The breeding habits and embryonic thermal requirements of the
Cascade frog of Oregon, Rana cascadae Slater, are described. The
limits of temperature tolerance of the pre-feeding stages are from
6° to 27°C for embryos held at constant temperatures. However, for
pre-feeding embryos exposed at different developmental stages for
short durations...
Experimental crosses between Rana pretiosa pretiosa Baird
and Girard and Rana cascadae Slater, resulted in viable hybrids.
Reciprocal differences at the time of fertilization are indicated. A
high level of success in producing viable hybrids can be obtained if
Rana pretiosa pretiosa is the female of the parent species, The...
Developmental series of Rana pretiosa (110 specimens), R.
cascadae (100 specimens) and R. aurora (115 specimens) were bone
stained and cleared in glycerin. The growth and developmental patterns
of the skull and selected bones were followed from the first
appearance of bone through adult stages. The sequential appearance
of the...
Description of anuran larvae with the use of staging tables is
a common practice in the study of frog life-histories, but there has
been no previous description or table of Ascaphus larvae. In comparing
Ascaphus larvae to a simplified staging table for anurans it
was found that these larvae vary...
This report summarizes the results of a field study of a population
of the Pacific mountain beaver, Aplodontia rufa pacifica, from
August 1965 through August 1967. The study site consisted of a 13. 5-
acre grid on a logged over area in the Coast Range Mountains of
Benton County, Oregon....