THE COXCHUJXA. 
51 
Bugs were picked from the plants on this tabid between the exam- 
inations of July 11 and 15 and again between the examinations of 
July 27 and 2<J, the first pickings averaging about 7 per row and the 
second averaging between 5 and 10. The removal of these may be 
taken into consideration, although affecting the general results but 
little. The data obtained by these examinations show that con- 
chuelas, or in a broader sense the Pentatomids, reached their maxi- 
mum numbers in this field about July 20, and during the following 
week there was a decrease of nearly 50 per cent. Considering the 
picking just previous to the last examination, a continuance of the 
natural decrease in numbers is evident. 
Following the same general plan, four additional examinations 
were made on July 15 for the purpose of showing the numerical status 
of the bugs on that date throughout the tabla. The length of the 
tabid being about one and one-quarter miles, five examinations were 
made, one at each end and three between, at places estimated to 
divide the tabla into fourths. Table XXII shows the data obtained 
by these examinations. 
Table XXII. — Numerical status of Pentatomid bugs in field of 120 acres, July 15. 1905. 
Examination 
No. 
Number 
of plants 
in row. 
Number 
of plants 
infested 
bv adults 
per 100. 
Number of 
adults P. 
ligata per 
100 plants. 
Number of 
nymphs P. 
ligata on 
100 plants.^ 
Number of 
adults P. 
sayi per 
100 plants. 
Number of 
adults Thy- 
anta sp. 
per 100 
plants. 
Total adult 
Pentato- 
mids per 
100 plants. 
1 
99 
J2 
103 
127 
5 
30 
- 
17 
5.5 
12.5 
52 
57 
33 
7.8 
21.4 
1 3 3< 
92 1* 


3 
8 



2 
2 
1 
1 
1 
57 
34 
8.8 
-. - 
2 
3 
4 
5 
Total 
Average.. 
4' : 
93.4 
91 
In. 2 
171 
34.2 
16 
3.4 
11 
2.2 
7 
1.4 
189 
a Small figures indicate the insiars. 
As there were nearly 1,660 rows in the above tabla, it may be esti- 
mated from the data given that there were on July 15 approximately 
60,000 conchuelas in the entire area of 120 acre-. 
Another series of observations made in plantd cotton inZaragoza B, 
tdblas l-<), also shows a diminution of the pest during the last 10 days 
of July. A single row was examined on each tabid about 200 yards 
from the east end, the 1 rows running north and south. 
