List of Titles

Colour vision of the citrus psylla Trioza erytreae (Del Guercio) (Homoptera: Psyllidae) in relation to alightment colour preferences

- Urban, Alan Joseph

Authors: Urban, Alan Joseph
Date: 1977
Subjects: Trioza , Homoptera , Jumping plant-lice , Color vision
Language: English
Type: Thesis , Doctoral , PhD
Identifier: vital:5885 , http://hdl.handle.net/10962/d1013286
Description: The colour vision of adult citrus psylla, Trioza erytreae, was investigated in the laboratory using the behavioural parameters: alightment and walking. Light green flushing leaves (under which the nymphs develop) were significantly preferred, visually, to dark green mature leaves for alightment. Diffuse reflectance spectroscopy showed (when expressed in the parameters of human colour vision) that flush has a very slightly longer dominant wavelength, and roughly double the reflectance and purity. Alightrnent frequency correlated almost equally well with "purity" (as noted by Moericke, 1952 et seq., in "yellow-sensitive" aphids) as with the aphidological colour parameter "long/short ratio" developed by Kennedy et al. (1961). Elucidation of the mechanism underlying the citrus psylla's alightment colour preference was initially attempted with a printed spectrum and several paint series of measured spectral characteristics. It was clear that T.erytreae belongs to the "yellow-sensitive" group of Homoptera, but it was impossible to distinguish which pararneter(s) of colour the psyllids were responding to. Phototactic (walking) response to the individual parameters of colour was therefore measured using a monochromator. The phototactic action spectrum (against wavelength) was tri-modal, with peaks in the yellow-green (YG), blue (B), and ultra= violet (UV). Rate of phototaxis was not influenced by bandwidth (roughly equivalent to purity), but was proportional to intensity (roughly equivalent to reflectance). To investigate the influence of the above three wavelength regions on alightment, use was made of a very simple flight chamber incorporating a target of coloured light. Yellow-green and UV light both independently stimulated alightment . Their effect was additive. Different thresholds indicated distinct YG and UV receptor systems. Blue light alone did not stimulate alightment, and was strongly alightment-inhibitory in combination both with YG and with UV light. On the basis of the above physiological/behavioural findings, a new alightment formula was drawn up for describing the hamopteran's apparent manner of alightment determining integration of surface reflectance. The flush preference and alightment distributions on the series of artificial surfaces were found to correlate slightly more accurately, on average, as well as more consistently, with the new formula than with previously-available colour parameters. These findings are placed in perspective to the literature, and their possible economic relevance is discussed.
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Conscientious objection and the concept of worship

- Moulder, James Edward

Authors: Moulder, James Edward
Date: 1977
Subjects: Conscientious objectors -- Law and legislation -- South Africa , Conscientious objectors -- South Africa , Conscientious objection , Conscientious objection -- Religious aspects
Language: English
Type: Thesis , Doctoral , PhD
Identifier: vital:2749 , http://hdl.handle.net/10962/d1013555
Description: [Preface] " ... the focus of this inquiry is limited to some of the connections between conscientious objection in South Africa and the worship and imitation of Christ. More specifically, at the most general level this essay is an attempt to explore six questions: What kind of conscientious objection does South African law allow? Why are some conscientious objectors only conscientious noncombatants? Why are some Christians conscientious noncombatants? Is it appropriate to worship Christ? Does Romans 13 undermine conscientious noncompliance? And is there a prescription for servile compliance? These are, however, not the only questions which are raised in this essay. Nor are they the only questions which can and need to be asked. But they are the questions which interest me. In addition, they have not received as much attention as they deserve".
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Death and transcendence in northern European art

- Pratt, S R

Authors: Pratt, S R
Date: 1977
Subjects: Death in art , Art -- Europe, Northern
Language: English
Type: Thesis , Masters , MFA
Identifier: vital:2505 , http://hdl.handle.net/10962/d1015230
Description: [From Introduction]. Time has revealed two distinct tendencies in the history of thought and art in Europe. That development in European culture which began in Ancient Greece is marked by a positive confidence in the relationship of man to his world. Parallel with but in opposition to this development is a separate progression in culture. The continuity of art in Northern Europe appears to be associated with the adherence of Northern man to a negative, fatalistic sense of being - to a spirit which is in conflict with a hostile violent environment. The purposo of this investigation is to determine, through art the nature of this sense of being in Northern Europe. No direct definition would be capable of conveying the fullest meaning of that spirit. lt is a feeling. To understand this morbid fatalism, it is therefore necessary to refer to the pre-Christian religion of the Germanic Barbarians - through which the Northern spirit manifested itself in the form of ragnarök. Ragnarök which can be translated as a moaning obscurity, shadows, twilight, fateful destiny, was a term used by Nordic bards in its broadest sense to describe the end of the world - the inevitable destruction of life.
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Eating Cape apples in London

