Final answer:
The 'feathered edge' of a blood smear is used for cell counting and morphologic evaluations, wherein cells are in a single layer and properly spread for microscopic observation.
Step-by-step explanation:
The region of a prepared blood smear that should be used to count individual cells and determine the represented morphologic features is referred to as the feathered edge. This area is characterized by a thin film of blood with single-layer spread of cells. It is achieved either manually or by machine and is subsequently stained with Wright-Giemsa stain for microscopic evaluation.
For cell counting, using a cell counter such as a hemocytometer in conjunction with a prepared slide can facilitate the tally process. It is ideal to follow a scanning pattern like the one illustrated in Figure 5, counting each white blood cell type and noting the findings in a systematic manner, possibly using a simple table for tracking.