The spectrographic determination of trace elements in citrus leaves
- Authors: Brandt, Peter Jürgen
- Date: 1962
- Subjects: Citrus , Trace elements in plant nutrition
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4516 , http://hdl.handle.net/10962/d1013552
- Description: From Introduction: With the rapidly growing knowledge on trace elements and their influence on plant nutrition the need for accurate and rapid methods for their determination arose. The essential plant nutrients are usually divided into two groups. The major or macronutrient elements, necessary in comparatively large amounts, and the trace or micro-nutrient elements. In the case of plants, the first group includes Sulphur, Phosphorus, Potassium, Magnesium, Calcium and Nitrogen. The essential trace elements are Iron, manganese, Boron, Copper, Zinc, Molybdenum and Chlorine. Cobalt is essential for animal nutrition as a constituent of Vitamin B₁₂, but its essentiality for plants has not yet been proved. The latter group consists of metals which are catalysts in enzyme reactions and whose presence in the plant in minute amount determines whether the plant will be able to complete the vegetative or reproductive stage of its life cycle. Molybdenum may be quoted as an example of an essential trace element. It is generally recognised to be the catalyst responsible for the fixation of Nitrogen.
- Full Text:
- Date Issued: 1962
A comparative kinetic study of the reaction between chromium nitrate solutions and the carboxyl groups of acetate and collage
- Authors: Russell, Allan Edward
- Date: 1962
- Subjects: Chemical kinetics , Chromium , Spectrophotometry , Electrophoresis
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4493 , http://hdl.handle.net/10962/d1013101
- Description: The kinetics of the coordination reaction between the carboxyl group of the acetate radical and the trivalent chromium ion has been examined by independent methods at a temperature selected to yield reasonably accurate rate data. The study has been extended to an examination of the rate of chromium "fixation" by the carboxyl groups of hide collagen in a series of miniature tannages carried out under similar conditions for comparative purposes. The effect of olation of the chromium ions in solution on the kinetics of t he coordination reaction has also been examined. The rate of coordination of the acetate radical was followed by solvent extraction and spectrophotometric techniques over a range of concentration and pH levels. The rate data revealed a reaction having typical mass-action characteristics, the rate of reaction depending on the concentration levels of the chromium ion and the ionised acetate radical. An attempt made to distinguish a differential reaction rate in the case of a parallel reaction series using boiled and aged chromium nitrate reactant solutions, failed to reveal any significant differences between the series. The reactant solutions gave absorption spectra characteristic of the trivalent chromium ion with maxima in the 420 mµ and 570 mµ wavelength regions. The changes in optical density occurring in the vicinity of the maxima were followed spectrophotometrically, the height of the 570 mµ being found to increase during the course of reaction, while the height of the 420 mµ peak decreased. The variation in optical density at the 570 mµ peak was found to be directly related to the increase in concentration of the product complex in solution in accordance with the Baer-Bougher law, while the decrease in the height of the 420 mµ peak was related to the properties of unolated OH groups associated with the chromium complex as governed by pH and olation changes during the course of reaction. Boiled and aged chromium nitrate solutions gave reactant solutions having initial optical densities greater than those of the correspending fresh reactant solutions at the 570 mµ peak, and less than those of the fresh solutions at the 420 mµ peak. During the course of reaction, however, the two series converged to the same values. The equilibrium reaction solutions were subjected to paper electrophoretic study which indicated that all tho chromium was present in the form of cationic species. This finding was in accordance with stoicheiometric indications in the solvent extraction studies where coordination in a l : 1 ratio was reflected, giving rise to positively charged complex ions only. Making due allowance for band spreading the numbers of species predicted from the kinetic studies correspond with the electrophoretic patterns found. Application of the classical second order kinetic expression to the solvent extraction rate data, yielded plots having two distinctly linear sections, apparently indicating consecutive second order processes occurring in solution, contrary to the findings of previous workers who assign a first order mechanism to the reaction. This finding was consistent with the view that in the case of both the fresh and aged series, reaction consisted of successive coordination of an acetate radical to each chromium atom of a diol complex. Second order rate "constants" were calculated for each step and their dependency on pH level demonstrated. The findings of Hamm et al that these were first order reactions independent of acetate co'ncentration are believed to be due to their use of a large excess of acetate in their experiments. The kinetic study was further extended to an examination of the rate of "fixation"of trivalent chromium by the carboxyl groups of hide collagen under comparable conditions in a series of miniaturv tanning experiments in which the tannage substrate was provided in each of two physical forms:- (a) As hide powder where surface development was large, and (b) as prepared pelt pieces in which the fibrous weave pattern was retained. In