552 



CITRUS FRUITS AND THEIR CULTURE. 



In Florida the two-spotted ladybug is an effective 

 enemy of scale insects. The ladybugs are very common 



throughout the State. The pupa? 

 are shown in Fig. 123. One 

 mature insect is shown on the 

 right of the twig near its base. 

 Both the larvae and the mature 

 insects feed upon scale insects. 



The Hemispherical scale in 

 Florida is usually held in check 

 by internal parasites of the order 

 Hymenaptera. Insects of the 

 same class usually destroy the 

 green lice or plant lice (Aphis) 

 which frequently infest the new 

 growth on citrus trees. The 

 appearance of the parasitized 

 plant lice is well shown in Fig. 

 124. The bodies of the aphids 

 are congested, swollen and globu- 

 lar. The minute openings, from 

 which the parasites emerge after 



having matured inside the bodies of the aphids, are repre- 

 sented by round, black dots on the swollen bodies. 



There is no limit to the advances which may be made 

 along these lines. We have probably but entered upon an 

 era which may see our methods of combating insects 

 entirely changed. 



Fig. 124. Parasitized plant 

 lice on an orange tree. 



