24 First Report on Economic Zoology. 



Fig. 3. — scale, false scale and effect of frost and canker. 



a, Mussel scale on apple \v(»cl ; s, the scales ; al, mussel scale eularged ; a2, its eggs ; 6, pear 

 twig showing grey scale-like spots (nomial plant structure) ; c, apple twig blisleieU 

 by frost and canker (V), not insect work ; u and c, blistered area. 



