Davis 942 Pava Eslope Fox Esesimiles, 7300', Dept Chalatenango, El Salvador March 20, 1942. bottom over some dead leaves. The dark greenish-brown Dorsum afforded excellent protection concealment against this background. Sturton chased the frog through the silt and finally caught it. However, we had seen a smaller, paler individual in the same pool, so kept after it. Sturton finally chased it out of the silt and it headed toward me. At the same time a third indi- vidual, large & dark like the first, came to the surface. Sturton caught it. The small frog hopped out onto the bank in an effort to get past me, I caught it, while sit- ting on the rocky bank waiting for Sturton to button his shoes, a large dark frog of the same species jum- ped out of the grass and landed next some, I caught it. This is the weirdest, fastest moving free species of frog I have ever tried to catch. All 4 individuals are F's. We heard no frogs in voice all afternoon, although I had heard 5 calling in the a.m. without locating a single one. Inasmuch as Sturton had seen two frogs dive into this same pool yesterday afternoon, it would seem that individuals stay close to the same pool. Coloration: 3 individuals (1405-7) are large & dark. At the time of collection the chin & throat was dark rusty brown, but an hour later, though still alive, chin & throat were a dirty white. Dorsum marbled dark olive-brown & pea- green, former color predominating. Silvery-white line