21. Law enforcement always looks at providing three concentric rings of security for big events, 22. Concentric ring fractures formed around the volcano, creating convenient conduits for additional volcanic vents.23. The thrower stands at the centre of concentric rings marked on an open field. 24. In butterflies, the spots are composed of concentric rings of scales in different colors. 25. Eight concentric rings are inscribed on the compass rose. 26. This genus is characterized especially by the concentric rings of muscle fibers in the proboscis. 27. The spicules form blade-like structures, ornamented with concentric rings . 28. The Mexican government has designated concentric rings around the ruins as having certain archeological values. 29. Other stucco designs that can be seen in Gubyaukgyi include concentric rings and ogre figurines. 30. These disks were concentric rings of fonts on a transparent plastic material in negative form.
