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Nebraska State Horticultural Society. 



in color, indicated the presence of the parasitic egg or larva. It is this 

 species probably- more than any other which is responsible for the 

 fluctuations in numbers of the cottony scale." 



Dr. Howard also further says that it is probably only through the 

 influence of a damp and rainy season, which prevents these aclive little 

 parasites from flying about to any extent, that the scale is able to over- 

 come the effects of its attacks, enormously prolific as the Puhanaria 

 is. Other parasites of somewhat less importance but which aid very 

 materially in the destruction of the scale areCoccophagus flavoscut- 

 elliim, a more southern species than the one referred to above, 

 Atropates collinsi, Eiinotus lividus, Aphycus pulvinariae and Comys 

 fiisca. 



The pretty little insects known as the lady birds play an ex- 

 tremely important role in checking the advance of the scale by prey- 

 ing upon them in their early stages, including the egg. Perhaps the 

 most important of these is the twice-stabbed lady bird, Chilocorus 

 bivuluerus, a small black insect with two red dots. Another one of 

 similar appearance is Hyperaspis binotata. .H. Siffiiata has also beea 

 found to prey on the scale, and here at Lincoln, H. proba has been 

 reared from that insect. Mr. J. G. Sanders found in the severely in- 

 fested parks and cemeteries of Chicago that the egg-contents of 

 80 to 85 per cent of the cottony ovisacs had been destroyed by the 

 larvae of Hyperaspis. 



Hyperaspis proba; an Important Enemy of the Cottony Maple Scale. 



