PREVIOUS WORK WITH INSECT PARASITES. 31 
OTHER INTRODUCTIONS BY KOEBELE INTO CALIFORNIA. 
Mr. Koebele took a second trip to Australia, New Zealand, and the 
Fiji Islands while still an agent of the Department of Agriculture, 
but at the expense of the California State Board of Horticulture, and 
in 1893 he resigned from the United States Department of Agriculture 
and was employed by the State Board of Horticulture of California 
for still another trip to Australia and other Pacific islands. He sent 
home a large number of beneficial insects, nearly all of them, however, 
coccinellids. Several of these species were established in California, 
and are still living in different parts of the State. The overwhelming 
success of the importation of Novius cardinalis | 
was not repeated, but one of the insects 
brought over at that time, namely, the ladybird 
beetle Rhizobius ventralis Er. (fig. 5), an enemy 
of the so-called black scale (Saissetia olex Bern.), 
was colonized in various parts of California, and 
in districts where the climatic conditions proved 
favorable its work was very satisfactory, nota- 
bly in the olive plantations of Mr. Ellwood 
Cooper, near Santa Barbara. Hundreds of 
thousands of the beetles were distributed in 
California and in some localities kept the black 
scale in check. Away from the moist coast re- 
gions, however, they proved to be less effective. 
INTERNATIONAL WORK WITH ENEMIES OF THE BLACK 
SCALE. 
It will here be convenient to drop the chrono- 
logical sequence with which the subject in hand 
has been treated and to refer to the introduction Sighs 
of a very successful parasite of the black scale, “.Tivicjowus ctu 
whose work against this destructive enemy to __ blackseale: a, Adult lady- 
olive and citrus culture in California for a time Be sma ae qt; 
seemed second only to the success of the Novius : 
against the Icerya. In 1859 Motchulsky described, under the name 
Scutellista cyanea (fig. 6), a very curious little hymenopterous parasite 
reared by Nietner from the coffee scale in Ceylon. Subsequently 
this parasite became accidentally introduced into Italy and was sent 
to the senior author for identification by Dr. Antonio Berlese as a 
parasite of the wax scale, Ceroplastes rusci L. As there are wax 
scales (Ceroplastes floridensis Comst. and C. cirripediformis Comst.) 
which are more or less injurious in Florida and the Gulf States, an 
attempt was made, with Berlese’s assistance, to introduce this para- 
site at a convenient location at Baton Rouge, La., with the further 
