A very fine textured Ajuga with deep purple foliage.  The leaves on this plant are about a 1/2" wide and an inch or two long.  This variety doesn't spread as quickly as other varieties but over time will form an excellent mat of foliage to cover the ground.  In spring it pushes up blue/purple spikes of flower.  A great planting of this can be found in the Pavilion Garden at Yew Dell.