Green frogs have well-defined back ridges.
Bull frogs are sort of squodgy, ill-defined, squishy-looking lumps. With legs. (Okay, their noses are cute enough to consider kissing.) Amazing that I was able to get a photo of this little one at all; I certainly wasn't expecting anything close to focused. It usually screams and leaps for cover when it sees me coming. (Seriously, it lets out this high-pitched Eek! and dives for the water practically before I've even had a chance to notice it. This is the best view I've had of it yet.)
The green frogs, however, are fearless. And really damn cute, standing sentinel over The Puddle.
