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Show 206 DR. H. GADOW ON MEXICAN [June 6, Isthmus, B. coccifer and B. sternosignatus; or they extend into the Atlantic hot-lands, canaliferus; or along the Western Sierra Madre into Jalisco, intermedins, with marmoreus peculiar to South-western Mexico; or they go as typical hot-country Toads into both the eastern and western Tierra Caliente, marinus, valliceps on the Atlantic side from Nicaragua to Texas, not on the plateau, but recorded from Jalisco and Presidio near Mazatlan; lastly, B. simus from Panama on to and over most of the Mexican plateau. 3. Northerners, chiefly at home in the South-western United States and in the northern half of Mexico, eventuallly extending south over the Central plateau : B. punctatus, debilis, compactiUs. Of the Bufonidse which are found in the Greater Antilles all are now separate, insular species, except B. marinus, which has probably been introduced. H y l i d .e .-- The creative centre of this family is decidedly South America. Every one of the 14 genera of Hylidee is found in America, and it is only by the large genus Hyla (incl. the slightly modified Hylella) that this family has attained its world-wide range with the remarkable exception of the whole Pakeo-tropical region. From North-western South America they have spread through Central America into the Antilles (about 7 or 8 species, mostly peculiar), and through Mexico into North America. Concerning Mexico they fall into the following groups :- 1. Genera peculiar to Mexico: Pternohyla, P. fodiens of Presidio near Mazatlan ; Triprion, T. petasatus of Yucatan ; but Diaglena jordani of Ecuador and Corythomantis greeningi of Brazil point to the south as the old centre of these peculiar Mexicans. 2. Genera with preponderating numbers of species in Central and South America, while comparatively few have reached, or have been developed in, Mexico : Phyllomedusa with only P. dacnicolor on the Pacific side, Agalychnis callidryas and Nototrema oviferum in the Atlantic Tierra Caliente. P . dacnicolor is saturated green, often with the same white temporary patches or spots as happen so frequently in the Australian Ilyla c air idea. They were pairing at Rio Balsas in the month of June. During the nightly thunderstorms the males kept up an incessant noise like the snarling bark of little dogs, llie couples were sitting in low shrubs or amongst herbs, a foot above the ground, overhanging little ditches which led into a dirty stagnant pool. During the daytime the ditches were absolutely dry. lh e eggs are very small, very numerous, and of a light grass-green colour. 3. Hyla. About 15 species are recorded from Mexico, to which no less than 11 seem to be peculiar, but at least 8 of these have hitherto been found in single localities only. Our knowledge of the distribution of Tree-frogs is still very defective. Most of them inhabit the forest-regions of the Atlantic slope. They are dis |