710 HINTS FOR THE PROMOTION OF ECONOMIC ENTOMOLOGY. 
having a high dip to the eastward owing to the eastward inclination 
of the axis of the folds. At North Adams, in the ridge of slate 
just west of the village, the limestone and slate both dip eastward, 
there being here the north end of one of the inclined synclinals. 
The making of the highest summits of the Taconic region ap- 
pears thence to have depended on this doubling of the folds. It 
becomes exceedingly difficult in such cases to ascertain the true 
thickness of the slate formation. 
In view, then, of the facts stated in my former article with regard 
to the age of the limestone and its overlying rocks, it is not easy 
to avoid the conclusion that the Taconic slates are Hudson river 
slates, as long since held by the Professors Rogers; and, also, 
that the rocks on which Prof. Emmons, in his New York Geologi- 
cal Report, first based his Taconic system, or out of which he de- 
vised it, are after all nothing but the Hudson river and Trenton 
groups, with the underlying Chazy. The Trenton limestone and 
Hudson River or Cincinnati groups, which properly constitute one 
series in American Geological History, are then the true Taconic 
system. 
HINTS FOR THE PROMOTION OF ECONOMIC 
ENTOMOLOGY IN THE UNITED STATES.* 
BY JOHN L. LECONTE, M.D. 
eer cae tse 
Ir is indeed a most gratifying evidence of the increasing in- 
terest in the department of zoology which we cultivate, that the 
entomologists, now in connection with the ‘American Association 
for the Advancement of Science,” are sufficiently numerous to 
form a separate sub-section, and enough in earnest to make the 
meetings of the section of value to attract our widely scattered 
students. 
I hail with joy the opportunity of being present at this meet- 
ing, and the more so, because absence from the country has pre- 
vented me from being with you on previous occasions, when you 
assembled to deliberate on the means necessary for the promotion 
of our favorite science; to communicate to each other that which 
you have done of best during the year, and call on your col- — 
*Read at the Portland Meeting of the Amer. Assoc. Adv. Science. 
