INSECTS INJURIOUS TO CITRUS GROVES. 595 



margin, which is notched on the sides and behind; this 

 shape, with the brownish color, gives it its popular name. 

 The legs are concealed beneath the body. 



The young insect is of a yellowish color, and always 

 settles upon the bark and leaves of tender growth. The 

 adult insects appear to be unable to pierce the bark of 

 the trunk or older branches, always being found upon 

 wood of newest growth. 



In the spring and early summer, when new growth 

 is forming, the increase of the insect is most rapid, es- 

 pecially during the month of June. Later in the season 

 the colonies disappear, only a few gravid females re- 

 maining to restock the plants at the next favorable op- 

 portunity. The young, hatching in the latter part of the 

 season, often starve, because they are unable to reach 

 tender twigs upon which to feed. 



Treatment. Solutions Nos. (9), (8), (7) or (6). 



The Black Scale, (Lecanium olece Bernard.) This scale 

 is nearly black in color, approaching hemispherical in form, 

 and longer than broad. Length from 0.16 to 0.20 of an inch 

 (4 to 5mm.), height about 0.12 of an inch (3 mm.). The 

 middle of the back carries an elevated keel, which is 

 crossed at right angles by two elevated ridges, the latter 

 dividing the body into three nearly equal parts. The 

 body is slightly margined, the outer part of the disk 

 being marked with many small ridges, which extend from 

 the margin half way up to the centre of the back. 



The eggs are long, oval in shape, about .0012 of an 

 inch in length and of a yellowish color. 



The young larvae prefer the smaller twigs of the 

 plants which they infest, and usually settle upon the 

 leaves. The development of the species is slow, so there 

 is probably not more than one brood per year. It lives 



