2Q The San Jose Scale iti Japan. 



XI. Two Natural Enemies of the sc^a^e. 



The two most effective natural enemies of the scale in Ja{:an are the so 

 called Asiatic ladybird (Chilocorus similis) and a parasitic fungus 

 (SPHJiROSTiLBE coccophila) ; a detailed account of these can not now be 

 given here, for they are still under observation, bat we shall simply men- 

 tion some facts related to them. 



AVe find the ladybird feeding on Diaspis pentagona more coujmonly 

 than on the scale, and it seems to choose the former rather than the latter, it 

 is, however, more or less a general feeder, and feeds upon D. pentagona and 

 the scale as well as other small insects. It freely feeds upon the common 

 aphis, but does not readily attack the wooly aphis ; very often we have seen 

 the cast skins of pupae as many as a dozen or more in a group on a branch 

 of a tree, where were plenty of D. pentagona, while it is very seldom to 

 find even a few of the cast skins in a group with the scale colony. When 

 the writer visited Mr. 3v. Abe's pear orchard near Kokura in the Summer 

 1900, he found a great modification of the scale ; but when he visited the 

 same orchard last year again, he found that the insects were so generally 

 attacked by the fungus Sph.erostilbe coccophila, that live females had 

 seldom been seen. Mr. H. Nomura said in his article * on the fungus that 

 71 out of 73 of the scale were dead from the effect of the fungu.s. 



The fungus attacks Diaspis pentagona as well as the scale ; indeed the 

 writer believes that the disease exists on D. pentagona as the principal host, 

 although it attacks other scales, as the San Jose Scale and Parlatoria. The 

 fungus is widely spread among D. pentagona in the country even in very 

 high regions as Mt. Togakushi, Shinano province ; the fungus does not 

 reach, however, the San Jose Scale in many localities, but is spreading 

 gradually. 



* Bui. No. 18, Imperial agricultural exp. station in Japan, 1901. 