- Rumney, Reg

Authors: Rumney, Reg
Date: 1977
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/460643 , vital:76024 , https://journals.co.za/doi/epdf/10.10520/AJA00284459_339
Description: New Coin is one of South Africa's most established and influential poetry journals. It publishes poetry, and poetry-related reviews, commentary and interviews. New Coin places a particular emphasis on evolving forms and experimental use of the English language in poetry in the South African context. In this sense it has traced the most exciting trends and currents in contemporary poetry in South Africa for a decade of more. The journal is published twice a year in June and December by the Institute for the Study of English in Africa (ISEA), Rhodes University.
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Examination of the theological education of Africans in the Presbyterian, Methodist, Congregational and Anglican churches in South Africa from 1860 to 1960

- Gqubule, T Simon N

Authors: Gqubule, T Simon N
Date: 1977
Subjects: Theological -- Study and teaching Theological seminaries -- South Africa Theology -- Study and teaching -- Protestant churches
Language: English
Type: Thesis , Doctoral , PhD
Identifier: vital:1254 , http://hdl.handle.net/10962/d1012082
Description: This is in many ways a limited study. The first limitation is that only four denominations, the Anglican, Congregational, Methodist, Presbyterian, are considered and nothing is said about the work of the Moravians, Lutherans, Roman Catholics and the Dutch Reformed Churches in the field of theological education. The second limitation is that it is a study of theological education as distinct from general, industrial and other forms of education. All the forms of theological education considered here were run at missionary institutions that offered other forms of education and prepared their students for public government examinations with certain government conditions to be met. Moreover, a certain standard of general education was required before candidates were admitted to the theological course. Therefore, theological education was constantly dependent upon and was influenced by secular education and government regulations concerning secular education. For that reason the first chapter is a very brief survey of White Education in the Cape and African education in all four provinces from the beginning to 1915, the year before Fort Hare opened its doors to students seeking 'higher' education. The second chapter discusses the educational programme of Lovedale because Lovedale generally determined the whole of African education in the Cape. When Lovedale and the Methodists transferred their training to the South African Native College at Fort Hare, theological students had to abide by educational and other regulations of the university College. Chapters III and IV deal with the Methodist theological schools and the courses followed at Fort Hare. The third limitation of this study is that it is a study of the theological education of Africans, which category includes Coloureds and Indians because in the four churches under review they were trained together with Africans. In all churches under review here the theological education of whites was done in an unsatisfactory and ad hoc way. Many men were ordained without a satisfactory theological education. They were given some training by their superintendents, bishops or other men appointed to do the job in addition to their own normal duties. A few were sent overseas and many went through some arrangement within this country. St Paul's Theological College for Anglicans was opened in 1902. A start was made with the training of white Methodist Candidates for the ministry in the buildings of the Wesleyan High School for Girls in Grahamstown, in July 1928, under the Rev. James Pendlebury, B.A. (a supernumerary). Dr. William Flint who started the Methodist College as Principal, at Bollihope, Cape Town, in 1929, was seventy-five years of age when he opened the new Sbllege. From 1948 white theological students of the Methodist, Presbyterian and Congregational Churches have been trained at Livingstone House, Rhodes University, Grahamstown. .The final limitation is that this study ends at the close of 1960 and thus omits some of the exciting developments in theological education that have taken place since then. These limitations and demarcations were, however, necessary in order to focus attention on a small area where the main problems could be seen clearly, unencumbered by lesser issues. Where the training was run on denominational lines, it seemed necessary wherever possible to give a chapter to each denomination, and to attempt to pull the threads together in a concluding chapter.
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Explanation of the geological map of the country east of Kariba

