HISTORY AND DISTRIBUTION. 15 
occupied territory, as illustrated by the infestation at New Orleans, 
to areas where the ants are so scarce that one not accustomed to their 
habits would fail to discover them. The latter condition prevails at 
present in Mobile, Ala. The only places remote from railroads 
where they have been discovered are upon the banks of the Missis- 
sippi River below infested localities. Their presence in such loca- 
tions is easily accounted for by supposing that they have been carried 
thither on driftwood, which, carrying numbers of ants from infested 
places farther up the stream, has become stranded on the river banks, 
thus establishing new foci. In all other cases the infested territory 
is on a railroad, and usually on a main line running out from New 
Orleans. For example, nearly every town along the Southern Pa- 
cific Railway between New Orleans and Lake Charles is infested, and 
the same statement applies to points on the Louisville & Nashville 
Railroad between New Orleans and Mobile. 
OCCURRENCE AND DISTRIBUTION IN CALIFORNIA. 
The first specimens of the Argentine ant observed in California 
were collected in 1907 by Mr. J. Chester Bradley, at that time an 
assistant in the entomological department of the University of Cal- 
ifornia. The identity of the specimens was not established until 
1908, when Dr. W. M. Wheeler found them to be Iridomyrmex Jiumilis 
Mayr. 
As soon as the dangerous nature of the pest was known, Prof. C. W. 
Woodworth took steps to make a study of the species along the same 
lines as was being conducted in Louisiana at that time, and as a result 
of his preliminary work he issued a warning circular x to the public 
in August, 1908. In this circular he gave a brief outline of the 
habits of the ant and reported the following localities as infested: 
In the central portion of the State, East Oakland, Alameda, San 
Francisco, San Jose, Cupertino, and a point near Campbell; in the 
southern part of the State, Los Angeles, Azusa, and Upland. 
In 1910 Prof. Woodworth published another small bulletin 2 giving 
the results of his two years' study of the insect. In this paper the 
infested territory was more clearly defined, and was estimated as 
consisting of a total area of 5,000 acres. About twice the area was 
reported infested in 1910 as in 1908, owing to the discovery of a few 
new colonies and the natural spread of the ones first discovered. 
Our information as to the extent of the infested area in California 
(see fig. 2) has been obtained principally through the kind offices of 
Mr. Ralph Benton, of the California Agricultural Experiment Station, 
and Mr. P. E. Smith, of Santa Paula, CaL, as well as from the publi- 
i The Argentine ant in California. Cal. Exp. Sta. Cir. 38, Berkeley, Cal., August, 1908. 
2 The control of the Argentine ant. Cal. Exp. Sta. Bui. 207, Berkeley, Cal., October, 1910. 
