This may be an active flowing of more blood than common through a part, or a passive collection of blood in the part. Stimulation produces the former; when it passes beyond the line of health into irritation, passive congestion occurs at the centre of the irritation, active congestion in the parts around it. Determination of blood towards any portion of the body may be, when very decided, called local hyperaemia. A bloodless condition of an organ is called a local anosmia. This first simply means excess of blood ; the second, deficiency of blood.