| OCR Text |
Show 1 9 0 5 .] AMPHIBIANS AND REPTILES. 2 0 9 C r o c o d il ia . Crocodilus americanus is the commonest tropical American Crocodile, from Florida to Northern South America. In Mexico it is strictly confined to the Tierra Caliente, with Mazatlan as its north-western limit. It ascends the Rio Balsas at least up to Mescala, but this is not much more than 1700 feet above sea-level. Common in the lagoons on the coast of Guerrero and Oaxaca, except where it has recently been well-nigh exterminated by American skin-hunters. More exist in the river-systems of the State of Vera Cruz, ascending occasionally up to Motzorongo, i. e. 1500 feet. During the rainy season they often forsake the then turbid rivers, and roam at night through the forests in search of lagoons. C. moreleti inhabits the Tierra Caliente from Tampico to Honduras. Caiman sclerops s. punctulatus has its centre in South America. In America it occurs only in the Atlantic hot-lands. I met with very large specimens (length of skull 20 inches) at Agua fria in the same lagoons and rivers as the Crocodile. Whilst the latter, anyhow not averse to brackish water, inhabits the Greater Antilles, the Caiman has found its way only into Trinidad and, if report is true, to Martinique. The Alligator of the southern United States does not seem to cross the Rio Grande. C h e l o n i a . It seems almost incredible that Chelydra has never been recorded from Mexico, considering the wide range of Ch. serpentina in the United States and the existence of the other species, Ch. rossignoni, from Guatemala to Ecuador. The Papaloapan and S. Juan Rivers of the State of Vera Cruz are certainly large enough, with pools and backwaters, but I could not ascertain the presence of a large, snappy species. D e r m a t e m y d id j E.- The few species of this family are peculiar to Central America. Dermatemys mawi extends from Honduras into Yucatan and Vera Cruz; it occurs, for instance, in the pools of the forests and savannahs near Tetela, where it is known as the " Tortuga blanca." Staurotypus seems to have a similar range : S. triporcatus going up to Vera Cruz; S. biporcatus only up to the Isthmus. C in o s t e r n id ^e , with the sole genus Cinosternum. About 10 species in North and Central America, one extending to Guiana. Well represented in Mexico by 6 species. Of these, C. pennsyl-vanicum, previously recorded from the Valley of Mexico, was found by myself in South Guerrero, at San Luis Allende. C. hirtipes ranges from Arizona and New Mexico along the Pacific side into Jalisco, and includes the Ti'es Marias Islands. P roc . Z ool. S oc.-1905, V o l . II. No. XIV. 14 |
