REPORT OF THE ENTOMOLOGIST. 469 



subsequent and independent imj)ortations, but that this is the one 

 from which the main spread originated there can be little doubt. 



ITS SPREAD AND PRESENT LIMITATION IN CALIFORNIA. 



We are indebted to Mr. Matthew Cooke, of Sacramento, for com- 

 municating a lengthy and careful account of the localities in which 

 the pest at present exists in California. Mr. Cooke has mapped out 

 ten districts, six in the counties of Marin, San Mateo, Santa Clara, 

 Sacramento, Sonoma, and Napa, in the San Francisco region, and four 

 in the counties of Santa Barbara and Los Angeles, in the southern por- 

 tion of the State. 



The first infested district extends from Menlo Park to San Mateo, 

 a distance of 10 miles. It is bounded on the east by the Southern 

 Pacific Railroad, and extends some 3 miles west, including in conse- 

 quence some 30 square miles. But little effort, according to Mr. 

 Cooke, has been made to eradicate the pest in this district. 



The second infested district is contained within the town limits of 

 San Rafael, Marin County, about 14 miles north of San Francisco. 

 In this district it has been held in check, but there are still some to 

 be found, and its increase is only dependent upon a lapse of vigilance. 



The third infested district includes the city of San Jos^ and the 

 town of Santa Clara, and contains an area of about 16 square miles. 

 In these towns the scale insects infested the ornamental and shade 

 trees and shrubbery, but did not seem to trouble the deciduous fruit 

 trees to any extent. At San Josd energetic measures have been taken; 

 the trees have been cut back and their trunks scrubbed until the pest 

 has been thoroughly eradicated. At Santa Clara, however, little has 

 been done, and some places are seriously infested. 



The fourth infested district occurs at the city of Sacramento, where 

 only-about 120 acres are infested, although it is stated to be rapidly 

 spreading. The insect was first discovered in this district by Mr. 

 Cooke in October, 1885, in about eight gardens. The city trustees 

 appropriated $200, and with this sum it was destroyed, except upon 

 certain premises which the authorities could not enter. Mr. Cooke 

 gives in this connection, as an instance of the rapidity of the multi- 

 plication and sx3read of the insect, the following: 



In October, 1885, a patch of these insects covered a space of about 3 by 4 inches 

 was noticed upon a limb of an Acacia tree. Fi-om these it spread, and in a little 

 more than a year several Orange and Lemon trees and other plants growing closely 

 in an area of about 160 by 80 feet had become seriously infested. 



The fifth infested district is found at Healdsburg, Sonoma County, 

 about 65 miles north by west of San Francisco. Here the insect 'is 

 mainly comprised within the town limits, and infests the shade trees 

 along the streets and the shrubbery in the gardens. 



In Mr. Cooke's sixth district the insect cannot be said to exist at 

 present. It comprises a single garden in the town of Saint Helena, 

 Napa County, about GO miles north by east of San Francisco. It 

 was found upon a rose bush in that place by Mrs. Richard Wood in 

 October, 1882. The bush was destroyed, and the pest has not been 

 found in that section since. 



The seventh infested district includes the city of Los Angeles, where 

 the insect is principally confined, according to Mr. Cooke, to the gar- 

 dens and suburbs on the eastern side of the city. Mr. Coquillett says 

 that as nearly as can be ascertained the insect was first introduced 