view of the heterogeneity of the tannage systems, remarkable similarity was observed in the reaction course when compared with that of the acetate coordination studies, particularly in the case of the hide powder tannages. The dependency of the tannage rate data upon concentration and pH conditions was also found to be the same as in the case of the pure chemical system. The exact correlation between the rate data for the tannage and pure chemical systems was demonstrated by means of correlation plots. Close correlation was revealed in the case of hide powder tannage while the smaller degree of correlation observed in the case of the pelt tannage systems was attributed to the modifying effects of diffusion, particularly on the initial reaction velocity. The effect of using boiled and aged chromium solutions in the tannages was to increase the initial rate of chroniill!l "fixation" apparently due to tho coordination of a dial species at each coordination site. After the initial reaction period, the two series showed a tendency to converge as in the case of the spectrophotometric studies on the acetate reaction. The convergence trend was regarded as indicative of the tendency for the chromium in fresh solutions to under go rapid olation to the ame level as in the boiled and aged solutions. The experimental observations made on the various systems lead to the following conclusions:- (a) The mechanism of coordination of the acetate radical ttrivalent chromium appears to involve the successive coordination of ligand to each of the chromium atoms of a diol complex, both coordination steps proceeding by second order reaction mechanisms. (b) At the pH levels at which the reaction is carried out, the formation of elated bodios is rapid so that reaction in the case of both fresh and aged solutions essentially occurs between an elated species and the ionised acetate radical. (c) Modificati0ns in the absorption spectrum of the reactant solution at the 570 mµ peak are directly related to coordination, while changes at the 420 mµ peak are related to the formation of loosely-bound hydroxo chromium compounds, the concentrations of which depend on the pH level. (d) The mechanism of chromium fixation in hide is essentially similar to that operating in the case of coordination of the acetate radical to chromium, involving attachment of chromium to the side chain acid r sidues of collagen. (e ) The effect of olation is to enhance the rate of chromium fixation by hide protein during the initial reaction stages and to render possible bridge formation between adjacent side chains by secondary coordination during the latter reaction stages. (f) Where pelt pieces are used instead of hide powder, the initial rate of chromium fixation is dominated by the rate of diffusion of chromium into the fibrous structure. It should be stressed that the observations made on the various reaction systems cannot be regarded as exhaustive and the conclusions are subject to further confirmation. Consequently, the present study is essentially of a preliminary nature, but it is felt that the need for further investigation along similar lines has been demonstrated.
- Full Text:
- Date Issued: 1962
The dining end of the kitchen, December 1962
- Date: 1962
- Subjects: Butler, Guy, 1918-2001 -- Photographs Butler family -- Photographs
- Type: Image
- Identifier: http://hdl.handle.net/10962/41327 , vital:25079 , This image is held at the Cory Library for Humanities Research at Rhodes University. For further information contact cory@ru.ac.za. The digitisation of this image was made possible through a generous grant received from the Andrew W. Mellon Foundation 2014-2017. , PIC/M 4943/9.11
- Full Text: false
- Date Issued: 1962
Kei Road 3227DA
- Authors: Trigonometrical Survey (South Africa)
- Date: 1962
- Subjects: 1 : 50000 30.5595° S, 22.9375° E , Kei Road (South Africa) Maps , South Africa History 1910-1961 Maps
- Language: English
- Type: maps , digital maps , cartographic
- Identifier: http://hdl.handle.net/10962/109858 , vital:33197 , Cory Library for Humanities Research, Rhodes University Library, Grahamstown, South Africa , MP476
- Description: 3327 DA Kei Road, South Africa 1:50000 sheet, first edition. Air photography 1953, surveyed in 1960, drawn in 1962 by the Trigonometric Survey Office. T.S.O. 200/1635. (Lugfotografie 1953, opgemeet in 1960, en geteken in 1962 deur die Driehokesmatings Kantoor.) , 1st edition
- Full Text: false
- Date Issued: 1962
Kilnerton Training Institution - Academic Procession, 1962
- Date: 1962
- Subjects: Kilnerton Training Institution -- Photographs Kilnerton Training Institution -- History -- Photographs Pretoria -- History -- Photographs Weaving Park, Pretoria -- History
- Type: Image
- Identifier: http://hdl.handle.net/10962/10851 , vital:21637 , PIC/M 5784
- Description: The Kilnerton Training Institution, affiliated to the Methodist Church of Southern Africa, was established in 1886 in the small suburb of Weaving Park, Pretoria. The Institution was named after Rev. John Kilner, who encouraged the formation of an indigenous clergy in South Africa. The mission of the Institution was to provide seminary education to locals in preparation for ordination. In and above providing seminary education, Kilnerton also served as a primary and secondary school for children in the local community. The Institution is known for some of its illustrious past students, including Dikgang Moseneke (Deputy Chief Justice), Sefako Makgatho, Miriam Makeba, Lillian Ngoyi and Thomas Masekela. , This image is held at the Cory Library for Humanities Research at Rhodes University. For further information contact cory@ru.ac.za. The digitisation of this image was made possible through a generous grant received from the Andrew W. Mellon Foundation 2014-2017.
