Bullfrog and Green Frog

Here is a good shot of a Bullfrog sitting on a rock in the large pond. The feature that distinguishes the Bullfrog from the Green Frog is the line around the circle behind his eye. On the Bullfrog, the line follows the circle down. On the Green Frog the line continues straight toward the back of the frog.
The second picture shows a Green Frog sitting on a bucket hiding behind a Sweet Flag leaf. I wonder if he thinks I can't see him. If you look close, you can see the line continues straight down his back.