36 PARASITES OF GIPSY AND BROWN-TAIL MOTHS. 
The practical results of these importations seem to have been 
excellent. There seems to be no doubt that the parasites have been 
the controlling factor in the reduction of the leafhoppers. 
The good work in Hawaii is still continuing. Koebele is now on a 
visit to Europe to import the possible parasites of the horn fly 
(Hxmatobia serrata Rob.-Desv.), Muir is trying to find an enemy to 
a sugar-cane borer (RTiabdocnemis obscurus Boisd.), and other similar 
work is under way. 
An Importation op Clerus prom Germany. 
An early attempt to import beneficial species into the United 
States was made in 1892 by Dr. A. D. Hopkins, then entomologist 
to the West Virginia Agricultural Experiment Station and now of 
the Bureau of Entomology. A destructive barkbeetle, Dendroc- 
tonus frontalis Zimm., was extremely injurious in that State in the 
years 1889 to 1892, and Hopkins made the effort to import from 
Europe another beetle, {Clerus) Thanasimus formicarius L., from 
Germany. In Germany he collected more than a thousand specimens 
of the Clerus, which he took with him to West Virginia and distrib- 
uted in various localities infested by the barkbeetle. The following 
year, however, the barkbeetle disappeared almost completely from 
other causes, and the Clerus has not since been found. 
Marlatt's Journey for Enemies op the San Jose Scale. 
Another and later expedition was that undertaken by Mr. C. L. 
Marlatt, of the Bureau of Entomology, in search of the natural 
enemies of the San Jose scale. The question of the original home 
of the San Jose scale (Aspidiotus perniciosus Comst.) had been a 
mooted point. As is well known, it started in this country in the 
vicinity of San Jose, CaL, in the orchard of Mr. James Lick, who had 
imported trees and shrubs from many foreign countries. Mr. Lick 
died before the investigation started, and no records of his impor- 
tations were to be found. The scale was not of European origin, 
since it does not occur on the continent. In the course of investiga- 
tion it was found that it occurred in the Hawaiian Islands, in Japan, 
and in Australia, but in the case of Australia and the Hawaiian 
Islands it was shown that it had been carried on nursery stock from 
California. In 1897 plants entering the port of San Francisco from 
Japan were discovered by Mr. Craw to carry the San Jose scale. 
Correspondence, however, seemed to point to the conclusion that it 
had also been introduced into Japan from the United States. In 
1901-2 Mr. Marlatt made a trip of exploration in Japan, China, and 
other eastern countries, lasting more than a year. Six months 
were spent in Japan, and after a thorough exploration the con- 
clusion was reached that the scale is not a native of that country 