- Full Text: false
- Date Issued: 1962
Sitting around the dining table, December 1962
- Date: 1962
- Subjects: Butler, Guy, 1918-2001 -- Photographs Butler family -- Photographs
- Type: Image
- Identifier: http://hdl.handle.net/10962/41303 , vital:25076 , This image is held at the Cory Library for Humanities Research at Rhodes University. For further information contact cory@ru.ac.za. The digitisation of this image was made possible through a generous grant received from the Andrew W. Mellon Foundation 2014-2017. , PIC/M 4943/9.8
- Full Text: false
- Date Issued: 1962
Komga 3227DB
- Authors: Trigonometrical Survey (South Africa)
- Date: 1962
- Subjects: 1 : 50000 30.5595° S, 22.9375° E , Komga (South Africa) Maps , South Africa History 1910-1961 Maps
- Language: English
- Type: maps , digital maps , cartographic
- Identifier: http://hdl.handle.net/10962/109697 , vital:33179 , Cory Library for Humanities Research, Rhodes University Library, Grahamstown, South Africa , MP475
- Description: 3227 DB Komga, South Africa 1:50000 sheet, first edition. Air photography 1953, surveyed in 1960, drawn in 1962 by the Trigonometric Survey Office. T.S.O. 200/1620. (Lugfotografie 1953, opgemeet in 1960, en geteken in 1962 deur die Driehokesmatings Kantoor.) , 1st edition
- Full Text: false
- Date Issued: 1962
Salix mucronata - Cape Willow
- Authors: Skead, C J (Cuthbert John)
- Date: 1962
- Subjects: Salix mucronata - South Africa -- Photographs , Trees -- South Africa -- Photographs
- Language: English
- Type: mixed material , photographs , landscape photographs
- Identifier: http://hdl.handle.net/10962/118249 , vital:34613
- Description: Caption "Cape Willows on the banks of Buffalo River a few km north of King Williams Town. 1962.”
- Full Text: false
- Date Issued: 1962
Sand-dwelling eels of the Western Indian Ocean and the Red Sea
- Authors: Smith, J.L.B. (James Leonard Brierley), 1897-1968
- Date: 1962
- Subjects: Fishes -- Classification , Fishes -- Indian Ocean , Fishes -- Red Sea
- Language: English
- Type: Text
- Identifier: vital:14992 , http://hdl.handle.net/10962/d1019664 , Ichthyological Bulletin; No. 24
- Description: The Western Indian Ocean has been found to be notably rich in marine eels. The Moray eels have been treated earlier (Bulletin No 23). In the present revision are described eels of the families OPHICHTHIDAE, ECHELIDAE, M ORING UIDAE, and NEENCHELIDAE, which are chiefly sand-dwelling forms, norm ally not free swimming by day. Some favour muddy areas where the water is turbid, and are found in estuaries, sometimes in or near fresh water. None of these eels are of any economic importance in the Western Indian Ocean though some are eaten by the natives in parts of the region. Only few attain any size, the majority are small and seldom encountered by the ordinary fisherman, in many cases they have been unknown to the local inhabitants. Our specimens were obtained chiefly by rotenone poisoning of suitable areas, mainly intertidal. , Rhodes University Libraries (Digitisation)
- Full Text:
- Date Issued: 1962
Plan of Graham's Town
- Authors: Lewcock, E
- Date: 1962
- Subjects: Grahamstown (South Africa) -- Maps Maps , Streets -- South Africa -- Maps Maps , South Africa
- Language: English
- Type: cartographic , map
- Identifier: http://hdl.handle.net/10962/57798 , vital:26990 , Cory Library for Humanities Research, Rhodes University Library, Grahamstown, South Africa MP485 , MP485
- Description: "Plan probably drawn 1824. Copied by E. Lewcock, Sept. 1962. Original in Albany Museum, Courtesy Surveyor-General."
