90 Trans. Acad. Sci. of St. Louis 
from the north so that the nest protection conceals the intruder 
until the nest is nearly under foot. But there are many varia- 
tions. Some birds gave distress simulations under many cir- 
cumstances, others gave nothing but casual abandonments. A 
complete graduation between these two reactions, of course, 
existed: the bird would allow close approach at times then leave 
without distress simulation, or fly but stay near and call. The 
unconcerned ‘‘ground picking” was always a sign of an incubat- 
TABLE 14 
protective reactions of an incubating female Prairie Horned Lark 
eae No. Bi, June 20, 1926, Evanston, IIl.). 
Time of Time of Interval Between 
Flushing cig Between Return eturn Reaction 
Female lushings and Flushing 
4:20 a.m 4:30 a.m Casual abandonment 
6:25 2 hours 5 minutes |............ 1 hour 55 minutes | Casual abandonment 
6:35 10 minutes 6:38 Distress simulation 
7:44 1 hour 9 minutes 7:49 1 hour 6 minutes | Casual abandonment 
12:40 p.m. | 4 hours 56 minutes | 12:45 p.m. | 4 hours 51 minutes | Casual abandonment 
3:09 2 hours 29 minutes | 3:14 2 hours 24 minutes | Casual abandonment 
3:20 11 minutes 3:26 6 minutes Casual abandonment 
3:36 16 minutes 3:41 10 minutes Casual abandonment 
3:42 6 minutes 3:45 1 minute Distress simulation 
3:47 5 minutes 3:53 2 minutes Reluctance plus cas- 
. : abando: x narigg 
r 10 minutes 4:01 4 minutes Reluctance plus 
ina : ual aban Fo nical gs 
; 9 minutes 4:11 5 minutes Reluctance plus cas- 
ai : ual abandonment 
: 5 minutes 4:14 0 minute Reluctance rs 
4:14 : soe plus exe 
: 3 minutes 4:17 0 minute Reluctance plus exag- 
= 
4:17 3 minutes 4:20 i tance f 
: 0 minute Reluctance plus exag- 
Sar 
. r i ation. 
4:22 5 minutes 2 minutes Reluctance plus cas- 
is ual abandonment. 
oa 8 minutes 4:35 minutes Casual abandonment 
: 16 minutes 4:53 u minutes Casual abandonment 
5:01 iS hihates © Le, 8 minutes Casual abandonment 
6:30 1 hour 29 minutes |...... Casual abandonment 
cigar 
een ee 
Summary: — of flushings: 20 
eaction when fi time consumed i 4:70 minutes. . 
Reaction flushed imme ae ipeinabe af — to nest: vet 
pian cme when flushed sta ro minute from time of return: distress simulation. 
Reaction w 
leave pies fushed two to five minutes from time of return: reluctance to 
Reaction w when Bushed ive minutes or tore from time of return: normal casual 
