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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

Pteridines, purines and carotenoids in amphibian pigmentation

Stackhouse, Hamilton Lee, 1933- January 1962 (has links)
No description available.
52

A comparative study of the skeletal anatomy of ambystoma jeffersonianum and ambystoma laterale

Branham, Arthur Eugene January 1961 (has links)
There is no abstract available for this thesis.
53

A survey of the amphibians and reptiles of Randolph County, Indiana

McKee, Larry D. January 1970 (has links)
This thesis describes a survey of the amphibians and reptiles in Randolph County, Indiana. The purpose of this survey was to determine what species occur within the county and the relative abundance of each. Secondary importance was placed on habitats, ecology, and breeding seasons of these species.The survey was conducted from August 17, 1968, through October 24, 1969. Most of the collecting was done by the author and his students assistance from Randolph County biology teachers, who saved specimens brought in by their students.This information was correlated with the general topography and with the literature concerning the amphibians and reptiles of Randolph and adjacent counties.
54

Development of the urostyle during metamorphosis in five species of anurans

Branham, Arthur E. January 1977 (has links)
Normal development of the urostyle is described during late stages of metamorphosis in five species of anurans: Xenopus laevis (Daudin), Bufo americanus Holbrook, Pseudacris triseriata (Wied), Hyla chrysoscelis Cope, and Rana pipiens Schreber.Tadpoles of these five species were reared in the laboratory, preserved in Bouin's fixative at various stages of metamorphosis (Gosner stages 34 to 44), and decalcified in 1% HC1 for 48 hours.A block of tissue containing the urotstyle was removed from the tadpole, embedded in paraffin, serially cross-sectioned, stained according to Mallory's trichromatic staining technique, and permanently mounted in Pro-Texx.The developing urostyle of all five species is composed of essentially the same cartilaginous elements: one pair of basidorsals above the notochord and' he hypochord below. Among the five species there is variation in such details as the number of spinal nerve foramina and the degree of fusion of the basidorsals; however, both the hypochord and basidorsals are quite similar in all five genera examined.The development of the urostyle as observed in this study provides insufficient basis for any conclusions about the phylogenetic trends in the five genera.The contradictory descriptions of the developing urostyle found in the literature appear to result from (1) varied methods of study (alizarin-staining of whole specimens or serial cross-sections), (2) the variety of species examined, and (3) the particular stage of development of the tadpole described by an investigator.
55

Systematics of the caecilians (Amphibia: Gymnophiona)

Walsh, Denis M. January 1987 (has links)
Determining the higher level relationships of the modern amphibian order Gymnophiona (caecilians) poses a number of methodological problems. A cladistic methodology is outlined by which the phylogenetic relationships of this group can be determined objectively. Among the possible sister groups analyzed, which include dissorophid temnospondyls, aistopods, nectrideans, lysorophoids, microsaurs, anurans and urodeles, the microsaurs of the families Gymnarthridae and Goniorhynchidae are the most plausible sister group of caecilians, based on cranial osteology. Hence, the three modern orders of amphibians, caecilians, anurans and urodeles, do not constitute a monophyletic assemblage exclusive of all other groups. Ingroup analysis indicates that the Ichthyophiidae is the most primitive living caecilian family. The cladistic analysis suggests that features of the unique jaw apparatus define two groups of caecilians which diverged, phylogenetically, early in the group's history. Morphometric analysis reveals that elements of the jaw apparatus compose a functional suite of features. Aspects of the development, function, and significance of the jaw to miniaturization of the caecilian skull are inferred from the morphometric analysis.
56

Conservation studies of amphibian health at individual, population and landscape scales /

Homan, Rebecca Newcomb. January 2003 (has links)
Thesis (Ph.D.)--Tufts University, 2003. / Director: J. Michael Reed. Submitted to the Dept. of Biology. Includes bibliographical references (leaves 97-114). Access restricted to members of the Tufts University community. Also available via the World Wide Web;
57

Phylogeography, dispersal and movement of Fleay's Barred Frog, Mixophyes fleayi

Doak, Naomi C. January 2005 (has links)
Thesis (Ph.D.) -- Griffith University, 2005. / Facsimile of the author's original dissertation. Pagination of document: xii, 149 leaves. Includes bibliographical references.
58

Amphibian skin peptides which inhibit nNOS structure and binding studies using heteronuclear NMR /

Apponyi, Margit Anneliese. January 2006 (has links)
Thesis (Ph.D.)--University of Adelaide, School of Chemistry and Physics, Discipline of Chemistry, 2006. / "February, 2006" Includes copy of author's previously published article. Bibliography: leaves 145-156. Also available in print form.
59

Relative fitness and behavioral compensation of amphibians in a managed forest /

Blomquist, Sean Michael, January 2008 (has links)
Thesis (Ph.D.) in Wildlife Ecology--University of Maine, 2008. / Includes vita. Includes bibliographical references (leaves 130-165).
60

The germ cell history of Rana cantabrigensis Baird ...

January 1932 (has links)
Thesis (Ph. D.)--University of Michigan, 1930. / Thesis note on label mounted on p. [497] of pt. 1. "Sonderabdruck aus Zeitschrift für zellforschung und mikroskopische anatomie ... 16. band, 3. und 4. ... heft." "Literature cited" at end of each part.

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