56 PLANT-BUGS INJURIOUS TO COTTON BOLLS. 
estimates which have already been referred to placed the number of 
conchuelas on the entire tabla at about 60,000. At the rate of one boll 
destroyed for each three-fourths of a day, it may be calculated that 
on July 15 the bugs had been in the field an average of 16 days each. 
Estimates made after December 1, the details of which will be 
found elsewhere, placed the destruction by bugs in Ceceda A, tabla 14, 
at approximately 28 bales, not taking into consideration the bolls 
which were shed from the plants as a result of injury by these insects. 
The estimate of 60,000 conchuelas in the entire tabla was based on 
data obtained on July 15, after which there was a slight increase. 
Reference to Table XXVI will show that an estimate of 65,000 bugs 
is not too high for the maximum number of live conchuelas in this 
tabla at any time in July. For each 2,300 bugs, therefore, about one 
bale of cotton was destroyed. Considering the loss of one bale of 
cotton as equivalent to the moderate sum of $45, on the average each 
bug in the tabla destroyed cotton to the value of about 2 cents. This 
estimate can not be considered as representing even approximately 
the amount of damage by a single conchuela except under conditions 
similar to those described. General deductions of wider application 
may, however, be drawn from the data given. 
From a comparison of the average maximum and minimum num- 
ber of punctures per damaged boll in Ceceda A, tabla 14 (Table XXV), 
it is evident that the bolls were much fed upon by the bugs after they 
had received sufficient injury to result in complete destruction. 
Fortunately such feeding prevents a maximum amount of damage. 
The average of the ruined bolls of the various sizes with the minimum 
number of punctures is 15.4, or about one-third of the average num- 
ber of punctures for all bolls. Even this number is greater than 
usually necessary for the destruction of bolls, as the data given show. 
On the other hand, many punctures are made in bolls which have 
reached such a stage of maturity that there results either no appre- 
ciable damage or only a staining of the lint to a greater or less degree. 
The habit of the conchuelas of congregating on individual plants 
and even on individual bolls has a tendency to result in an excess of 
feeding punctures above the number necessary to cause destruction. 
Data have been given in Table III showing that at Dallas, Tex., in a 
field where plant-bugs were less abundant than in Ceceda A, tabla 14, 
at Tlahualilo, the average number of punctures per destroyed boll 
was 28. For convenience we may suppose that in a field infested by 
the conchuela, where the damaged bolls average 28 punctures per 
boll, it is desired to estimate the amount of damage the individual 
bugs may accomplish. At the average rate of 56 punctures per day, 
which is the estimated number, the bugs would have averaged 2 
