426 OHIO EXPERIMENT STATION: BULLETIN 332 



PLATE XLVIII 



Fig. 1. The Oyster Shell Bark Louse (Lepidosaphes ulmi). Mature female 

 scales, enlarged. 



Fig. 2. The Willow Scurfy Scale (Chionaspis salicis-nigrae) . Mature 

 female scales, enlarged. 



Fig. 3. The Scurfy Bark Louse (Chionaspis fur fur a). Male scales on twig 

 at left, female scales on twig at right. Enlarged. 