- Broderick, T J

Authors: Broderick, T J
Date: 1977
Subjects: Geology -- Kariba, Lake (Zambia and Zimbabwe) -- Maps , Geology -- Kariba, Lake (Zambia and Zimbabwe)
Language: English
Type: Thesis , Masters , MSc
Identifier: vital:5075 , http://hdl.handle.net/10962/d1014650
Description: The area covers part of the western end of the Zambezi Metamorphic Belt as it is known in Rhodesia. Most of the rocks are paragneisses of various ages that have suffered a long and complex history which has taken them into the highest facies of metamorphism and into the realm of granitization. Only the Karoo sediments of the Zambezi Valley are unaffected by these metamorphic events. From the scanty geochronological results obtainable from the north of Rhodesia, the history of this area started more than 2 500 million years ago. In the east and south-east of the mapped area are a group of highly migmatized granitic gneisses which represent a continuation westwards of similar rocks found in the area described in Bulletin 51 by Wiles (1961}. These Urungwe Paragneisses are regarded as forrning the basement on which all other rocks in the area lie, although their relationship with the Basement Complex is unknown. Climatically Kariba is hot and humid. Mean summer temperatures average 30°C (86°F), with temperatures in October that often exceed 40°C (100°F). Away from the Lake the humidity decreases and the increased altitudes above the Escarpment have a cooling effect. The township's mean annual rainfall is 665 millimetres (26,2 inches), most of which falls in the months between November and February. Basically. the area is well timbered but population pressures in the tribal areas, and depredation by elephants elsewhere, have made serious inroads upon the natural vegetation. The gneissic terrain above the Escarpment is characterized by mufuti trees (Brachystegia boehmiz). The baobab (Adansonia digitata) is common in the larger river valleys and in the low-lying area surrounding the lake shore where it occurs together with mopane (Colophospermum mopane) and thick jessie bush. In the river valleys, trees typical of the Zambezi Valley are common and include the tamarind (Tamarindus indica), mumvey (Kigelia africana) and Steculia species. Buffalo beans (Mucuma coriacea) are not uncommon in grassy river-beds. Physiographically, the area can be subdivided into three distinct regions, all of which have a marked geological control. They are- (1) The fault-lined Gwembe trough which has subsequently been inundated by the waters of Lake Kariba to an average altitude of 487 metres (1 600 feet) above sea level since the completion of the dam across the upstream entrance to the Kariba Gorge in 1960. The fiat land that now forms part of the lake shore is underlain by sediments of Karoo age and these, in the mapped area, occupy the Charara and Gachegache Basins, that lie to the north and south respectively of the Msango Range. These fiat-lying areas give way sharply to the gneissic terrain of the Zambezi Metamorphic Belt along the fault-lined Zambezi Escarpment. (2) The northern boundary of the area and the Msango Range are underlain by metasediments of the Makuti Group. The relief is strongly influenced by the regional geological structure of these complexly folded rocks with resistant meta-arkose and quartzite forming the sharp ridges and metapelites occupying the valleys. The ridges and valleys trend eastwards in the Msango Range, but along the northern boundary they trend north-westwards. (3) The linear topographic features of the Makuti Group terrain give way southwards to the older gneisses along an abrupt scarp edge, the base of which is marked by the Tsororo River. This terrain of gneisses is very rugged and highly dissected above the Zambezi Escarpment until it flattens out, at about 900 metres (2 950 feet) above sea level, into the Urungwe Tribal Trust Lands. In the rugged country above the Escarpment, granulites of the Piriwiri Group stand out above the gneisses as steep-sided conical bills. The country rises in a series of fault-lined steps to its highest point, at Nyamangwe trigonometrical beacon, which stands at 1 336 metres (4 382 feet) above sea level.
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Feeding ecology of the cichlid fish Sarotherodon Mossambicus in Lake Sibaya, KwaZulu

