Department of Agriculture. 
Division of Entomolog-y, 
Washington, 1). (7., May 25, 1885. 
Sir: I have the honor to submit for publication Bulletin Xo. 8 from 
this Division. On account of the concurrence the present year of two 
extensive broods of the Periodical Cicada, the one a 17 year, the other 
a 13-year brood, the inquiries in reference to this insect will be excep- 
tionally numerous, and have, in fact, already begun to reach the De- 
partment. With the view of meeting the demand for information upon 
the subject, and with the further view of soliciting data that will enable 
me to more completely map out the geographical limits of these two 
broods, I have prepared this Bulletiu. It is based upon an article pub- 
lished seventeen years ago, in my First Report on the Insects of Mis- 
souri, and is in fact to be looked upon as a revised edition of that article, 
with the omission of such passages as had but a local or temporary inter- 
est, and the addition of such chronological data as I have accumulated 
during the intervening time. 
Respectfully, 
0. V. RILEY, 
Entomologist. 
Hon. Norman J. Colman. 
Commissioner of Agriculture. 
