, on
June 21, 1966. Males were calling from depressions in decaying logs and
stumps, in forked stems, and from leaves of broad-leafed plants near
the pond. Males were observed in late July and early August calling
from _Calathea_ and _Heliconia_ leaves at the edge of a pond in the wet
forest of the Osa Peninsula. William E. Duellman informed me that he
collected calling males in January at El Real, Darien, and in March at
Almirante, Bocas del Toro, Panama. Taylor (1952) found calling males in
June at Turrialba, Cartago Province, Costa Rica, and Dunn (1931a)
observed males calling in July, November, and December in Panama.
Gravid females have been found from April to August. Breeding
activities of _Hyla boulengeri_ always seem to be associated with
temporary ponds; in Central America breeding apparently takes place
throughout most of the year.

The mating call of _Hyla boulengeri_ consists of one short, moderately
low-pitched note. Each note has a duration of 0.24 to 0.47 second and
is repeated at intervals of one second to several minutes. The notes
have 80 to 120 pulses per second, a fundamental frequency of about 70
cycles per second, and a dominant frequency of 2,840 cycles per second
(Table 2, Pl. 3A).

The eggs are deposited in a mass in the water. No information is
available concerning early development. Tadpoles in advanced stages of
development were found in a temporary pond at Rincon de Osa, Puntarenas
Province, Costa Rica. The pond was about 10 cm. deep, had a muddy
bottom and lacked vegetation. Three recently metamorphosed young were
found in mid-August, 1966, on grass at the edge of another temporary
pond in the forest.

_Tadpoles_--Twelve tadpoles are available. These were collected at
Rincon de Osa, Puntarenas Province, Costa Rica. The maximum size
represented is 34.0 mm., total length (stage 42 of development).

A typical tadpole in stage 36 of development (KU 104295) has a body
length of 12.0 mm., tail length of 20.0 mm., and total length of 32.0
mm. Other characters are as follows: depth of tail equal to length of
body; body deeper than wide; distance between eye and nostril equal to
that between nostril and tip of snout; mouth anteroventral, upper and
lower lips bare; papillae present laterally; tooth rows 2/3; upper rows
about equal in length; first upper row slightly, and second upper row
widely, interrupted medially; lower rows about equal in length, shorter
than upper rows; third lower row con