604 A Cosmopolitan Butterfly. II. Its History. (October, 
brooded; our E. Comyntas, named for the resemblance to its 
European congener, and by some careless authors considered 
identical with it, is also a wide-spread insect ; but even in New 
England, which is toward the northern limit of its’ range, it is 
triple-brooded. The wide-spread European blues, Argus and 
Aegon, are usually placed among monogoneutic insects, and the 
latter certainly has but a single brood in England (where it is 
the only one of the two found) ; Meyer-Diir is in fact almost the 
only author who claims these species as digoneutic ; both of them 
occur in Southern Europe; the American Scudderit, closely allied 
to these and an insect hardly known south of the Canadian bor- 
der, is double-brooded. Our Pontia Protodice is triple-brooded, 
and the European P. Daplidice only double-brooded, while our 
common species of Eurymus, E. Philodice and E. Eurytheme, 
are triple-brooded in the north (perhaps polygoneutic farther 
south), and the closely allied European species only single or 
double brooded. 
But the most striking example of all will be found in the spe- 
cies of the genus Iphiclides. The European J. Podalirius is con- 
fined to the Mediterranean region, while our J. Ajax belongs to 
the southern half of the United States; the regions are therefore 
fairly comparable ; yet we can find no mention of more than two 
broods of 7. Podalirius, while Mr. Edwards has shown that, even 
as far north as the Appalachian valleys of West Virginia, I. Ajax 
has four and sometimes five generations during the year ; more- 
over, the first of these generations is dimorphic, and the dimor- 
phism has in it the semblance of a seasonal character, the earlier 
individuals being of one type and the later of another. Hs 
These cases might perhaps be multiplied, but further positive 
evidence is not at hand; it should be remarked, however, that 
there is no reversal of this rule; among all the butterflies prop- 
erly comparable on the two continents, there is no single instance 
where the European butterfly has more broods than the Ameri- 
can. 
This result of a comparison of the annual histo 
European and American butterflies furnishes but another instance 
of that intensity which seems to characterize all life in America. 
The expenditure of nervous and vital energy, against which phy- 
sicians vainly inveigh, which superannuates our merchants, ge 
yers, clergymen, and other professional men, is not induced 4 
the simple passion for gain, place, power, or knowledge, ae 
by an uncontrollable restlessness, a constant dissatisfaction W! 
ries of similar 
