C()XT1-;\'TS. 
Pago. 
Suininnry of tho habits and cliaractoristics of tlic ( icada 11 
The races, broods, and varieties of tlie ('ica(hi II 
A 1 7-year race and a 1 3-year race II 
Relation of climate to the races IS 
The dwarf periodical Cicada , 20 
The broods of the periodical Cicada 22 
The oriu:in of the broods 22 
The classification of the broods 25 
The relationship of the different broods 28 
Tne relationship of the 17-year broods 29 
The relationship of the 1 3-year broods 30 
Sources of error in the old records 30 
Broods of 14, 15, or 16 year periods 33 
Future appearances 34 
The distribution of the periodical Cicada 34 
Sources of information 34 
The general range of the species and of the two races 35 
The range of the well-established broods, taken in numerical order 38 
Broods of the 17-year race 38 
Brood l—Septendedm—ldlO 38 
Brood II — Septendedm — 1911 39 
Brood lll—Scptendecim—l^V2 41 
l^rood lY—SepUndcdm—l^n 42 
Brood Y—Septendecim—IS)\A .,. . 43 
Brood VI — Septendedm. — 191 5 44 
Brood YU—Seplende.dm,—\^\Q> ' 40 
Brood VIII — Septendedm — 1917 47 
Brood IX— Septendedm— m?> 49 
Brood X— Septendedm— \S)\S) 50 
Brood Xl—Septendeeim.—WlO 54 
Brood Xll— Septendedm— im\ 55 
Brood Xlll— Septendedm— W22 57 
Brood XIN— Septendedm— IS)2?> 58 
Brood XY— Septendedm— 1^01 00 
Brood X\l— Septendedm— Am?> 02 
Brood XWl—Septcndecwi—nm 03 
Brofxls of the 1 3-year race 05 
Brood XVIII— Trcrfcciwi— 1919. 05 
Brood XIX— Tm/mwi— 1907 00 
Brood XX— Trf^m— 1908 , 08 
Brood XXl—Trededm—nm 08 
Brood XXll—Trededm—l^\0 09 
6 
