We describe a simple silicone membrane for in vitro feeding of Ixodes scapularis (Say), the main tick vector of Lyme borreliosis in the United States. Membranes are prepared using regenerated cellulose lens paper, which is coated with a controlled layer of silicone by submerging and removing the paper in a defined solution of silicone glue dissolved in toluene. Median engorged weight obtained by I. scapularis fed on defibrinated bovine blood using these membranes was 109 mg (32-198 mg). These ticks laid eggs in the laboratory and larvae hatched 6 wk later. This method simplifies artificial membranes for in vitro feeding of ixodid ticks, which have long required a considerable amount of skill and experience to prepare.