were successful, but in the
course of the work five previously unknown hylids were discovered; these
are named and described in this paper. The only species described herein
that I do not know in life is one of _Plectrohyla_ that has been
represented in museum collections for several years but was not obtained
in my own field work.

In this paper I am presenting diagnoses, descriptions, and brief
comments on the relationships of five new species and one subspecies.
More exhaustive accounts will be included in a monograph, now in
preparation, on the Middle American hylids.

For use of comparative material used in the preparation of this paper, I
am indebted to Richard J. Baldauf, Texas Cooperative Wildlife Collection
(TCWC); Charles M. Bogert, American Museum of Natural History (AMNH);
James A. Peters, United States National Museum (USNM); Hobart M. Smith,
University of Illinois Museum of Natural History (UIMNH); Charles F.
Walker, University of Michigan Museum of Zoology (UMMZ); and Ernest E.
Williams, Museum of Comparative Zoology (MCZ). KU refers to the
University of Kansas Museum of Natural History. I am especially grateful
for help in obtaining specimens and data to Linda Trueb, who accompanied
me throughout Mexico and Central America, where we were joined by John
D. Lynch in Costa Rica and Charles W. Myers in Panama. Linda Trueb
offered helpful suggestions in the course of preparing the manuscript,
and David M. Dennis skillfully prepared the illustrations which more
accurately depict the frogs than my written descriptions; both of these
persons have my thanks for their contributions.

Ratibor Hartmann of Finca Santa Clara, Chiriqui, Panama, made possible
our travels to the Rio Changena on the Atlantic slopes of Bocas del
Toro. Field work in Costa Rica was facilitated by the Organization of
Tropical Studies through the courtesy of Stephen B. Preston and Norman
Scott. Rodolfo Hernandez Corzo of the Direccion General de la Fauna
Silvestre provided the necessary permits to collect in Mexico. I thank
each of these persons for his helpfulness and cooperation.

Field work in Mexico and Central America and the associated laboratory
studies on Middle American hylid frogs are supported by grants from the
National Science Foundation (GB-1441 and GB-5818). The field work in
Panama was part of a survey of the herpetofauna of that country carried
out in cooperation with the Gorgas Memorial Laboratory and supported by
the Na