The only ports on the coast open to foreign trade are Salina Cruz and Puerto Angel - the first, the Pacific terminus of the Tehuantepec railway, with a spacious artificial harbour, and the second a deep but narrow natural harbour, the projected coast terminus of the Mexican Southern railway.
Allied is Sceloporus, with about 34 species, the most characteristic genus of Mexican lizards; only 4 species live in the United States, and only 3 or 4 are found south of the Isthmus of Tehuantepec and are restricted to Central America.
The Huavis inhabit four small villages among the lagoons on the southern shore of Tehuantepec and have been classed by Belmar as belonging to the Maya stock.
Indirectly the capital has a Pacific coast connexion by way of Cordoba and the F.C. Vera Cruz al Pacifico to a junction with the Tehuantepec line.
There was a narrow isthmus, formed by the sea of Verrazano, like that of Tehuantepec or Panama.