18 THE PERIODICAL CICADA. 
• 
about latitude 38°, but in Illinois one of them ascends between two and 
three degrees above this line, while the 17-year broods descend below it 
in several places, the two races sometimes occurring in the Oarolinas. 
Thus the two races sometimes occupy the same territory; while two 
broods of the same race, appearing in different years, may also overlap 
one another, as in the instance given in the account of Brood XXII, in 
Virginia, where the "locusts" appear every eighth and ninth year. In 
order to make the subject as clear as possible, and to facilitate refer- 
ences, I have retained the numbering of the different broods given in 
1868 in accordance with the sequence of their appearance from and after 
that date. 
Brood I.— Septendecim— 1869, 1886. 
In the year L869, and at intervals of seventeen years thereafter, they will, in all 
probability, appear in the valley of the Connecticut River. According to Dr. Asa 
Fitch (N. Y. Rep., I, p. 40), tliey appeared there in 1S18 and 1835, and according to 
Dr. Smith, they occurred in Franklin, Bristol, and Hampshire Counties, Massachu- 
setts, in 1767, 1784, 1801, 1818, 1835, and 1852. 
1869. — The genuineness of this brood was fully established in 1869, 
as its appearance in Connecticut that year was recorded by several 
different journals {Amer. Entomologist, I, p. 244), and in Massachusetts 
by a recent communication to the publishers of the Scientific American 
from Mr. Guilford H. Hathaway, of Fall Eiver. He observed the Cica- 
das at Freetown, near Fall Kiver, in the years 1818, 1835, 1852, and 
1869, and adds : " In 1818 they were very numerous ; in 1852 still less ; 
and in 1869 they were quite scattering in comparison with 1818." 
Brood II.— Trededm— 1882, 1895. 
In the year 1869 they will, in all probability, appear in Georgia, in Habersham, Ra- 
bun ?, Muscogee, Jasper, Greene, Washington, and adjacent counties, having ap- 
peared there in 1843 and 1856, according to Dr. Smith. 
1869. — True to time, this brood appeared in great numbers, in 1869, 
in the northwestern part of Georgia, as I was informed by Mr. A. E. 
McCutchen, of Lafayette, Walker County, in that State. There is a 
great deal of evidence, however, which goes to show that it is the 17. 
year Brood XXII which occurs in the northeastern counties, and Mr, 
George P. Kollock, of Clarksville, Habersham County, wrote that the 
"locusts" were not therein 1869, but that they swarmed in 1868 and 
1851. This 17-year brood seems to confirm Dr. Fitch's statement (N. 
Y. Eeport, I, p. 40) regarding the extent of his fourth brood, and it is 
further continued by the testimony of Mr. D. C. Sutton, of Lafayette, 
Ga., who wrote me on June 30, 1874, that u the 17-year brood of Haber- 
sham and the northeastern counties occurred in 1868, simultaneously 
with the 13-year brood [XVIII] of Walker County, and the northwest- 
ern part of the State. 
