38 



in the figure, especially when they are crowded together; tapers towards one end, 

 and is brownish in color, though it usually resembles very closely the color of the 

 bark on which it is found, so that on light-colored bark like hawthorn it is decidedly 

 lighter in color than on the reddish-brown bark of an apple tree. 



The male scales (see No. 3, Fig. 14) as shown here, and as found in nature, are 

 like diminutive females. They are colored much the same, but are very much 

 smaller. Usually when the bark is examined they escape notice among the other 

 scales. They seem to be rare. 



It is interesting to compare Figs. 3 and 14 and see how very different in form 

 the San Jose and Oyster-shell scales are. Clearly no one need ever mistake one for 

 the other. 



Life History. — The Oyster-shell Scale, unlike the San Jose, passes the winter 

 in the egg stage beneath the scale covering. (See No. 5, Fig. 14.) The eggs are 

 glossy white, and may easily be seen if fresh-looking scales on a piece of bark are 



Fig. 15. The little white dots are the young white or 

 cream-colored larvae of the Oyster-shell scale 

 just after settling down on the bark. 



removed with a pin or knife over any black surface, ou whuh they will show up 

 clearly, as some will usually fall out during the operation. With the aid of a hand 

 lens those left inside the scale can also be seen. There are from about 20 to 100 

 eggs in each scale, and about an average of 40 or 50. In Ontario the eggs hatch 

 usually around the first of June or about the time the blossoms have fallen ; some- 

 times it is a few days later before they are all hatched, as this continues for five 

 days or more, depending apparently on the amount of heat; in hot weather 

 they hatch more quickly. The little larvae that hatch from the egg& are white or 

 cream-colored (see Fig. 15), and for a few hours after emerging they run around 

 on the bark and then settle down and insert their long, hair-like sucking tube, 

 which is just like that of the San Jose Scale (see Fig. 6), through the bark. Soon 

 they cover themselves over with a pale, brownish, waxy covering, and later, as they 

 continue to grow, the large, familiar brown scale is gradually formed. The female 

 insects never move afier they have once settled down, but remain under the brown 

 covering. The males, on the contrary, when full grown, back out from under their 

 covering as tiny two-winged little creatures (see No. 7, Fig. 14), and fertilize the 



