1905.] AMPHIBIANS AND REPTILES. 207 



covered and caught by mere accident. For instance, I found one 

 single specimen of H. staufferi at Motzorongo, a species until then 

 known only from Guatemala. H, boucourti of the same country 

 has been recorded once from Tepic, none from the enormous 

 intervening stretch. II. miotympammi seems to range from the 

 Isthmus through the mountainous parts of Vera Cruz, going up 

 towards Puebla. H. venulosa is an eastern form, from South 

 America to Tampico, decidedly Atlantic, but once recorded from 

 near Mazatlan. H, baudini, the commonest Tree-frog, ranges from 

 Ecuador right through Central America, and then spreads east and 

 west through the hot countries of Mexico, absolutely avoiding the 

 plateau, but reaching Texas. 



On July 4, 1902, when the rains were very irregular, we found 

 II. baudini spawning, south of Coixioba, On a piece of inundated 

 woodland meadoAv, about the size of a suburban lawn, were 45,000 

 frogs at a low comj)utation, two-thirds of them in amplexus, the 

 other males making a deafening din. ISText day the pool was dried 

 up completely, the grass glazed with the spawn, and there was not 

 a single frog to be heard or seen in the neighbourhood. 



H. cojjei, known as " Sapo bianco" or white toad, is a hill form. 

 Known already from Texas, Chihuahua, Guanajuato, and Jalisco, 

 I found it plentiful on the whitish calcareous terrain south of 

 Chilpancingo, not in the ti'ees but sometimes on rather barren 

 and dry fields. Decidedly typical of the western and southern 

 plateau and its Pacific slope, and very abundant, is II. eximia. 



Residt. — Mexico has many Hylidse in common with Central and 

 even South America ; but the majority are now peculiar to Mexico, 

 and only two, H. copei and H. bcmdini, extend northwards into 

 Texas. 



CYSTiGNATHiDyE, like tlie Hylidoe, of decidedly South- American 

 origin. Of the 15 or 16 genera of this family only Lejotodactyhis *, 

 Paludicola, 6'7/rrhopus, Ilylodes *, and Borborocvetes occur also in 

 Mexico, altogether with some 23 species. Those marked * are also 

 Antillean. Not one reaches the United States ; in fact the most 

 northern record is made by II. calcitrans at Zacatecas. B. mexi- 

 canus is peculiar to the Central plateau and the high mountains of 

 Jalisco, Oolima, and Guerrero. Of the 9 or 10 species of Ilylodes 

 6 are restricted to Mexico, but their recorded localities are still 

 too few and scattered. The same applies to the six species of 

 Syrrhopus ; the others range far south to Nicaragua and Costa 

 Rica : H. pahnalus is Pacific, H. melanostict-us Atlantic Mexican ; 

 H. rhodojns on either side. The last is the commonest species and 

 seems to be an instance of a southerner which, although not goino' 

 on to the plateau itself, ascends the high mountains on its eastern, 

 southern, and western borders, e. g. Citlaltepetl up to 10,000 feet, 

 Oerro de Oaxaca, Nevado de Colima ; it also inhabits the hot low- 

 lands of Agua fria in the State of Vera Cruz. Mostly of dai-k 

 brown and reddish tints and living on or near the ground ; how- 

 ever, some specimens in the epiphytic Tillandsias, or on green 