- Bowen, Stephen H

Authors: Bowen, Stephen H
Date: 1977
Subjects: Cichlids -- Ecology , Fishes -- Ecology -- South Africa -- KwaZulu-Natal -- Sibaya, Lake
Language: English
Type: Thesis , Doctoral , PhD
Identifier: vital:5837 , http://hdl.handle.net/10962/d1009688 , Cichlids -- Ecology , Fishes -- Ecology -- South Africa -- KwaZulu-Natal -- Sibaya, Lake
Description: The feeding of the cichlid fish Sarotherodon mossambicus in Lake Sibaya, KwaZulu, was studied in relation to various biotic and abiotic features of the l ake environment from January, 1973 to July, 1975. The primary goal of the study was to determine the cause of stunting and poor condition of adults in this population. Juvenile and adult S. mossambicus feed on a mixture of detritus, bacteria and diatoms that occurs as a flocculent layer on sand substrates throughout the lake. Concentrated gastric acid, commonly at pH values of 1.5 and lower, lyses diatoms and bacteria which are subsequently digested in the intestine. This is the first report of digestion of bacteria by a fish, and the nutritional significance of the finding is discussed. Juveniles feed predominantly on shallow sand terraces found along the margin of much of the lake, while adults usually feed in offshore waters at depths of 3 m and greater. Benthic floc from feeding areas of juveniles and adults have similar concentrations of organic matter, total carbohydrate, soluble carbohydrate and calories, but differ markedly in respect to diatom and protein concentration. Diatom concentrations are generally high in terrace floc but are consistently low in floc from deep water. Protein concentration of benthic floc decreases with increasing depth from 0 - 5 m. Partial correlation analysis shows that protein and diatom concentrations have no correlation independent. of their common relationship to depth, and the evidence implicates detrital bacteria as the primary source of protein in benthic floc. Probable causes of the observed distributions of diatoms and protein are discussed. The protein content of benthic floc profoundly influences its nutritional value. A comparison with available data on animal nutrition shows that the ratio of digestible protein to digestible energy in floc in the shallows is high enough that this food resource would be expected to support good growth, but the ratio for deep water floc is so low that it would be expected to result in conspicuous malnutrition. Thus, inadequate dietary protein is identified as the principal cause of stunting and poor condition of adult S· mossambicus in Lake Sibaya; It is argued that the ratio of digestible protein to digestible calories can be expected to determine the food value of particulate organic matter that includes amorphous detritus in other ecosystems. Despite stunting and poor condition of adults, S. mossambicus are abundant in Lake Sibaya. The precocious breeding of this population is discussed as an adaptation that allows it to maximize reproductive output given the limited resources available to adults. Juvenile S. mossambicus perform daily movements from deep water onto the terraces where they feed and then back into deep water. During periods of relatively low lake level when terrace waters were usually less than 1.5 m deep (1-73 to 1-74), juveniles were present on the terrace throughout daylight hours. At relatively high lake levels (7-74 to 8-75), juveniles were present on the terraces for only about five hours following sunset. Periods of heavy wave action interrupt feeding activity and result in reduced numbers of fish in terrace waters. The possible roles of predator avoidance and temperature in determination of daily feeding behavior are discussed. Daily energy assimilation by juveniles, estimated by a field technique, is approximately 115 cal per g fish dry weight.
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Gewestelike verskynsels in die Afrikaanse spreektaal van Oos-Kaapland met spesiale verwysing na Albanie

- Van der Mescht, J W F (Johannes Willem Frederik)

Authors: Van der Mescht, J W F (Johannes Willem Frederik)
Date: 1977
Subjects: Afrikaans language -- Dialects
Language: Afrikaans
Type: Thesis , Masters , MA
Identifier: vital:3643 , http://hdl.handle.net/10962/d1014568
Description: By 'n dialekgeografiese studie van hierdie aard sal dit by uitstek die verstandigste wees om te begin by 'n omgewing waarin die ondersoeker gebore is en grootgeword het. Die omgang van die ondersoek en die uitgestrektheid van die gebied wat hierby betrokke is maak dit egter vir 'n boorling net so moeilik as vir 'n goeie waarnemer uit enige ander spraakgebied wat ook daartoe in staat behoort te wees om bepaalde foniese, leksikale, grammatiese, semantiese en sintaktiese verskynsels, eienaardighede en tendensies in die spreektaal op te merk. My bekendheid en omgang met Afrikaanssprekendes in hierdie streek wil ek nietemin kortliks soos volg aandui: (a) Wat vir hierdie studie as "randgebiede" beskou kan word. Gebore en opgegroei in Willowmore (19 jaar), onderwysopleiding op Graaff-Reinet (3 jaar). Onderwysondervinding In die distrik Steytlerville (2 ½ jaar). (b) Die eintlike ondersoekgebied. Onderwysondervinding in Oos-Londen en omgewing (6 jaar) , Grahamstad (10 ½ jaar) afgesien van talle lisensies in Oos-Londen en Port E1izabeth en besoeke aan omliggende dorpe en distrikte.
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Iago's handkerchief song

- Butler, Guy F

Authors: Butler, Guy F
Date: 1977
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/458847 , vital:75775 , https://journals.co.za/doi/epdf/10.10520/AJA00284459_339
Description: New Coin is one of South Africa's most established and influential poetry journals. It publishes poetry, and poetry-related reviews, commentary and interviews. New Coin places a particular emphasis on evolving forms and experimental use of the English language in poetry in the South African context. In this sense it has traced the most exciting trends and currents in contemporary poetry in South Africa for a decade of more. The journal is published twice a year in June and December by the Institute for the Study of English in Africa (ISEA), Rhodes University.
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Instability in the magnetotail

