Thesis (Ph. D.)--Columbia University, 1929. / Bibliography: p. [110]-116.

Thesis (Ph.D.)--University of Rhode Island, 2007. / Includes bibliographical references (leaves 209-225).

Thesis (Ph. D.)--University of Hawaii at Manoa, 2001. / Heading on microfiche: Kajiura, Stephen Michael. Includes bibliographical references (leaves 101-109). Also available on microfiche.

The swell shark, Cephaloscyllium ventriosum Garman (Scyliorhinidae), is an inshore, reef-dwelling, nocturnal species of the Eastern Pacific rim. Reproduction is oviparous. One ovary is developed. Ova are transported through the coelom by cilia, to a single ostium, which serves both oviducts. Egg formation is usually synchronous in both oviducts, and proceeds generally as in other elasmobranchs, but published and new data are combined in a new description of the egg-forming sequence. Photomicrographs show sperm stored in the shell-secreting tubules of the shell gland. This storage allows the production of fertile eggs in the absence of males for some months after mating. A membrane surrounds the embryo and yolk during the early stages of development, contrary to prior descriptions of related species. A chalaza-like structure is attached to this membrane. The young of this and several other oviparous species of sharks possess two dorso-lateral rows of enlarged denticles. In the swell shark, these appear to function in the emergence of the shark from the egg-case. Eggs are preyed upon in nature, possibly by a Stenoglossid gastropod. The sharks form at least two different populations, separated by as little as 30 km. The egg-cases of one population have no tendrils over 2cm.; the other population has long tendrils, to 2 m. Differences are also found in egg size and in the morphometrics of the adult sharks. / Science, Faculty of / Zoology, Department of / Graduate

Thesis (M. Phil.)--University of Hong Kong, 2009. / Includes bibliographical references (leaves 111-126). Also available in print.

Thesis (Ph.D.)--University of Adelaide, Dept. of Environmental Biology, 2001. / Bibliography: leaves 202-238.

The normal depth usage of the juvenile lemon shark, <i>Negaprion brevirostris </i>was determined using data storage tags which logged pressure and temperature.  Sharks were found to predominantly occupy water depths between the surface and 1m.  A diel rhythm and a tidal rhythm were found for the pressure data.  Simultaneous acoustic tracking showed shallow water use despite the availability of deeper areas within the sharks’ home ranges.  All sharks mainly occupied a narrow range of temperatures (29°C - 31°C) at the high end of their range.  Temperature data showed mainly diel rhythms with slight tidal influence.  Pressures and temperatures used by the sharks seemed to be affected by size of home range, individual preference and predator avoidance.  The behaviour of the lesser spotted dogfish <i>Scyliorhinus canicula </i>was investigated during controlled small steps of pressure inside a hypobaric chamber.  Swimming occurred in response to decreasing pressure with increased swimming speed and duration suggesting enhanced sensitivity of the shark pressure sensor within  a narrow range between 39mbar above and down to 195mbar below barometric pressure.  Further studies using a novel tidal tank system showed that <i>Scyliorhinus </i>synchronised their activity with a 12.5 hour tidal cycle but not with a 9  hour cycle.  When different resting depths were made available, they were utilised by dogfish, suggesting an individual preference independent of environmental cues or the presence of the opposite sex.  Isolated vestibular systems were challenged over a range of pressures. Hair cell afferent activity showed responses to sinuosoidal cycles and step changes of pressure.  Temperature effects are complex but were small compared with pressure effects.  Knowledge of the pressure sensor and vertical range used by sharks is essential in the present development of marine protected areas in an attempt to ultimately aid the conservation of sharks.

Typescript. / Bibliography: leaves [212]-219. / xii, 219 l illus., tables

Thesis (Ph. D.)--Catholic University of America, 1942. / Includes bibliographical references (p. 51-52).

Bibliography: leaves 202-238. Gives an overall understanding of embryonic development of Heterodontus portusjacksoni.