- Full Text: false
- Date Issued: 1962
A theoretical investigation of the effects of solar eclipses on the ionosphere
- Authors: Walker, Anthony David Mortimer
- Date: 1962
- Subjects: Solar eclipses , Ionosphere , Solar activity
- Language: English
- Type: Thesis , MSc , Masters
- Identifier: vital:5550 , http://hdl.handle.net/10962/d1013467
- Description: The behaviour of the ionosphere during a solar eclipse is of great interest because radiation from the sun is the cause of ionization in the upper atmosphere and it is useful to be able to conduct experiments where this radiation is cut off and restored in a known manner. Experimental results, especially those dealing with the F2 layer, have proved puzzling. Cusps which cannot be explained appear on the records obtained from ionosphere sounders and in the F2 region the electron density at a given height shows a maximum after the eclipse where one would expect it simply to rise to a steady value. An attempt is made in this thesis to explain some of the anomalies in terms of tilts in the ionospheric layers and minima of electron density or "valleys" between the ionospheric layers. The problem is attacked theoretically. Part I deals with the theoretical background to ionospheric physics in general and to this problem in particular. Standard methods of dealing with radio propagation in the ionosphere as well as some methods developed by the author are discussed. Part II deals directly with the effects of a solar eclipse on a theoretical ionosphere. Ionograms which would be obtained in the theoretical ionosphere are constructed. These are scaled by standard methods to show where errors may arise . It appears that tilts in the layers have only a small effect. The effect of the valley is, however, extremely important, giving rise to the apparent maximum of electron density in the F2 layer at a given height after the eclipse. This maximum does not in fact exist but arises from an error in the scaling method which ignores the possibility of a valley. Some records taken during the solar eclipse of 25 December, 1954 have been scaled. They support the conclusion reached theoretically.
- Full Text:
- Date Issued: 1962
Guibourtacacidin: a new Leuco-anthocyanidin from Rhodesian copalwood; (Guibourtia coleosperma)
- Authors: De Bruyn, Guustaaf Cornelis
- Date: 1962
- Subjects: Phanerogams , Angiosperms , Flavonoids , Anthocyanidins
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4459 , http://hdl.handle.net/10962/d1011043
- Description: A new leuco-anthocyanidin, (+)-7,4'dihydroxyflavan- 3:4-diol has been isolated from the heartwood of Guibourtia coleosperma. The heartwood extractives were fractionated by enrichment procedures involving fractional precipitation and Craig partitioning, to give a high RF (subscript) low molecular weight fraction containing the above leuco -anthocyanidin. This was further fractionated by "preparative" paper chromatography . The leuco-anthocyanidin was amorphous and present in low proportion (0.004%) in the wood. On boiling with alcoholic hydrochloric acid the compound gave an anthocyanidin which was identified as 3,7,4'-trihydroxyflavylium chloride. The degradation products formed by alkali fusion, on a micro-scale, were resorcinol and ♭-resorcylic acid, and also p (underscore)-hydroxybenzoic acid. This indicated resorcinol and phenol A and B nuclei respectively. The formation of amorphous dimethyl ether and tetra-acetoxy derivatives indicated two phenolic and two alcoholic hydroxyl groups. The above indicates that the compound was 7,4'-dihydroxyflavan- 3:4- diol and a molecular weight estimation showed it to be monomeric. Comparison of the infrared absorption spectra of the natural dimethyl ether with synthetic (±) dimethoxyflavan- 3:4-diol, to which a tentative 2:3- trans- 3:4-cis conformation had been assigned (Phatak and Kulkarni 94), showed close identity. Crystalline (±)-7, 4 '-dihydroxyflavan- 3:4 - diol was synthesised by catalytic hydrogenation over platinum oxide of the corresponoing (±) -7,4'-dihydroxyflavanonol. The flavanonol was synthesised by sodium hyposulphite reduction of the 7,4 ' -dihydroxyflavonol. The infrared absorption spectra of the natural and synthetic diols were similar but not identical. Chromatographic evidence showed the apparent identity of the synthetic and natural flavan- 3:4- diols, and two possible configurations were assigned for the natural flavan-3:4-diol. The new leuco-anthocyanidin was observed to form an O(underscore)-ethyl ether derivative on manipulation in ethanol. A monomeric leuco- fisetinidin from the heartwood was identified, by two dimensional paper chromatography, as (+) - mollisacacidin. The condensed tannins found also in the heartwood of G.