307 
•*Egg teds ranged in size from I /2 acre to 200 acres, with an average 
of approximately 15 acres per egg ted for' .the D. longipennis area. The 
average egg pod population of 75 "beds ranged from 0.7 pod to 20 pods per 
square foot, with an average of nearly 5.8 pods per square foot. The first 
hatching dates for D. longipennis .' together with the average duration of 
the hatching period, are shown for each of the major D. longipennis States 
in tatle 7, 
Tatle 7.-* 4il&te« af. batching nerioda ftr Uev Mexico^ 
Texas, and Colorado in 1939 
state 
Eirst 
hatch 
Hatching 
complete 
Average duration of 
hatching period 
New Mexico 
April 21 
June 5 
Days 
23 
Texas 
April 22 
May 30 
23 
Colorado - - - — 
May 2 
June 1 
18 
"The duration of the hatching period for individual teds ranged from 
11 to 30 days. The shorter average hatching period of 18 days for Colorado 
compared v;ith 23 days for New Mexico and Texas is attributed to weather. 
Eggs began to hatch at a number of teds in the two last-named States as the 
result of ari unseasonably warm spell, during the latter part of April; then 
followed cool weather in the first half of May, which prolonged the hatch- 
ing period. Hatching was deferred on a number of beds; in Colorado by the 
same cool spell until warm weather prevailed, when a quick hatch resulted. 
Egg beds at lower altitudes, in warm exposures, began to hatch 19 days 
earlier than did some of the beds situated less favorably on high mesas. 
An egg bed in Lincoln .County, Colo., which had both a southern and a 
northern exposure, exemplifies the effect of a favorable location. When 
hatching was complete on the southern slope of this bed, only 55 percent 
of the eggs had hatched on the northern exposure. 
"The proportion of liable eggs for all the beds was large,- and the 
few eggs which did not hatch constituted only 1 percent or less. The 
length of the nymphal period for D. longinennis is shown in table 8. The 
time interval is measured from the first hatching to the first appearance 
of adults. 
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