Record Details
Field | Value |
---|---|
Title | Seasonal variations in the integumental histology of the newt, Taricha granulosa (Skilton) |
Names |
Gibson, Linda Suzanne
(creator) Dornfeld, Ernst J. (advisor) |
Date Issued | 1969-03-10 (iso8601) |
Note | Graduation date: 1969 |
Abstract | 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 of two layers. The outer stratum spongiosum contains chromatophores, capillaries, smooth muscle cells, fibroblasts and skin glands. The inner stratum compactum is composed of horizontal bundles of collagenous fibers. The granular and mucous glands are simple alveolar glands possessing an intercalary region and a duct. The alveolar wall of the granular gland is comprised of a columnar epithelium, muscle layer, and connective tissue sheath. The mucous gland alveolar wall consists of two layers, a cuboidal to columnar epithelium and a connective tissue sheath. The roughness of the terrestrial skin is due to two types of tubercles. Major tubercles are caused by thickening of the epidermis over a dermal papilla, while minor tubercles are merely thickenings of the epidermis. The aquatic epidermis is less cornified than that of the terrestrial. It also shows a slight increase in height, which is particularly evident in the tail. The swelling of the body and the enlarged tail of the male in the aquatic stage are caused by an edema of the stratum spongiosum. This stage also shows an increase in sub-epidermal capillaries and an increase in the activity of the mucous glands. Both aquatic and terrestrial animals have granular glands of equal secretory activity. The aquatic phase possesses fewer glands per unit area of skin due to the increase in the size of the dermis. Terrestrial newts have the smallest granular glands and aquatic newts the largest, though there is a strong overlap of granular gland volume in the two stages. The aquatic phase has the largest mucous glands. |
Genre | Thesis/Dissertation |
Topic | Newts |
Identifier | http://hdl.handle.net/1957/46699 |