vi INTRODUCTION. 
The Arctiide rank next to the Pyralide in point of numbers, 350 species, with 
eighty-two new, being here recorded from Central America. Out of this total, 236 
appear to be peculiar to our region. Most of them are southern forms. 
The Chalcosiide are very poorly represented in the New World. Our four species, 
two of which are treated as new, belong to one genus, all of them being peculiar. 
They appear to mimic species of other families—either Lithosiide or Tortricide. 
The Lithosiide are fairly abundant in Central America, ranking next to the 
Sphingide in the number of species. Of the forty genera enumerated, two are charac- 
terized for the first time; and of the 119 species, fifty-three are described as new. 
Of the species, no fewer than 101 have not as yet been noticed from beyond our 
limits. 
The Melameride are not very numerous in the region here dealt with, their head- 
quarters being in Tropical South America, on the Upper Amazons and in Ecuador. 
Twenty-four genera are enumerated, four of which have been described for the first 
time; and of the sixty-four species, twenty are treated as new, forty-four of the whole 
number being peculiar. None as yet have been recorded from the United States. 
The Dioptide and Liparidz are represented in our region by thirty and fifty-three 
species respectively ; the first-mentioned family by eight genera, three of which are 
described as new, and with twenty-one new species, twenty-seven of the total number | 
being peculiar to Central America. The Liparide include fifty-three species, thirteen 
of which are treated as new, belonging to eighteen genera; two of the species have 
been recorded from the United States, while thirty-six are as yet only known from 
Central America. No species of Dioptide has been noticed from north of Mexico. 
The Saturniidee include many species, most of them being of large size. Of the 
nineteen genera and seventy-four species enumerated, nineteen of the latter are regarded 
as new; forty-seven appear to be peculiar to Central America. These insects are of 
very sluggish habits, and it is possible that additional species may still be discovered. 
The Lasiocampide and Limacodide are both well represented, the former by 113 
and the latter by sixty-four species, with forty-seven and thirty-three new respectively. 
The Lasiocampide belong to twenty-seven, and the Limacodide to twenty-two genera, 
