"A crystal has a center of symmetry if an imaginary line is passed from some point on its surface through…

"A crystal has a center of symmetry if an imaginary line is passed from some point on its surface through…

A design created by dividing a circle into 4 equal arcs and reflecting each arc toward the center of…

A design created by dividing a circle into 4 equal arcs and creating a reflection of each arc toward…

A design created by dividing a circle into 4 equal arcs and reflecting each arc toward the center of…

A design created by dividing a circle into 4 equal arcs and reflecting each arc toward the center of…

A design created by dividing a circle into 4 equal arcs and creating a reflection of each arc toward…

A design created by dividing a circle into 4 equal arcs and creating a reflection of each arc toward…

Illustration of an irregular convex decagon. This polygon has some symmetry.

Illustration of an irregular convex decagon. This polygon has some symmetry.

Illustration of an irregular convex decagon. This polygon has some symmetry.

Illustration of an irregular convex decagon. This polygon has some symmetry.

Illustration of an irregular convex decagon. This polygon has some symmetry.

A 6-point star made from a non-regular concave dodecagon in which all sides are equal in length. There…

Illustration of an irregular convex dodecagon. This polygon has some symmetry.

Illustration of an irregular convex dodecagon. This polygon has some symmetry.

Illustration of an irregular convex dodecagon. This polygon has some symmetry.

Illustration of an ellipse, whose major axis is vertical, inscribed in a circle whose diameter is equal…

Illustration of 16 concentric congruent ellipses that are rotated about the center at equal intervals…

Illustration of 2 concentric ellipses, whose major axes are vertical, inscribed in a circle whose diameter…

Illustration of 2 concentric congruent ellipses that are rotated about the center at 90°. The ellipses…

Illustration of 4 concentric congruent ellipses that are rotated about the center at equal intervals…

Illustration of 8 concentric congruent ellipses that are rotated about the center at equal intervals…

Illustration of concentric ellipses, whose major axes are vertical, inscribed in a circle whose diameter…

Illustration of concentric ellipses, whose major axes are vertical, inscribed in a circle whose diameter…

Illustration of 10 congruent equilateral triangles that have the same center. Each triangle has been…

Illustration of 10 congruent equilateral triangles that have the same center. Each triangle has been…

Illustration of 20 congruent equilateral triangles that have the same center. Each triangle has been…

Illustration of 5 congruent equilateral triangles that have the same center. Each triangle has been…

This is a diagram of the cross section of a fish, showing the bilateral symmetry of the parts: dv, dorsoventral…

Illustration of an irregular convex heptagon. This polygon has some symmetry.

Illustration of an irregular convex heptagon. This polygon has some symmetry.

Illustration of an irregular convex heptagon. This polygon has some symmetry.

Illustration of an irregular convex heptagon. This polygon has some symmetry.

Illustration of an irregular hexagon. This is also an example of a concave polygon with symmetry.

Illustration of an irregular hexagon. This is also an example of a concave polygon with symmetry.

Illustration of an irregular hexagon. This is also an example of a concave polygon with symmetry.

"The symmetry of the Monoclinic System is as follows: The crystallographic axis b is an axis of binary…

"The symmetry of the Normal Class of the Hexagonal System is as follows: The vertical crystallographic…

Illustration of an irregular concave octagon. This polygon has some symmetry.

Illustration of an irregular concave octagon. This polygon has some symmetry.

Illustration of an irregular concave octagon. This polygon has some symmetry.

Illustration of an irregular convex octagon. This polygon has some symmetry.

Illustration of an irregular convex octagon. This polygon has some symmetry.

Illustration of an irregular convex octagon. This polygon has some symmetry.

Illustration of an irregular convex octagon. This polygon has some symmetry.

Illustration of an irregular pentagon. This is also an example of a concave polygon with symmetry.

Illustration of an irregular pentagon. This is also an example of a convex polygon with symmetry.

Illustration of an irregular pentagon. This is also an example of a convex polygon with symmetry.

"A crystal has a center of symmetry if an imaginary line is passed from some point on its surface through…

Illustration of an irregular convex polygon with 16 sides that has symmetry. It could be used to show…

"The symmetry of the Pyritohedral class is as follows: The three crystal axes of binary symmetry; the…

"The vertical crystallographic axis is one of trigonal symmetry, and the three horizontal crystallographic…

This is a diagram of the sea-anemone, illustrating another type of radial symmetry. A, cross section;…

"The Sphenoidal Class corresponds in the Tetragonal system to the Tetrahedral class in the Isometric…