120 THE PERIODICAL CICADA, 
able; hairy armature of legs more distinctly outlined; a row of small 
spines on either side of middle and hind tibiz, while the rows of bristles 
on the inner margins of the anterior femora and tibiz for holding the 
excavated earth are well developed. Anterior tarsus reduced to a mere 
tapering spur about two and one-half times as long as wide at base. 
The femoral comb has one additional tooth, making four in all, count- 
ing the blunt upper 
one (fig. 49). The an- 
tennal joints decrease 
in length from the 
basal to the terminal, 
the basal two and the 
terminal two _ being, 
Fig. 49.—Third larval stage: a, anterior leg, outer face; b, same, however. of nearly 
inner face. (Author’s illustration.) } . 
equal length, respec- 
tively. The wing cases are foreshadowed by minute pads. Sexual 
differences very faintly discernible. 
The larva is in this stage at the completion of the fourth year of its 
existence. 
Fourth larval stage.-—Length, 10 to 15 mm.; anterior femora, 2.40 
mm.; anterior tibiz, 2.70 
mm.; hind tibizw, 4 mm. 
Eye-spots reduced to 
from three to six minute 
black points, rows of 
hairs on head easily dis- 
cernible and prominent; 
spines on femora and 
tibize of all legs, and par- 
ticularly the anterior 
pair, more numerous and 
longer and stouter than 
in the preceding stages. 
The anterior tibia has a 
small tooth within the 
larger blunt subapical 
one. The femoral comb 
has again an additional Fia. 50.—Fourth larval stage: a, full grown larva, muchen- 
tooth. making five in all. larged; b, outline of femoral coms, Cc, anterior leg, outer face; 
) 3 d, same, inner face. (Author’s illustration.) 
Antenne as in the preced- 
ing stage. Rudimentary wing cases somewhat more prominent than 
in the last stage, but still inconspicuous. (See fig. 50.) 
The larva is in this stage at the completion of the eighth year of its 
existence, and the stage probably lasts three or four years. 
AMTARASANS 
