RANGE OF BROODS IN ORDER OF FUTURE APPEARANCES. 45 
The localities in Pennsylvania dated from 1893, and additions were 
also obtained for Maryland, Virginia, and North Carolina. 1 
The distribution, by States and counties, is as follows: 
Colorado. — Cheyenne Canyon I 
District of Columbia. — North of Washington. 
Illinois. — Madison (?). 
Indiana. — Knox, Posey. Sullivan. 
Kansas. — Dickinson. Leavenworth. 
Kentucky. — Trimble. 
Maryland. — Prince George, south half of St. Mary. 
North Carolina. — From Raleigh, Wake County, to northern line of State; Davie. 
Cabarrus, Iredell, Rowan. Surry. 
Pennsylvania. — Adams, Cumberland, Franklin. 
Virginia. — From Petersburg, Dinwiddie County, to southern line of State; Bed- 
ford, Rockbridge; valley from Potomac to Tennessee and North Carolina bonndary. 
Brood VI.— Tredecim— 1910. (Fig. 15. I 
This L'3-year brood, which appeared last in 1897, is of small extent. 
but well established by many reliable records, the oldest of which 
dates back to 180G. It is Brood IV of Walsh-Riley. 
A summary of the distribution of this brood was given by Mr. 
Schwarz in Circular Ko. 22 of this Division, issued in May, 1897. This 
inquiry resulted in the report of but one additional locality. The dis- 
tribution and relationship of this brood is given by Mr. Schwarz in the 
circular referred to, as follows : 
It is confined to parts of southern Mississippi and adjacent parts of Louisiana 
east of the Mississippi, the particular localities being given further on. Dr. D. L. 
Phares, of Woodville, Miss., has taken particular pains to ascertain the extent of 
this brood, and his lucid and concise account, already published in 1885, in Bulletin 
8 (first series) of this Division, is herewith reproduced: 
"Their western limit is the Mississippi River, the southern about 8 miles north 
of Baton Rouge, the eastern about 4 miles west of Greensburg, the county seat of 
Helena, and 4 miles west also of Liberty, in Amite County. Miss., thus extending 
from 15 to 50 miles from the Mississippi River, and from the vicinity of Baton Rouge, 
108 miles to the northern limit of Claiborne County, Miss., perhaps even farther. 
They therefore occupy East and West Feliciana, the northern part of East Baton 
Rouge, the northwest corner of Livingston and the western part «>t' St. Helena par- 
ishes, La., and Wilkinson, Adams, Jefferson, Claiborne, and parts of Amite, Frank- 
lin, and possibly parts of one or more counties in Mississippi. 
''The reports received since 1885 are mostly confirmatory of Dr. Ph area's statement. 
but Mr. Thomas F. Anderson, of St. Helena, La., writes us that the parishes, or at 
least parts of the parishes, of Tangipahoa, Washington, and St. Tammany had to 
be added to the range of this brood. His statement is quite definite; still a confir- 
mation of these new localities is desirable. 
"Brood VI is evidently a forerunner of the very large 13-jear Brood VII, which 
will appear in 185>8 in the Mississippi Valley. The geographical range of Brood VI] 
was mapped out in the Annual Report of this Department for 1885, and it will be 
'A correspondent (Mr. H.J. (biddings, of Iowa), writing under date October 6, 1898, 
reports that during June of that year he found the periodical Cicada to be quite 
common. In his reply Professor Riley was inclined to consider these specimens a-^ 
precursors of Brood XI. but if so they established a new locality for the brood sec 
Insect Life. Vol. V, p. 200). 
