18 



This species of scale is found in many of the orange growing sections, 

 where it infests lemons and oranges alike; although the individual insects 

 are easily killed, the manner in which they cling together makes it more 

 difficult. In Los Angeles, where the scale insect proved so very formidable, 

 at one time so destructive that, according to Alexander Craw, Mr. Wolf- 

 skill threatened to abandon orange growing. It does not now trouble the 

 trees much, owing to the presence of two parasites, which have nearly 

 destroyed it altogether. It is found sparingly in the foothills of the Sierra 

 Nevada, but does not seem to gain much headway. 



COTTONY GRAPE SCALE. (Figure No. 10.) 



Lecanium Vitis. 



This scale infests grapevines, and from the cottony excretions which so 

 abundantly surrounds its eggs, has been called the cottony grape scale. 

 It has more than once been confounded with the dreaded Icerya purchasi, 

 from which it is most easily distinguished, the body of the latter being soft 



Figure No. 10. 



and fleshy, while the grape scale is horny, like most all lecaniums in 

 mature state. This insect does not seem to increase, and has never been 

 very troublesome. A gentleman of San Diego has lately made the obser- 

 vation that it is attacked by a native species of ant. Probably this is the 

 check that prevents their increase. 



FILBERT SCALE. (Figure No. 11.) 



Lecanium Hemisphericum. 



The late Matthew Cooke has in his work on injurious insects a scale 

 insect called the " filbert scale," which is found on various trees, but in my 

 opinion originally spread from the live oak. So far I am not aware that it 

 has proved anything formidable; it would doubtless yield to the same 

 remedies used for the black scale. 



