No. 4.] 8CALK IXSI^XTS. 429 



Upon linding a satistUctoiy pltico on which to locate, the 

 young insect inserts its beak in the phmt and begins to suck 

 its juices ; while fine, wax\ threads ap})ear on the surfiice of 

 the body, and soon unite to form the coverini;: scale. This 

 is circular in outline, white in color and highest in the middle. 

 About ten days later the insect moults, and adds its moulted 

 skin to this scale, which has now become darker, giving the 

 entire scale thus formed a gray color, with a yellowish or 

 whitish centre. Shorth' after this tlu^ female insects moult 

 aiiain, addint>- the moulted skin to the scale, as before, and 



~ ' ~ 7 7 



no\v soon become adult. 



Distrlhntlon. 



If, while the young scale insects are crawling about, a 

 bird lights on the tree, it is not unusual for one or more of 

 them to crawl on to its feet, and thus be carried some dis- 

 tance when it flies, before they can crawl off again at the 

 bird's next resting place, thus establishing them in some 

 other portion of the town or city. The larger insects, also, 

 aid in scattering these insects in this way, while sudden 

 gusts of Avind may carry the \ oung from tree to tree in an 

 orchard. 



The most usual method of distribution is by means of 

 nursery stock infested with this pest, each infested plant sent 

 out becoming a centre from which this insect spreads in all 

 directions. 



Enemie.'i. 



The chief foes of the San Jose scale are the ladj^-bugs or 

 lady-birds. These are small beetles, nearly circular in out- 

 line and very convex. One of the most important of these 

 is the "Twice-stabbed lady-bug," which is about an eighth 

 of an inch long, shining black, with a small red spot on 

 each side. A much smaller black beetle, known as Pentilia 

 miseJIa, also feeds upon the scale. 



Recently a lady-bug very similar to the "Twice-stabbed 

 lady-bug" has been found in China, destroying the San 

 Jose scale there ; and colonies of this insect have been 

 brought to this country hy the United States Department of 

 Agriculture, in the hope that it may be of t'qual value here. 



