Alligators are found in the low coast region and are especially numerous in the Nueces river.
In Central and South America alligators are represented by five species of the genus Caiman, which differs from Alligator by the absence of a bony septum between the nostrils, and the ventral armour is composed of overlapping bony scutes, each of which is formed of two parts united by a suture.
Alligators and crocodiles are numerous in the lagoons and rivers of the coast and the iguana is to be found everywhere throughout the tropical lowlands, the large black Ctenosura acanthinurus being partly arboreal in habit when full grown.
Other species, especially the alligators, make a very large nest of leaves, twigs and humus, scraping together a mound about a yard high and two or more yards in diameter.
Hippopotami are found on the coast, and alligators are common in the rivers and lagoons of the low country.