Cutaneous respiration
The skin of amphibians is a major site of respiration in all species for which measurements are available. Cutaneous respiration is the sole respiratory mode of lungless salamanders (family Plethodontidae) which lack lungs entirely yet constitute the largest family of salamanders. Cutaneous respiration in frogs and other amphibians may be the primary respiratory mode during colder temperatures.
Breviceps adspersus
The common rain frog lives underground, only emerging to feed and mate after a rain, usually at nighttime. Its body is stout and globular, with a flattened face. The color of this species is either light or dark brown, with rows of lighter yellow orange patches, with darker borders. It also has the short, stout limbs typical of most burrowing frogs and toads. However, its back feet are like spades and are able to dig up to 20 inches below ground. If attacked, the frog inflates and lodges itself firmly inside of the burrow. The females are also much larger than males. Since the male cannot grip the female during mating because of the size difference, the female secretes a kind of glue from her back to keep the mating pair together. The stuck-together pair burrow backwards into the soil until they reach a moist spot. Once a suitable spot is reached, the female lays her eggs. The eggs hatch directly into froglets instead of tadpoles. They are 1½ to 2¼ inches long (3 to 6 centimeters).