662 
Journal of Agricultural Research 
Vol. XXI, No. 9 
male, 0.4 mm. long, is very active and moves about much more quickly 
than the female larva. The number of adult males in proportion to adult 
females is exceedingly small. Throughout the year, in examining over 
300 larvae and cocoons, the writer found as many as 30 male pupae but 
only 8 adult males. 
NATURE OF INFESTATION. 
The main infestation of scales on a mature palm (PI. 127) is found on 
the white living tissues of the leaf bases and fiber bands from 1% to 3 
feet down from the crown, or from the fifth to tenth leaf whorl (PI. 128). 
Both inner and outer surfaces are usually infested, and the area may be 
from X inch to 5 inches in width. The scales will be massed together, 
often in more or less definite order and frequently several layers deep. 
Infestations of lesser severity will continue 011 the living tissues of the 
old leaf bases and fiber bands even to the ground, but as the margin of 
living tissue narrows the quantity of living scales becomes appreciably 
less. These insects are usually buried to a depth of 4 or 5 inches 
under the plant tissues; and as the fiber bands and leaf bases are ex¬ 
ceedingly tight, the scale is well protected from heat, dry atmosphere, 
or control measures. Due to the rapid growth of the palm and definite 
migratory habit of the scale, the crown of the tree for from three to five 
leaf whorls, depending upon its size and growth, is kept free of scales. 
This has been proved by cutting open the crowns of several palms and 
offshoots. During the greater part of the year (July to April) practically 
all of the scales are found on the leaf and fiber bases and the fruit stems. 
The small number found out in the leaf pinnae are usually of little im¬ 
portance. 
That the fruit stems of the current year are found in the area of the 
main infestation and are tender and succulent at their base explains in 
part why they are invariably so heavily infested. A number of fruit 
stems have been removed which were completely massed with scales }i 
inch thick for a distance of from 6 to 18 inches up from the base. Such 
infestations seriously injure the development of the fruit. Another im¬ 
portant factor is that the fruit stem spathes open and the tender young 
stem is exposed at the same time that the so-called “spring migratory 
period” of the scale takes place, thus insuring a complete infestation of 
that tissue. The buds for the blossoms are laid down deep under the 
leaf bases in July to September. The bud growth continues through the 
fall and winter and the spathe pushes out in the spring. Flowering occurs 
in early April, or late April and early May, depending upon the season 
and plant variation. Young palms often show greater variation. It is 
during April, May, and part of June that the greatest migratory period 
of the scale occurs and the exposed fruit stems become infested. The 
progress of this infestation was definitely traced during April, May, and 
