INTRODUCTION. vil 



largely endemic. The Endomychidse, which I regard as also being a highly evoluted 

 family, but as containing more primitive and generalized genera than the Erotylidae, 

 bear out this view. 



The number of genera of the family EndomychidaB, including the additions to the 

 Munich Catalogue, may be roughly taken as sixty, and the described species as 480. 

 In the volume now completed the genera recorded are fifteen, with eighty-one species, 

 of which four genera and thirty-nine species are new. I have before recorded my 

 conjecture that the smaller and more hairy species, as those of the large genus 

 Stenotarsus, represented a more primitive less evoluted form, and these are found in 

 all parts of the world. 



The large family of the Coccinellidse presents more difficulties on the subject of 

 distribution, from their being, as it appears to me, taken as a whole, of a more 

 generalized type than the two preceding families. 



What strikes one, on studying this group with attention, is the very feeble and 

 trivial characters on which the genera are based, and yet that better ones cannot be 

 found. And this appears from the varying opinions of classifiers as to their adoption 

 in their systems. Thus, while Crotch admits 137 genera for 1340 species, only 

 100 genera are retained in the Munich Catalogue for 1444 species. 



For Central America, as recorded in this volume, 239 species are placed in forty- 

 three genera ; and while of this rather limited number 108 species are apparently 

 new, I have only. ventured to propose three new genera. 



But the species of this family rather readily divide into two sections, according as 

 they are smooth or hairy, and still more so if we take the larger and more important 

 portion of the latter which are phytophagous, and have the mandibles retaining the 

 form adapted for that kind of food. 



One can hardly avoid the conclusion that the Epilachnce are derived from the 

 Phytophagous stirps, not only on account of their food, but of their very close 

 resemblance in many instances to Cassididse, some very closely resembling Chely- 

 morjphw, and others having the metallic lustre of so many of this latter family ; and 

 the singularly convex and inflated form of the elytra in the Coccinellidse, modified, 

 but present, in the JEgithi and true Erotyli, having, as I think, its counterpart in the 

 gibbous and elevated forms of Cassididse. It is not only in their food that the 



