshaw, 1895), with fifty genera. 



This Family having been exhaustively monographed by Dr. E. Candeze, it was to be 



expected that most of the conspicuous forms would be known ; nevertheless, amongst 



the smaller species a great deal had to be done. The genera most numerous in species 



within our limits are — Iscliiodontus (45), Agriotes (39), Chalcolepidius (33), Mono- 



crepidius (32), JEolus, (30), Anopliscliius and Glyphonyx (each 23), Horistonotus (20), 



Hemicrepidius (19), and Pyrophorus and Anchastus (each 16). Apart from these, the 



most characteristic are Tomocephalus, Physorhinus, ffypodesis, and Psiloniscus. Oistus 



and Dodecactenns, each containing two or three conspicuous species, are peculiar to 



Central America. Semiotics, Pyrophorus, Pomachilius, and Cardiorhiniis, each containing 



a large number of species in Tropical South America (80, 85, 54, and 36 species 



respectively), are poorly represented within our limits (the numbers being 9, 16, 2, 



and 1), and Cosmesus (with 4 9 South-American species) is entirely absent. Chalcolepidius, 



the giants of the family in America, on the other hand, has its headquarters, as it 



