MEXICAN AMPHIBIANS—TAYLOR AND SMITH 555 
of the Chiapas form of horribilis; and the large tympanum with ele- 
vated border was evident. 
The type was found at night walking (not hopping) about on the 
eround deep in a newly cut cafetal. No other specimens of this group 
were seen under similar conditions, although in more open areas, as 
around human habitations and in cleared fields, they (horribihs) 
were common. , 
BUFO PERPLEXUS Taylor 
Bufo perplecus Tayuor, Univ. Kansas Sci. Bull., vol. 29, 1943b, pp. 347-349, pl. 27, 
figs. 1, 2 (Balsas River near Mexcala, Guerrero). 
The following specimens in the collection are paratypes: U.S.N.M. 
No. 116564, Puente de Ixtla, Morelos, September 5, 1939; U.S.N.M. 
Nos. 116565-116568, Tehuantepec, Oaxaca, May, 1940. 
In this form there is a strong color pattern dimorphism between 
the sexes. The species is smaller than B. marmoreus, with which it 
is sometimes confused. Its distribution as known at present is 
Morelos, Guerrero (northern and central parts), Oaxaca, and Chiapas— 
all on the Pacific drainage. 
BUFO PUNCTATUS Baird and Girard 
Bufo punctatus Bairp and GrRARD, Proc. Acad. Nat. Sci. Philadelphia, vol. 6, 1852, 
p. 173 (Rio San Pedro, tributary of the Rio Grande del Norte, Texas). 
The following specimens, 13 in number, are in the collection: 
U.S.N.M. No. 106144, 31 miles south of Chihuahua, Chihuahua, 
October 26, 19388; U.S.N.M. No. 115487, Sabinas Hidalgo, Nuevo 
Leon, April 29, 1939; and U.S.N.M. Nos. 115488-115498, 15 miles 
west of Galeana, Nuevo Leén, October 13-14, 1939. 
All the specimens show black punctations on chin, breast, and 
anterior part of abdomen. They usually lack the reddish spots 
present in western American specimens. The single male has the 
vocal slit sinistral. 
BUFO MARMOREUS Wiegmann 
PuaTE 23, Fies. 1, 2 
Bufo marmoreus WIEGMANN, Isis von Oken, vol. 26, pt. 7, 1833, p. 661 (Veracruz, 
México). 
The collection contains five specimens. Four young individuals 
are from Guerrero, México: U.S.N.M. Nos. 116560-116561, Tierra 
Colorada,’ August 31, 1939; and U.S.N.M. Nos. 116562-116563, 
Acapulco, September 3, 1939. These are females having the typical 
coloration. A single specimen, U.S.N.M. No. 116569, is from 
Escurana, Oaxaca (15 km. west of Tehuantepec), May, 1940. 
The sexual dimorphism in this species is especially great. In a 
series we have examined, in the E.H.T.-H.M.S. collection, we find 
that the females have a median, rather broad dorsal stripe, with 3 
