A method and apparatus for identifying one or more target constituents (e.g., white blood cells) within a biological sample is provided. The method includes the steps of: a) adding at least one colorant to the sample; b) disposing the sample into a chamber defined by at least one transparent panel; c) creating at least one image of the sample quiescently residing within the chamber; d) identifying target constituents within the sample image; e) quantitatively analyzing at least some of the identified target constituents within the image relative to one or more predetermined quantitatively determinable features; and f) identifying at least one type of target constituent within the identified target constituents using the quantitatively determinable features.