4 BULLETIN 1223, U. S. DEPARTMENT OF AGRICULTURE. 
of Salt Lake City and in the region between these two extremes, 
where it occasionally does severe damage. In Nevada it is confined 
to a limited area in the west-central part of the State, extending 
from Carson City to Reno, according to S. B. Doten (3, 5), director 
of the Nevada Agricultural Experiment Station, and from the 
writer’s personal observations. A. L. Melander (/6), entomologist 
of the Washington Agricultural Experiment Station, reports that 
he has not found it anywhere in the State of Washington, except 
at Spokane, where it has been for 15 years or more. The files of 
the Bureau of Entomology also contain records of this insect oc- 
curring at Coeur d’ Alene and Boise, Idaho. 
In California, the insect is somewhat more widespread, occuring 
in a number of localities in the northern and central portions of 
the State. It has been found in or near the following towns: Ukiah, 
San Rafael, Colusa, 
Woodland, Davis, 
Sacramento, Stock- 
ton, Modesto, Oak- 
dale, Woodside, 
Redwood City, Palo 
Alto, Stanford Uni- 
versity, Mayfield, 
Mountain View, Los 
Altos, Santa Clara, 
College Park, San 
Jose, Milpitas, Eden- 
vale, Los Gatos, and 
Saratoga. 
Additional locali- 
ties in the United 
States and Canada 
have been recorded 
by Albert Hart- 
zell (8). 
SPREAD. 
The elm scale was 
Ite. 1.—Known distribution of European elm scale in the 
West. in all probability 
brought to America 
from Europe on young elm trees. The shipment of elm stock from 
infested nurseries to various parts of the United States has also been 
the cause of its being scattered over such a wide territory. 
In these infested localities the scale has spread from tree to tree 
by several agencies. Birds, such as English sparrows, which are 
to be found in large numbers in the shade trees of almost any town, 
probably carry the young crawling scales for considerable distances 
on their feet. During the fall infested leaves drop to the ground 
and are blown for some distance by the wind. A certain percentage 
of these larve happen to find themselves at the base of an elm tree 
and crawl up to start a new infestation. The European elm scale 
has been seen spreading in this manner by both Professor Doten 
and the writer, The Argentine (/ridomyrmex humilis Mayr) and 
