As the surface area of most filters is less than that of a standard Petri dish, the linear range of the plate count will be less.[6] The Miles and Misra Methods or drop-plate method wherein a very small aliquot (usually about 10 microliters) of sample from each dilution in series is dropped onto a Petri dish. The drop dish must be read while the colonies are very small to prevent the loss of CFU as they grow together.[citation needed]