--- a/gfx/2d/2D.h
+++ b/gfx/2d/2D.h
@@ -241,18 +241,20 @@ public:
  * This class is used for Radial Gradient Patterns, the gradient stops are
  * stored in a separate object and are backend dependent. This class itself
  * may be used on the stack.
  */
 class RadialGradientPattern : public Pattern
 {
 public:
   /*
-   * aBegin Start of the linear gradient
-   * aEnd End of the linear gradient
+   * aCenter1 Center of the inner (focal) circle.
+   * aCenter2 Center of the outer circle.
+   * aRadius1 Radius of the inner (focal) circle.
+   * aRadius2 Radius of the outer circle.
    * aStops GradientStops object for this gradient, this should match the
    *        backend type of the draw target this pattern will be used with.
    * aMatrix A matrix that transforms the pattern into user space
    */
   RadialGradientPattern(const Point &aCenter1,
                         const Point &aCenter2,
                         Float aRadius1,
                         Float aRadius2,