Since publication of the author's initial bibliography of the alfalfa weevil (Cothran 1966), the insect has continued to spread (see Table 1) and has now been reported from all of the conterminous United States except Florida and Minnesota. It was also collected for the first time in Ontario in 1967 (MacLachlan 1967) adding eastern Canada to its New World range. Commensurate with this spread has been a continuing increase in its economic importance. A recent estimate of the annual losses caused by the weevil in the states where it has attained economic levels exceeds 56,000,000 (USDA 1967b). It has been the most important single pest of alfalfa in the U. S. since 1963 (USDA 1964, 1967a, 1968a) and is now considered to be the major agricultural pest in Wyoming, Pennsylvania, New Jersey and Montana (USDA 1963, 1966a, 1967b, 1968a). It has been responsible for a reduction in alfalfa acreage in many states and has caused especially severe curtailment of the crop in several southern states. In Tennessee alfalfa acreage has declined from 147,000 acres in 1964 to 100,000 in 1966 (USDA 1967b), in Georgia from 45,000 in 1958 to 10,000 in 1965 (USDA 1965), and in Alabama from 200,000 to 2,000 during the period 1959–1966 (USDA 1967b).