INSECTS IN RELATION TO MAN 397 
Introduction and Spread of Injurious Insects.— Many of 
our worst insect pests were brought accidentally from Europe, 
notably the Hessian fly, wheat midge, codling moth (prob- 
ably), gypsy moth, cabbage butterfly, cabbage aphis, clover 
leaf beetle, clover root borer, asparagus beetle, imported cur- 
rant worm and many cutworms; though few American species 
have obtained a foothold in Europe, one of the few being the 
dreaded Phylloxera, which appeared in France in 1863. 
The gypsy moth, liberated in Massachusetts in 1868, cost 
the state over one million dollars in appropriations (18g0- 
1899) and is not yet under control. The San José scale, a 
native of North China according to Marlatt, was introduced 
into the San José valley, California, about 1870, probably upon 
the flowering Chinese peach, became seriously destructive there 
in 1873, was carried across the continent to New Jersey in 
1886 or 1887 on plum stock, and thence distributed directly to 
several other states, upon nursery stock. At present the San 
José scale is a permanent menace to horticulture throughout 
the United States and is being checked or subdued only by the 
vigorous and continuous work of official entomologists, acting 
under special legislation. ‘This pernicious insect occurs also 
in Japan, Hawaii, Australia and Chile, in these places probably 
as a recent introduction. 
The Mexican cotton boll weevil (Anthonomus grandis) 
crossed the Rio Grande river and appeared in Brownsville, 
Texas, about 1892, since when it has spread over eastern Texas 
and even into western Louisiana. Advancing as it does at 
the rate of fifty miles a year, the insect would require but fif- 
teen or eighteen years to cover the entire cotton belt. The 
beetle hibernates and lays its eggs in the cotton bolls; these 
are injured both by the larva feeding within and by the beetles, 
whose feeding-punctures destroy the bolls and cause them to 
drop. If unchecked, this pest would destroy fully one half the 
cotton crop, entailing an annual loss of $250,000,000. As it 
is, the universal adoption of the cultural methods recommended 
by the Bureau of Entomology promises to reduce the damage 
to a point at which cotton can still be grown at a fair profit. 
