INSECTS INJURIOUS TO CITRUS FRUITS 603 



the honey-dew of plant lice which promotes the growth of a black 

 fungus, known as the sooty-mold fungus, on the leaves and fruit, 

 and makes it necessary to wash the fruit. Washing the fruit 

 involves great loss due in part to the cost of the washing, but more 

 to the infection of the fruit with molds through abrasions in the 

 skin made in the process. The ^ 

 sooty-mold fungus on the leaves, al- 

 though it lives from the honey-dew 

 and not the leaf, interferes with the 

 growth of the leaf by forming a 

 dense coating over it. This is in- 

 jurious to the leaf and to the tree. 



The Black Scale is large, from one- 

 eight inch to one-fourth inch long, 

 more or less hemispherical in shape, 

 and somewhat wrinkled or ridged 

 on the surface. The life cycle re- 

 quires several months but eggs are 

 produced over long periods and in 

 great numbers, as many as 3000 

 from one female, so there appears to 

 be one more or less continuous gen- 

 eration. 



The Soft Brown Scale,* some- 

 times called the Turtle Back Scale 

 is similar to the one just discussed 

 but smaller, of a brown color and 

 lacking the darker markings of the U. 

 Black Scale. It is occasionally FlG> 52 7. Black Scale (Saissetia 

 locally injurious in the citrus fruit ^ &E Bern.), 



region and is present over a large part of the country, attacking 

 a variety of plants. Its injury in citrus groves is due to the honey- 

 dew and consequent growth of sooty-mold fungus. The adult 

 scales are somewhat more than one-eighth inch long and the shape 

 is less nearly hemispherical. The young are produced alive, eggs 

 being hatched within the body of the insect, and the young attack, 

 by preference, the young growth. There are three or four broods. 



* Coccus hesperidum L. 



