THE CONCHUELA. 
57 
bolls per day destroyed instead of 1 ] bolls per day estimated in 
Ceceda A, tabla 14. As the percentage of damaged bolls increased, 
the daily damage per bug would diminish. If the increase in the 
number of new bolls was sufficient to prevent an actual increase in 
percentage of damaged bolls, the average daily injury for each bug 
would remain fairly constant at 2 bolls per day, and the ultimate 
damage, if in the same ratio as that which obtained at Tlahualilo in 
the field, to which the data refer, would be 60 per cent more than 
estimated for that field, or an equivalent of 3 J cents for each bug. 
From estimates made at Tlahualilo on the numerical status of 
the insects in July and on the percentages of ruined bolls in December, 
the relationship of the number of bugs present during the period of 
maximum abundance and the damage accomplished during the 
season may be presented in tabular form as follows: 
Table XXVI. — Relation of number ofconchuelas to amount of damage. 
Field. 
Zaragoza B, tabla 1. east quarter. 
Zaragoza B, tabla 3, west quarter 
Ceceda A, tabla 14, west quarter , 
Number of 
adult eon- 
chuelasper 
100 plauts, 
Julv 23-25, 
1905. 
9.G 
1.7 
46 
Number of Average 
adult con- number of 
cbuelas per bales good 
row, Julv cotton per 
23-25, 1905. acre. 
30 
Average 
number of 
bales 
ruined 
cotton per 
acre. 
Percentage 
of ruined 
cotton. 
0. 412 , 
.644 
.210 
0.246 
.11 
.221 
The percentage of injury in Ceceda A, tabla 14. is so far above the 
ordinary that it may be properly considered as representing an 
extreme case, while the individual conchuelas, for reasons given. 
accomplished a minimum amount of damage, equivalent to about 
2 cents. The maximum amount of damage for the individual con- 
chuelas would be difficult to determine without a long continued 
series of observations, but it is probably equivalent to not more 
than 2 or 3 cents above the minimum amount. These estimates, 
while necessarily only approximating actual conditions, will serve to 
give a general idea of the damage an individual conchuela or other 
plant-bug is capable of causing. A knowledge of this point is an 
essential step in the determinatioD of the practicability of various 
remedial measures. 
REDUCTION IN YIELD OP INFESTED COTTON FIELDS. 
As has been stated, the estimated loss to the cotton crop o{ 1903 
at Tlahualilo was between 1,200 and 1,500 bales. Accordingly this 
loss for the entire acreage in planted cotton— amounting to about 
