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...
The karyotypes of five species of ranid frogs were determined
from metaphase plates of bone marrow cells. The colchicine, hypotonic-
citrate, blaze-dry technique was used to obtain the plates.
Morphometric datawere obtained from the karyotypes and compared
with other species of the genus Rana.
Like most other members of the...
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...
Eggs, larvae and adults of the four subspecies of Hy la regilla
occurring in Oregon as given by Jameson, Mackey and Richmond
(1966) were collected and subjected to salt stress in a series of
graded seawaters.
It was found that in all cases adults were more tolerant than
larvae and...