(underscore)- coleosperma appear to be polymeric forms of leuco - fisetinidin and leuco - guibourtinidin. These polymeric tannins form a large proportion of the heartwood extractives and furnish high yields of fisetinidin and guibourtinidin chlorides on boiling with alcoholic hydrochloric acid. Examination of some other members of the Guibourtia spp . by paper chromatography showed that only G (underscore). coleosperma contained the new leuco - anthocyanidin as well as a leuco - fisetinidin. G. (underscore) tessmannii and G. (underscore) demeusii heartwoods contained only leuco-fisetinidin and the related polymers and a close chemical relationship to G.(underscore) coleosperma is thus apparent. G.(underscore) arnoldiana on the other hand is not chemically interrelated with the above members since it appeared to contain only leuco - cyanidin. (±) - 7,4 ' -Dihydroxyflavan- 4-ol was synthesised by hydrogenation of the corresponding flavanone over platinum oxide. Observations were made regarding its reddenig and ease of condensation.
- Full Text:
- Date Issued: 1962
Bush recession - Dubu Drift, Keiskamma River
- Authors: Skead, C J (Cuthbert John)
- Date: 1962
- Subjects: Dubu Drift, Keiskamma River, King Williams Town district (South Africa) -- Photographs , Trees -- South Africa -- Photographs , Deforestation -- South Africa -- King William's Town -- Photographs
- Language: English
- Type: mixed material , photographs , landscape photographs
- Identifier: http://hdl.handle.net/10962/65659 , vital:28824
- Description: Caption "Lone Scotia species tree left standing when all other bush destroyed above Dubu Drift, on the Keiskamma R. southern King William’s Town district. Even the veld is destroyed. Ca. 1962"
- Full Text: false
- Date Issued: 1962
Pharmacy - yesterday to-day and to-morrow
- Authors: Price, C H
- Date: 1962
- Subjects: Pharmacy -- History , Pharmacy -- South Africa -- History
- Language: English
- Type: Text
- Identifier: vital:569 , http://hdl.handle.net/10962/d1004349
- Full Text:
- Date Issued: 1962
Ming, 3 December 1962
- Date: 1962
- Subjects: Butler, Guy, 1918-2001 -- Photographs Butler family -- Photographs
- Type: Image
- Identifier: http://hdl.handle.net/10962/41282 , vital:25074 , This image is held at the Cory Library for Humanities Research at Rhodes University. For further information contact cory@ru.ac.za. The digitisation of this image was made possible through a generous grant received from the Andrew W. Mellon Foundation 2014-2017. , PIC/M 4943/9.7
- Full Text: false
- Date Issued: 1962
Studies on the effects of microclimates on the distribution of larval ticks in the Eastern Cape Province
- Authors: Kraft, Mary Kay
- Date: 1962
- Subjects: Ticks -- South Africa -- Eastern Cape , Ticks -- Ecology -- South Africa -- Eastern Cape , Ticks -- South Africa -- Eastern Cape -- Geographical distribution , Ticks -- Control -- South Africa -- Eastern Cape , Ixodidae -- South Africa -- Eastern Cape , Microclimatology -- Research -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5898 , http://hdl.handle.net/10962/d1013469
- Description: 1. In studying the effects of micro-climates on the distribution of larval ticks in the Eastern Cape Province four species were considered, namely, Boophilus decoloratus (Koch), Rhipicephalus evertsi (Neu), Amblyomma hebraeum (Koch) and Ixodes pilosus (Koch). 2. Three types of investigation were made:- i) autumn and spring surveys of the distribution of larval clusters, which were assumed to be close to positions in which egg-masses had been laid. - (Four species); ii) observations on the survival and development of eggs and engorged female ticks in microclimatically distinct field plots. - (Four species); iii) observations on the behaviour of the larvae and of the engorged female ticks. - (B. decoloratus). 3. The survey and plot data suggest that in autumn larval clusters of I. pilosus were to be found only in well-shaded situations because more exposed places were micro-climatically unfavourable to the survival of earlier stages. 4. The surveys show that in spring 1957 larval clusters of I. pilosus were to be found in unshaded, as well as in shaded, situations. 