FIELD BOOK OF INSECTS. 



competent to identify the trouble. Cutting into the 

 bark under a San Jose scale is almost sure to reveal a 

 reddish discoloration of the green tissues beneath. . . . 

 The winter is passed by this insect in a partly grown, 

 dormant condition. Vital activities are resumed with the 

 approach of warm weather, and the first outward indications 

 of life are seen in the appearance of winged males and later 

 of the crawling young, the latter of which appear in this 

 latitude [New York] toward the last of June. . . . The 

 females continue to produce young for a period of about 

 six weeks, each averaging about 400, or from nine to 10 

 every 24 hours. This is an ovo-viviparous species. That 

 is, the eggs develop within the mother and the young are 

 born alive. They may be seen as tiny yellow specks escap- 

 ing from under the maternal scale, from which they wander 

 in search of a favorable place to establish themselves. 

 . . . The development of the scale begins, even before 

 the young has selected its feeding place, as very minute, 

 white, waxy filaments, which spring from all parts of the 

 body, rapidly become thicker, and slowly mat down to 

 form the circular white scale with a depressed ring and 

 central elevation. . . . Thus the round of life may be com- 

 pleted, as determined from a study of the female, in from 

 33 to 40 days. The detailed studies made at Washington 

 show that four full generations are developed normally 

 in that latitude and that there may be a partial fifth." 

 The fact that this insect lives on a great variety of woody 

 plants makes eradication difficult; we must spray more 

 than the few trees we care about. If you have it, notify 

 your State Entomologist and do not trust to Jim Jones 

 around the corner, who says he can kill it for you. It is a 

 native of eastern Asia; San Jose, California, is connected 

 with it merely because the specimens upon which the 

 first scientific description was based came from there. 



Lepidosaphes ulmi, called Mytilaspis pomorum in many 

 publications, is the Oyster-shell Scale. It infests a variety 

 of trees, including apple, and is well described by its com- 

 mon name, although the oyster-shell shape is not entirely 

 diagnostic. The small end of the tapering, slightly curved 

 scale is usually yellowish. See Plate XXIV for it and 

 other species. 



94 



