23 



history and habits ai-e the same as those of the long scale. The purple 

 scale is not limited to citrus fruits, but occurs also on many other 

 plants. 



Fig. 11. — Purple .scale {Mytilaspis dtricola) , show- 

 ing different stages of male: a, fnlly developed 

 male scale; b, same inverted, showing male 

 pupa within; c, propupa; d, final pupal stage; 

 r, mature winged insect; /, foot of same much 

 enlarged— all greatly enlarged (original). 



Fig. 12. — Purple scale (Mytilaspis cUHcola), illas- 

 trating the formation of the scale covering' a, 

 newly hatched young, with enlarged antennae at 

 left and leg at right; 6, side view of forming scale; 

 (•,same from above — all greatly enlarged (origi- 

 nal). 



Neither the gas treatment nor any of the washes is a certain remedy 

 for this scale, except in the immature stages. Occasionally a very 

 strong treatment will kill the eggs, but it is usually necessary to 

 repeat the application 



once or twice at inter- /^ 



vals of two or three e. 



weeks to effect anything 

 like extermination. 



Tlie Red Scale of Florida. 



This is another scale 

 insect {Aspidiotns Jious 

 Aslmiead) of world-wide 

 distribution. As an or- 

 ange scale it is not a 

 very serious pest on trees 

 grown out of doors, but 

 on trees grown in con- 

 serv^atories or under glass 

 it is very apt to thickh' 

 infest the leaves and 

 fruit. It has a ver}^ wide 

 range of food plants and 

 is one of the commonest of scale insects. 



Fig. 13. — Florida red scale {Aspidiotus ficus): a, leaves covered 

 with the male and female scales — natural size; 6, newly 

 hatched insect with enlargements of antennae and leg; c, d, 

 <\ f, different stages in the development of the female insect, 

 drawn to the s§me scale; g, adult male scale — .similarly 

 enlarged (original). 



This and the following 

 species differ from the M3'tilaspis scales in being nearly circular in 

 general outline, with the molted skins in the center of the scale instead 

 of at the small end (fig. 13). The color of this scale is a rich reddish 



172 



