12 Farmers’ Bulletin 1261. 
Fic. 7.—The avocado white fly: Sooty-mold fungus on upper 
surface of avocado leaf. 
3 Protopulvinaria pyriformis Ckll, 
with a spray rod 
than with a spray 
gun. Where two ap- 
plications of oil 
emulsion are made 
for the white fly, and 
the spray is directed 
toward the twigs 
and branches which 
are infested with the 
scale, it will usually 
not be necessary to 
make an additional 
spray for the dictyo- 
spermum scale, pro- 
vided the branches 
are well covered. 
THE PYRIFORM 
SCALE. 
Another scale in- 
sect found occasion- 
ally on the avocado 
in Florida is the py- 
riform scale. The 
adult female scale 
(fig. 9), the stage 
which is usually ob- 
served on the foli- 
age, is slightly con- 
vex, pyriform (pear 
shaped) in outline, 
transversely corru- 
gated, of a reddish 
brown color, and 
about 3 millimeters 
(one-eighth inch) in 
length. The cottony 
matter projecting 
about the margin of 
the scale consists of 
curled waxy fila- 
ments. Among the 
