Righting behavior was examined in the asteroids Henricia
leviuscula and Leptasterias aequalis by repeating a standard laboratory
righting trial with a large number of individuals of each species,
and analyzing the observations made by statistical methods. Detailed
observations on the righting method, including leading pairs of
arms and righting time...
Rhabdocoels of the genus Paravortex are parasites of marine
molluscs. The bent-nosed clams, Macoma nasuta(Conrad, 1837) of
Yaquina Bay, Lincoln County, Oregon are commonly infected with a new
species of Paravortex. The morphology of the adult worm has been
described and it has been compared to the other three species...
The pea crab Fabia subquadrata is frequently found as a symbiont
of mussels, living within the mantle cavity. This study examined
the nature of this symbiotic relationship by recording the pattern
of distribution of individuals in a mussel bed, testing responsiveness
to host secretions, and observing the feeding mechanics and...
Morphological changes which occur during tentacle formation
have been described in the colonial athecate hydroid Cordylophora
lacustris. These changes involve an outpocketing of mesoglea into
a finger-like extension of the hydranth. Gastrodermal cells line the
inside of this extension of mesoglea while ectodermal cells cover the
outside. Electron micrographs reveal...
Osmotic and ionic regulation was studied in the North
American crayfish Pacifastacus leniusculus (Dana), stepwise acclimated
to increasing salinities. Stepwise acclimation involved transferring
crayfish at 48 hour intervals from freshwater to 100% seawater
in 20% increments. In experiments where 70% seawater was
used, animals were moved directly from 40 to...
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...
Metabolic rate-temperature responses of three related
species of sea urchins were determined using oxygen consumption
rate measurements. The three species used were Strongylocentrotus
purpuratus, Strongylocentrotus franciscanus, and Allocentrotus
fragilis. All measurements were made using an oxygen
macro-electrode, physiological gas analyzer, and sealed respiratory
container. Two series of experiments--field-acclimatized and
temperature-acclimated--were...
The syllid polychaete Autolytus varius reproduces in the spring
and early summer in Yaquina Bay, Oregon, The fertilized female
epitokes, or Sacconereis, carry the developing eggs and larvae in a
ventral sac until the larvae are ready to be released; incubation
lasts 14 to 18 days in the laboratory, The...
The patterns of cell proliferation in the choroid plexuses of
embryonic and post-natal hamsters were studied by means of auto-radiography
(H³-thymidine). In addition, the PAS technique was
used to determine the times of first appearance, relative amounts,
location, and times of disappearance of glycogen free the plexuses.
Many mitotic figures...
Earthworms are capable of osmotic and ionic regulation while
living in a dilute balanced salt solution. When transferred from soil
to pond-water (PW) their body weight increases by 15 percent due to
a net uptake of water.
This results in an initial dilution of the
coelomic fluid (CF).
Subsequently, Na...
The western Plethodon include vandykei vandykei, v. idahoensis,
larselli, dunni,vehiculum, stormi, elongatus, and an undescribed
form referred to as the "unstriped" Plethodon. These
salamanders have been placed into three species groups: the
Vandykei group, the Vehiculum group, and the Elongatus group.
Range maps are provided and geographic variation is discussed...
The integumental histology of Taricha granulosa (Skilton) has
been investigated with special attention being given to the seasonal
variations associated with terrestrial and aquatic habitats.
The epidermis consists of a stratified squamous epithelium,
four to seven cell layers thick, with one to two layers being cornified.
The dermis is composed...
This study investigated several physiological aspects of the
water economy of the Sage Sparrow, Amphispiza belli nevadensis,as
they relate to the ability of this species to inhabit xeric desert environments.
When maintained in captivity on a dry diet without
drinking water, Sage Sparrows gradually lost weight and died. During the...
The anemone Anthopleura xanthogrammica varies in color from
bright green to muddy brown. However, individuals found in caves
are white. White specimens of Anthopleura xanthogrammica collected
from dark caves along the Oregon coast were subjected to various
experiments to determine if these cave dwelling animals carried any
cells of 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...
Acid and alkaline phosphatase was localized histochemically in the intestinal epithelium and excretory duct respectively in fresh
frozen sections of Fasciola hepatica. Polyphenol oxidase was
localized in the vitellaria, vitelline ducts and egg-shells. The distribution
and nature of esterases was examined histochemically. Acetyl-cholinesterase
was observed in the tegument, neural ganglia,...
This histochemical study deals with the changing patterns of
glycogen in the uterus of the immature virgin, cycling virgin, and
post partum (non-lactating) golden hamster (Mesocricetus auratus
Waterhouse). The periodic acid-Schiff technique was used for the
histochemical localization of glycogen in the uterus of the immature,
cycling and non-lactating post...