3. The relative size of the supratympanic crest is highly
variable in all samples examined.

[Illustration: FIG. 3. Adult male of _Bufo perplexus_ from Apatzingan,
Michoacan. x 1.5.]

[Illustration: FIG. 4. Adult male of _Bufo marmoreus_ from Pomaro,
Michoacan. x 1.5.]

[Illustration: PLATE 1

Hatchling of _Pseudoeurycea belli_ from San Juan de Parangaricutiro,
Michoacan. x 8.]

[Illustration: PLATE 2

FIG. 1. Nest and eggs of _Pseudoeurycea belli_ beneath a
rock at San Juan de Parangaricutiro. Approx. natural size.

FIG. 2. Multiple egg clutches of _Phyllomedusa
dacnicolor_ from Coalcoman, Michoacan. 1/3 x.

[Illustration: PLATE 3

FIG. 1. Adult male of _Tomodactylus angustidigitorum_
from Paracho, Michoacan. x 4.

FIG. 2. Adult male of _Tomodactylus fuscus_ from Los
Cantiles, Michoacan. x4.

[Illustration: PLATE 4

FIG. 1. Adult male of _Tomodactylus nitidus_ nitidus from
Tuxpan, Michoacan. x.

FIG. 2. Adult male of _Tomodactylus nitidus orarius_ from
Tecolapa, Colima. x 4.]

[Illustration: PLATE 5

FIG. 1. Adult male of _Tomodactylus nitidus_ petersi from
Apatzingan, Michoacan. x 4.

Fig. 2. Adult male of _Tomodactylus rufescens_ from Dos
Aguas, Michoacan. x 4.]

[Illustration: PLATE 6

FIG. 1. Adult male of _Hypopachus caprimimus_ from
Tuxpan, Michoacan. x 2-1/2.

FIG. 2. Adult male of _Hypopachus oxyrrhinus ovis_ from
Tangamandapio, Michoacan. x 3.]

4. A distinct, pale-colored, diagonal lateral stripe is
found in females only from localities outside of the
Balsas-Tepalcatepec Basin; females from the basin have a
spotted dorsum.

5. Males from the Balsas-Tepalcatepec Basin usually have a
broad middorsal line that is yellow or pale tan; those from
outside the basin have either a narrow middorsal line or
none.

6. Males from the Balsas-Tepalcatepec Basin have low,
scattered dorsal tubercles (Fig. 3); males from outside the
basin have a concentration of tubercles in a broad band on
the back (Fig. 4).

Therefore the nature of the cranial crests is of little value in
separating two populations, but the color pattern of the females and the
nature of the dorsal tubercles of the males do show distinct
differences. Furthermore, certain differences in size and proportion are
evident; _Bufo marmoreus_ is a slightly larger toad and has a relatively
longer tibia and longer head than _perplexus_ (Table 2).

TABLE 2.--CO