That's a Pacific Treefrog, HYLA REGILLA, whose treefrogness is suggested by rounded toe-pads, adhesive for climbing trees, on the somewhat camouflaged foot atop the leaf immediately below the frog's throat. Back in Mississippi we could look for about eleven members of the Treefrog Family, the Hylidae, but here the distribution maps in my field guide indicate only one species present.

Pacific Treefrogs are a varied lot, their basic skin color ranging from green to light tan to black. The black stripe through the eye seems fairly constant but the field guide says that usually there's a dark triangle between their eyes, but ours doesn't have that.

from the September 4, 2005 Newsletter, issued from the Sierra Nevada Foothills east of Sacramento, California:
PACIFIC TREEFROG IN A BOAT
Some years ago Daniel, the son of Fred & Diana and now off at pilot school, put an old rowboat next to the trailer I'm staying in now, filled it with water, rocks, cattails, pickerelweeds and fish, and made himself a boat pond. A few weeks ago both Daniel and his friend Andre were here and one day while they were exploring the old boat's ecology Diana snapped a picture of them, which I really like, so you can see the old boat, Daniel and Andre (pink cap) at http://www.backyardnature.net/ecology.htm.

Daniel and Andre moved on weeks ago but the old boat has remained, slowly leaking, being refilled every now and then and -- here's the thing -- its ecology has blossomed beautifully. Any time you can sit beside it watching mosquitofish, water striders and lots of other tiny critters. Right now the pickerelweeds bear pretty, blue flowers, and if you search among the broad, glossy pickerelweed leaves closely, usually you can find a little treefrog hunkered down waiting for the rains and a good time to call. With a very conspicuous black stripe through his eye, he's a Pacific Treefrog, HYLA REGILLA. That's him at the right.

The list of frogs and toads potentially found around Natchez, Mississippi, where I lived in recent years, bore ten treefrog species, and often identifying the treefrogs I ran across was a real challenge. Here treefrog identification is a cinch because there's only one member of the Treefrog Family, and that's the Pacific Treefrog.