12 
BULLETIN 1225, U. S. DEPARTMENT OF AGRICULTURE. 
Both in this stage and also in the pupa stage which follows they are 
never seen on the leaves and limbs and can be found only by digging 
into the bark. 
The duration of the prepupal stage is usually very brief, less of the 
life of the thrips being passed in this stage than in any other. Dur- 
ing the warm weather most of the thrips remained in this stage 
only about 24 hours. No specimens in the breeding jars ran over 2 
days. The average for 58 individuals was 1.17 days. During the 
winter months this stage was passed in from 2 to 5 days, with an aver- 
age of 3.5 days. Table 2 gives detailed records on the length of this 
stage. 
PUPA. 
The pupal stage is passed entirely in seclusion in the bark lesions, 
and the pupa? are never seen on the outside of the tree. The thrips in 
this state do not move about but remain quiescent, and do not feed. 
After the final molt the adults emerge from the bark and appear on 
the limbs and buds. 
The pupa stage varied from 1 to 4 days in summer, with an average 
of 2.89 days. In winter it lasted from 2 to 7 days, with an average of 
5.35 days. Even in the colder parts of the State the pupal stage is 
not of very great duration, for the periods of inactivity caused by 
unfavorable weather are passed by hibernation of the adults. 
Table 2. — Duration of larval and pupal stages of the camphor thrips. 
IN SUMMER. 
Record No. 
10 
11 
12 
13 
14 
15 
16 
17 
18 
19 
20 
21 
22 
23 
21 
25..... 
26 
27 
2^ 
30.... 
31.... 
32.... 
33.... 
34.... 
35.... 
36.... 
Date 
hatched. 
1921 
Aug. 11 
...do 
...do 
...do 
...do 
...do 
...do 
...do 
...do 
...do 
Aug. 12 
...do 
...do 
Aug. 13 
..do 
..do 
Aug. 14 
..do 
..do 
..do 
..do 
. ...do 
.l...do 
. ...do 
.[...do 
J Aug. 15 
- ! ...do 
.|...do 
. ...do 
J. ..do 
. ...do 
-[-.-do 
. Aug. 16 
. ...do 
J. ..do 
.l...do 
First instar. 
Date of 
molt. 
1921 
Aug. 16 
Aug. 15 
...do 
...do 
...do 
Aug. 16 
Aug. 15 
...do 
...do 
Aug. 16 
...do 
...do 
Aug. 18 
...do 
...do 
...do 
...do 
...do 
...do..... 
...do 
...do 
Aug. 17 
Aug. 19 
Aug. 18 
...do 
Aug. 19 
...do 
Aug. 18 
Aug. 19 
...do..... 
...do 
...do 
...do..... 
...do..... 
...do..... 
Length 
of 
stage. 
Day*. 
Second instar. 
Prepupa. 
Date of 
molt. 
1921 
Aug. 20 
Aug. 19 
..do.... 
Aug. 20 
Aug. 19 
Aug. 21 
Aug. 19 
..do.... 
..do.... 
Aug. 20 
..do.... 
Aug. 19 
Aug. 20 
Aug. 21 
..do.... 
..do.... 
Aug. 22 
Aug. 23 
Aug. 22 
..do.... 
Aug. 23 
..do.... 
Aug. 21 
Aug. 24 
An-. 22 
..do.... 
Aug. 23 
..do.... 
..do.... 
Aug. 24 
Aug. 23 
Aug. 24 
Aug. 23 
..do.... 
Aug. 24 
Aug. 26 
Le "? th i Date of 
stale. molt " 
Days. 
4 
4 
4 
5 
4 
1921 
Aug. 21 
Aug. 20 
...do.... 
Aug. 21 
Aug. 20 
Aug. 23 
Aug. 21 
Aug. 20 
...do.... 
Aug. 21 
Aug. 22 
Aug. 20 
Aug. 22 
...do 
...do.... 
...do.... 
Aug. 23 
Aug. 24 
Aug. 23 
...do.... 
Aug. 24 
...do.... 
Aug. 22 
Aug. 26 
Aug. 23 
...do.... 
Aug. 24 
...do.... 
...do.... 
Aug. 25 
Aug. 24 
Aug. 25 
Aug. 24 
...do.... 
Aug. 25 
Aug. 28 
Length 
stage. 
Days. 
1 
1 
1 
1 
1 
2 
2 
1 
1 
1 
2 
1 
2 
1 
1 
1 
1 
1 
1 
1 
1 
1 
1 
2 
1 
1 
1 
1 
1 
1 
1 
1 
1 
1 
1 
2 
Pupa. 
Date of 
molt. 
1921 
Aug. 24 
Aug. 23 
Aug. 22 
Aug. 24 
Aug. 23 
Aug. 26 
Aug. 22 
...do 
Aug. 23 
Aug. 24 
..do 
Aug. 23 
Aug. 24 
Aug. 25 
...do 
...do 
Aug. 26 
Aug. 28 
Aug. 26 
...do 
Aug. 28 
Aug. 27 
Aug. 24 
Aug. 28 
Aug. 27 
Aug. 26 
Aug. 27 
Aug. 28 
Aug. 27 
Aug. 28 
Aug. 27 
Aug. 28 
Aug. 27 
...do 
Aug. 28 
Aug. 31 
Length 
of 
stage. 
Days. 
