MEXICAN AMPHIBIANS—TAYLOR AND SMITH 565 
MICROBATRACHYLUS PYGMAEUS (Taylor) 
Eleutherodactylus pygmaeus Tayuor, Trans. Kansas Acad. Sci., vol. 39, 1936 
(July 2, 1937a), pp. 352-354, pl. 1, figs. 3, 4 (Rodriguez Clara, Veracruz). 
Microbatrachylus pygmaeus Taytor, Univ. Kansas Sci. Bull., vol. 26, No. 15, 
1940g, pp. 500-501. 
Two large series were taken, one from the north in the regions about 
Potrero Viejo and Cuautlapan, Veracruz, the other from the south, in 
Chiapas. A smaller series, somewhat less typical, was collected in 
Guerrero. In all, 237 specimens were secured. 
Potrero Viejo specimens (U.S.N.M. Nos. 116840-116842; 116864— 
116870), collected from December 13, 1938, to January 9, 1939, are 
relatively uniform in character. ‘There is the merest trace of a web 
between the toes; the digits are moderately dilated at the tip; and the 
skin is slightly pustular and corrugated. There is usually a single 
indistinct supernumerary tubercle on the sole in advance of the outer 
metatarsal tubercle. 
In specimens from Cuautlapan, collected from January 4 to 16, 
1939, and in January and February, 1940 (U.S.N.M. Nos. 116871- 
116875) the skin appears very much rougher, presumably because of 
its long preservation in strong formalin. 
The southern specimens are from the following localities: Oaxaca: 
U.S.N.M. No. 116826, Matias Romero, January 25, 1940. Cutrapas: 
U.S.N.M. Nos. 116831-116833, La Esperanza, April 11 and May 18, 
1940; U.S.N.M. Nos. 116834-116837, Colonia Hidalgo, April 14, 
1940; U.S.N.M. Nos. 116838-116839, Colonia Soconusco, April 14 
and May 10, 1940; U.S.N.M. Nos. 116843-116854, Las Nubes, 
Cerro Ovando, April 15, 1940; U.S.N.M. Nos. 116828-116830, Finca 
Judrez, May 8-10, 1940; U.S.N.M. No. 116827, La Magnolia, May 
23, 1940; U.S.N.M. Nos. 116855-116863, Salto de Agua, Mount Ovan- 
do, April 18 to May 19, 1940. 
These latter specimens vary more among themselves than the 
northern forms, perhaps because they are from a greater variety of 
elevations. 
The skin is apparently less pustular and less corrugated than in those 
from the northern part of its range, but this may be due to method of 
preservation. A few specimens have an irregular, diagonal, black- 
edged whitish stripe on the side. The single supernumerary tubercle 
on the sole is absent and there is usually a little more pigment on the 
venter. 
The series from Guerrero, U.S.N.M. Nos. 116817—116825, August 
31, 19389, resembles the specimens from Veracruz more than those 
from Chiapas. The skin is usually pustulate and corrugated, and the 
pigment on the venter is not dense. One specimen has a broad median 
light stripe. This same character has been observed in two Cuautla- 
pan, Veracruz, specimens, but it is of rare occurrence. 