- English, Daniel Rowe

Authors: English, Daniel Rowe
Date: 1977
Subjects: Magnetotails
Language: English
Type: Thesis , Masters , MSc
Identifier: vital:5425 , http://hdl.handle.net/10962/d1011764 , Magnetotails
Description: The magnetic induction field due to the Earth only would, if undisturbed by any outside agency, resemble macroscopically the field due to a magnetic dipole. Hcwever the field is disturbed by the interplanetary magnetic field, of which the most important component is that of the Sun. If the Sun's magnetic field were effectively steady, it would also be a dipole field, and approximately constant in the region within about twenty earth radii from the earth. Also, if we treat the Sun as a dipole, its dipole axis is roughly normal to the ecliptic plane. The Earth, treated as a dipole, has an axis which is inclined to the normal to the ecliptic plane at an angle which varies daily from a few degrees to nearly a third of a right angle. However, in this paper, it is proposed to treat both dipole axes as contra-parallel and effectively normal to the ecliptic plane, so that a general idea of the combined field can be obtained. Then the effect of a steady field due to the Sun, on the Earth's field would be the formation of a "neutral ring" surrounding the Earth; that is, a closed "neutral line", this being a line of points at each of which the net nagnetic induction is zero. As the point of observation passes through this line, the field changes direction. Intro. p. v.
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Jewish South Africans: a sociological view of the Johannesburg community

- Dubb, Allie A

Authors: Dubb, Allie A
Date: 1977
Subjects: Jews -- South Africa -- Johannesburg Johannesburg (South Africa) -- Social conditions
Language: English
Type: Book , Text
Identifier: http://hdl.handle.net/10962/1697 , vital:20217 , ISBN 0868102253
Description: The South African Jewish community is embedded in the wider one of white, mainly English-speaking South Africa in a way in which Eastern European Jews were not, and the individual may decide for himself the nature and extent of his Jewish involvement. In South Africa, then, 'being Jewish' varies within wide limits: it may be little more than an accident of birth minimally affecting a person's behaviour; it may -be expressed primarily in support of Jewish institutions and philanthropies; or it may have much the same connotations as it had in Eastern Europe. What being Jewish means in the South African context and, more specifically, in Johannesburg, is the problem to which the present study is addressed. Its aim is to distinguish the various elements of Jewishness, and to discover the manner in which they find expression among those who regard themselves as Jews. It is a study of identification: that is, of the behaviour, sentiments, beliefs, values and attitudes which derive from, and express identity with, the Jewish group, its culture, religion and peoplehood. , Digitised by Rhodes University Library on behalf of the Institute of Social and Economic Research (ISER)
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Pitch learning and the implications for music education

- Byrd, Audrey S

Authors: Byrd, Audrey S
Date: 1977
Subjects: Musical pitch -- Instruction and study
Language: English
Type: Thesis , Doctoral , PhD
Identifier: vital:2627 , http://hdl.handle.net/10962/d1001867
Description: A study of pitch learning must outline first the procedures involved in such learning and then identify specific factors appearing to influence the learning of pitch. Once identified, each factor can then be evaluated by controlled experiment before confirming its influence. Since it is what is heard and perceived that is learnt, I have started with the process of Hearing and Perceiving, for as Arnold Abramovitz, Senior Lecturer in Psychology at Cape Town says, “the reception, processing and interpretation of acoustic symbols constitutes some of the most elusive and complex phenomena to attempt to examine, gauge and measure, due partly to the transient, ephemeral nature of sound itself.”
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Pitch learning and the implications for music education

- Byrd, Audrey S

Authors: Byrd, Audrey S
Date: 1977
Subjects: Musical pitch -- Instruction and study
Language: English
Type: Thesis , Doctoral , PhD
Identifier: vital:2675 , http://hdl.handle.net/10962/d1007403
Description: From introduction: A study of pitch learning must outlina first the procedures involved in such learning ar~d then identify specific factors appearing to influence the learning of pitch. Once identified, each factor can then be evaluated by controlled experiment before confirming its influence. Since it is \'lhat is heard and perceived that is learnt, I have started with the process of Hearing and Perceiving, for as Arnold Abramovitz, Senior Lecturer in Psychology at Cape Town says, "the reception, processing and interpretation of acoustic symbols constitutes some of the most elusive and complex phenomena to attempt to examine, gauge and measure, due partly to the transient, ephemeral nature of sound itself."
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