10 



the resulting grubs consuming the body substance of their host in 

 the course of their growth. The abundance of these small parasites 

 varies greatly with the locality and the time of year. Dr. L. O. 

 Howard," who has given much attention to the parasites of the San 

 Jose and other scales, records for this species the following: ApTieli- 

 nus fuscipennis How., Aphelinus mytilaspidis Le B., AspidiotipJia- 

 gus citrinus How., Anaphes gracilis How., PJiyscus varicornis How., 

 Prospalta aurantii How., Ahlerus clisiocampse Ashm., and RJiopoideus 

 citrinus How. 



-^^. 



Fig. 6. — The Asiatic ladybird ( Chilocorus similis), almost identical with the twice-stabbed ladybird ( C. 

 bivulnerus), predatory on the San Jose scale: a, Second-stage larva; 6, cast skin of same; c, full-grown 

 larva; d, method of pupation, the pupa being retained in split larval skin; e, newly emerged adult not 

 yet colored; /, fully colored and perfect adult. All enlarged to the same scale. (From Marlatt. ) 



Parasitism by these insects is indicated by a small round hole in 

 the scale covering of the insect, through which the adult parasite 

 has made its escape. Any orchardist, however, may satisfy him- 

 self as to the presence of these little friends by inclosing in a glass 

 vial a badly infested twig, for in the course of a few days the minute 

 flies, if present, will begin to emerge. 



Considerable attention has been given to the subject of fungous dis- 

 eases of the San Jose scale, and numerous attempts conducted in a 

 thoroughly scientific manner, notably by Prof. P. H. Rolfs, director 

 of the Florida Agricultural Experiment Station, have been made to 



a Bul. 62, Bureau of Entomology, U. S. Dept. of Agriculture, pp. 58-62, 1906. 

 [Cir. 124] 



