238 THE CANADIAN ENTOMOLOGIST. 



within our territory, while the study of the West Indian, Mexican and 

 South American faunae is one to which the North American student of 

 our moths must sooner or later betake himself, if for no better reason than 

 that it is necessary for a better knowledge of his own particular fauna, 

 which stands in close relationship to these and takes no note of political 

 boundaries. Already I hear of one good student, Mr. Wm. Schaus, work- 

 ing away in Mexico ! 



Very instructive tables may be prepared of the different expression of 

 European and American genera of moths. We have, for instance, more 

 than double the number of species found in Europe of the genera. Apafe/a, 

 Oncocnemis, Catocala, etc. In fact, going parallel with our larger terri- 

 tory, all the principal genera of Moths represented on either side of the 

 Atlantic contain a larger number of American than of European forms ; 

 and this with but few exceptions, such as Eupethecia, where the American 

 species are probably but indifferently known. Certain genera, very largely 

 represented in Europe in the Moths just as in the Butterflies, are totally 

 wanting in America, as, for instance, Zygaena. I am speaking now of 

 peculiar genera which give a determinative expression to the faunae, leav- 

 ing out of sight the innumerable cases of nearly allied genera replacing 

 each other on the two hemispheres. The time for the institution of such 

 comparisons will not fully come until our Western faunae are well known. 

 So important an European genus as Hypopta has only been recently dis- 

 covered in Arizona, and undoubtedly we have yet much to learn before 

 we really know what forms our territory harbors. Quite unexpectedly 

 Prof. Snow found in New Mexico a species, Halisidota trigona Grote, 

 which has an exceedingly close ally in South America, figured by Dr. 

 Herrich-Schaeffer. But what was to me a most surprising fact was the 

 discovery, by Mr. W. W. Hill, of Albany, N. Y., of Hepialus auratus 

 Grote in the North Woods. This species belongs to the genus or sub- 

 genus Phisiodes of Herrich-Schaeffer, and our species has a near ally in 

 Brazil as illustrated by this authority. That such a genus as Hepialus 

 should be so widely distributed, considering its life history, structure and 

 habits, is a proof of the great age of this type of the Moths. Other Bom- 

 bycidae might easily spread themselves, but the Ghost Moths would seem 

 by their weak structure, somewhat unwieldy flight and nocturnal habit, not 

 to be of this number. H. auratus has patches of dead gold scales prin- 

 cipally about the cell of primaries at base, while three bright, gilded, tri- 



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