Aug. I, X92I 
Biological Study of Red Date-Palm Scale 
665 
spiral on the bole of the palm. The fruit stems come out from behind 
the leaf bases in a definite area around the bole each year. 
August, 1919. Fruit stems of current year (1919) heavily infested with immature 
and mature. (wine-red) stages. Leaf bases above (first two) show rapid decrease 
(almost clean) in amount of scale of similar development. Leaf bases (third, fourth, 
fifth) below fruit stem with increasing amounts of old brown and bronze-colored scales, 
but still some living immature and mature forms. 
Fruit stems of 1918 dead and brown but covered at base with old dead scales. Leaf 
bases below with small margins of scales in all stages of development but decreasing 
in quantity. 
November, 1919. Condition similar to that noted above but with increased amount 
of scale mass and more reaching brown stage. 
April, 1920. (Migratory period beginning.) 
Fruit stems of current year (1920) with only few (migratory forms) on outside of 
bases of spathe. . 
First leaf base above clean. 
First leaf base below clean. 
Second leaf base below with only a few very young scales in fiber. 
Third leaf base below with young (migrating) forms settling. 
Fourth leaf base below with young and a few mature (wine-colored) forms. 
Fifth leaf base below heavily infested with wine-colored forms and with a few brown 
ones. 
Fruit stem of 1919 heavily infested in all stages, mostly brown and bronze. 
June 2, 1920. (Migratory period about over.) 
Fruit stems of current year (1920) lightly infested from 6 to 18 inches from base 
with immature scales.. 
First leaf base above clean. 
First leaf base below lightly infested with immature forms. 
Second leaf base below lightly infested with immature and wine-colored forms. 
Third leaf base below with medium infestation; some brown scales but mostly 
wine-colored and immature forms. 
Fourth leaf base below heavily infested with brown and wine-colored forms, some 
immature at lower margin. 
Fifth leaf base below heavily infested, all brown, mostly dead. 
Fruit stems of 1919 heavily infested, all brown, dead. 
NATURAL ENEMIES 
Apparently there are few natural enemies of the red date-palm scale. 
Of greatest importance is the little beetle identified by Mr. E. A. Schwarz 
as Laemophloeus ( Cryptolestes) truncatus Casey ( ?) found working through¬ 
out the year on the heavier infestations in the Mecca gardens. Occa¬ 
sionally definite galleries of destroyed scales were noted where these 
beetles were working. This beetle was also found feeding on the scdles 
out on the fruit clusters in a commercial garden during the latter part 
of April. 
In January, 1920, a number of orange-pink dipterous larvae, possibly 
those of some species of Itonididae, were found under a leaf base in the 
midst of a mass of scale insects. 
