TRUE PARASITES. 59 
specimens being reared as late as November 10. It was subsequently 
reared many times by Mr. Alexander Craw. Mr. E. M. Ehrhorn. and 
others, in California. In the East it attacked the San Jose scale at 
the very outset, having previously existed in this part of the country 
as a parasite of other species of Diaspina?. It was reared in this 
office from material collected at Riverside. Md., and Charlottesville, 
Va.. and also from the material collected in the first orchards found 
infested, by Prof. J. B. Smith, of New Jersey. Professor Forbes has 
reared it in Illinois from the San Jose scale, and it has often been 
reared in Washington. That this insect .has been steadily on the 
increase seem> likely, but it is also probable that there is a certain 
periodicity in its increase. In Bulletin No. 57 of the Maryland Agri- 
cultural Experiment Station, published in August. 1S9S. Prof. W. G. 
Johnson stated that he did not think it possible to secure any imme- 
diate beneficial results from this parasite in the State of Maryland. 
He said that in all his efforts to secure them in his breeding cages he 
had been obliged to inclose hundreds of thousands of scales to obtain 
one parasite. Less than two years later, however.'' he stated that in a 
new locality for the San Jose scale, near Easton, Talbot County. Md.. 
he found the parasites in enormous numbers. A quantity of small 
branches incrusted with the scale were brought to his laboratory and 
inclosed in breeding tubes. Much to his surprise these tubes were 
swarming with parasites a few days later. From one tube 1.114 spec- 
imens of Aphelinus fuseipennis were taken, while a second tube gave 
132. a third 1.178, and a fourth more than 1.000. The other scale 
insects infested by this parasite are Axp}rf><Aux rapax Comst.. A*piJio- 
tus eumiymi Targ.. Lepidosaphes giotierii Pack., and Ltpklosaphes 
ulmi L. 
Aphelin us mytilaspidis Le Baron is another important parasite which. 
was reported in earlier publications as attacking the San Jose scale in 
California, where it was reared in Santa Clara County by Mr. E. M. 
Ehrhorn. It is also a common and widespread species, and infests, 
aside from the San Jose scale. Lepidosaphes ulmi, Ohionaspis pinifolim 
Fitch, and Diaspis carueli Targ. In the East it is the commonest 
parasite of the oyster-shell scale of the apple. It has only recently 
been found to attack the San Jose scale, and it is an encouraging fea- 
ture that this and other eastern species have at last found a host satis- 
factory to themselves in Aspidiotus perniciosus. It was last year 
(1905) reared at this office from San Jose scale collected at Washington, 
D. C, by Mr. A. A. Girault. and at Youngstown. X. Y.. by Mr. A. L. 
Quaintance. 
Asj_>>d>ot[pl,a<jiis citrinus Howard (fig. 7) is one of the most impor- 
tant parasites of armored scales in California, to which State it was 
evidently imported from oriental regions. In California it has been 
a Bull. No. 26, new series, Division of Entomology, U. S. Dept. of Agr., pp. 73, 74, 
