SCALE INSECTS. 25 



mens, but darker when dried. The exuviae are usually 

 slightly to one side of the center and covered with excre- 

 tion ; the nipple-like prominence in rubbed specimens is 

 reddish or yellowish brown, surrounded by a band a little 

 darker than the margin. Scale rather convex, delicate, and 

 easily torn when removed from fresh material. It varies 

 considerably in size, the average diameter being about 



Scale of Male. The scale of the male is elongate oval, 

 and is darker and not so delicate as the scale of the female. 

 Nipple-like prominence situated between the center and 

 the anterior margin, usually covered with excretion, and, 

 when rubbed or broken, of about the same color as that of 

 the female scale. Margins thin and delicate, and lighter 

 than the rest of the scale. Length about 1 mm. (.04 inch) ; 

 width about 3""" (yj^o inch).' 



Remedies. Same as those used asrainst San Jose scale. 



THE OYSTER'SHELL BARK-LOUSE. 



[MytUaspis pomo7-u7n Boucbe.) 



This insect is cosmopolitan. It is found in all parts of the 

 United States and probably came originally from Europe. 

 It has been reported in Kansas from Douglas, Crawford and 

 Lyon counties, and doubtless exists elsewhere in the state. 



Food Plants. Apple, pear, quince, hawthorn, buck- 

 thorn, raspberry, currant, linden, hop-tree, bladder nut, 

 horse chestnut, maple, water locust, honeysuckle, ash, elm, 

 hackberry, cottonwood, willow, poplar. 



Life-history.*^ The female dies during the early part 

 of winter, leaving a number of eggs, ranging from 42 to 86. 

 If the shell is broken open in winter months these eggs are 

 easily seen with the naked eye. These hatch the latter part 

 of May and seek permanent positions upon tips of twigs. 

 The species is single brooded in the North. After insert- 

 ing beak in plant, the female molts twice, then produces 

 that long scale covering resembling somewhat a minute 

 oyster shell, from which the name arises. 



^Bul. 111. State Lab., Vol. IV, Art. XIII. 

 8 From Year-book U. S. Dept. Agr., 1894. 



