<Ellipse Height="50" Width="100" />
<Ellipse .../> is used to draw ellipses and circles on a Canvas. The radii of an ellipse are specified using the Height and Width properties. Using equivalent Height/Width combinations will result in a circle. Figure 9-4 shows an example of an Ellipse with a longer width (x-radius) than height (y-radius).
Figure 9-4. Ellipse