556 
JOURNAL OF ECONOMIC ENTOMOLOGY 
[Vol. 17 
pressed areas. These depressions are in four more or less confluent 
longitudinal series which are more marked on the posterior half of the 
body. The darker color of the insect showing through the mealy cover¬ 
ing at these spots produces a distinct symetrical pattern.” Ferris (4) 
also calls attention to the “longitudinal rows of impressed dots” as 
being “quite distinctive.” It is this “distinct symmetrical pattern” to¬ 
gether, as stated by Green, with the “claret colored liquid in round drops, 
two close to the head and two close to the tail end, exuded by the insect 
when irritated” which makes its determination in the field a rather 
simple matter in the adult stage. 
Distribution and Means of Spread 
While without doubt, wind and birds are important factors in the 
spread of this pest, particularly at the time of the peak hatch in the 
spring, when the minute young are moving freely in the trees in count¬ 
less numbers, the more probable avenues of spread are through contacts 
made during cultural operations and the handling of the fruit in the 
field, particularly as community or association labor crews are in general 
use. The loose cottony egg masses as well as the freely moving indi¬ 
viduals are easily carried on the clothing of orchard workers or on the 
cultural equipment and the migratory habit of the adult female in 
searching for a place for oviposition makes the field box an easy carrier 
from orchard to orchard. 
Realizing the seriousness of these avenues of spread the Horticultural 
Officials in the infested counties have made every effort to control the 
movement of laborers and equipment between infested and clean or¬ 
chards. Fumigation of all field boxes before leaving the packing house 
has been required. Laborers have been supplied with clean caps, jackets, 
coveralls, gloves and other equipment after leaving infested orchards 
and before entering clean ones. In many cases owners of infested or¬ 
chards in comparatively free areas have been required to handle their fruit 
through packing houses in generally infested areas. In spite of all of 
these precautions however, the spread has been persistent, particularly 
in the coastal areas. It is entirely possible that in many cases establish¬ 
ment took place in .unobservable quantities before its presence in the 
south was detected and attempts made to check its spread. 
While Clausen (2) recorded less than ten acres at Uplands as being 
infested in 1915, Woglum (6) shows 600 acres infested in that same area 
in 1918, in 1922 this had increased to over 1000 acres and a spread was 
recorded into the adjacent counties of Riverside and Los Angeles. In 