5. The survey and plot data indicate that the winter of 1957 was not favourable to the development of larvae of B. decoloratus, and that in spring new larval clusters may be expected to appear first in the warmest situations and later in the generally cooler places. 6. The plot data show that during hot and dry periods exposed situations were unfavourable to tho engorged females and eggs of all four species considered, but that during such periods these stages could sometimes survive in well-shaded places. 7. The survey and plot data show that in autumn and in spring larval clusters of B. decoloratus and R. evertsi may be present in unshaded situations. 8. The plot investigations provide little information about the distribution of larval clusters of A. hebraeum, but the survey data suggest that it is not remarkably different from that of B. decaloratus and R. evertsi. 9. There is a discrepancy in the survey and plot data: the surveys show that larval clusters of R. evertsi, and B. decoloratus were rare or absent from well-shaded situations, whereas tho plot data suggest such situations were micro-climatically favourable to larval developmcnt during the months preceding Autumn. 10. The observations on the behaviour of larvae and engorged females of B. decoloratus provide information which suggests that the behaviour of those stages may account for the rarity of larval clusters in well-shaded places. 11. The relative density of larval clusters of B. decoloratus is evidently also affected by factors other than micro-climate . The dropping- off behaviour of engorged female ticks appears to be possibly important in this.
- Full Text:
- Date Issued: 1962
A study of South African aquatic Hyphomycetes
- Authors: Greathead, Sarah Kathleen
- Date: 1962
- Subjects: Hyphomycetes -- South Africa , Aquatic fungi -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4269 , http://hdl.handle.net/10962/d1014992
- Description: 1, Eighteen species of aquatic Hyphomycetes are recorded from South Africa for the first time. All except two of these can be assigned to described species. The other two are new species of Articulospora and Anguillospora and are described in this thesis. Three unidentified spore types, an "Articulospora" type and "Anguillospora" type and a Y-shaped spore are also described. 2. Spore development in ten species is described. 3. A key to the fungi described in this thesis is given. 4. General notes on the ecology of these fungi and a table recording the fungi found in the Eastern Cape Province of South Africa, their distribution within the localities and the nature of the material on which they are growing are given. 5. The gross characteristics of plate cultures of six species, five growing on malt agar, Czapek agar, plain agar and maize agar and one on malt agar only are described. 6. Growth of four species in liquid culture using the Czapek-Dox medium is reported. 7. The results of an investigation into the effect of variations in temperature and medium on the growth of plate cultures of five species are analysed, discussed and conclusions are drawn. 8. Growth of certain isolates of four species on twigs is described.
- Full Text:
- Date Issued: 1962
Fishes of the family Gaterinidae of the Western Indian Ocean and the Red Sea with a resume of all known Indo Pacific species
- Authors: Smith, J.L.B. (James Leonard Brierley), 1897-1968
- Date: 1962
- Subjects: Grunts (FIshes) , Fishes -- Classification , Fishes -- Indian Ocean , Fishes -- Red Sea
- Language: English
- Type: Text
- Identifier: vital:14993 , http://hdl.handle.net/10962/d1019670 , Ichthyological Bulletin; No. 25
- Description: Family Gaterinidae - Fairly robust usually deeply ovoid body, moderately compressed, covered with moderate to small strong adherent ctenoid scales, mostly only front of muzzle naked. Vertical fins partly scaly. Lateral line complete, concurrent with dorsal profile, but in adults not very distinct, tubules oblique, fewer than series of scales. Snout not pointed, moderately to markedly blunt. Mouth moderate, little protractile, maxilla slips below preorbital for most of its length. Lips well developed, often greatly swollen with age. Feeble cardiform teeth in bands in each jaw, outer series often enlarged, no teeth on palate or tongue. Chin with distinct pores, no central groove behind symphysis. Preopercle coarsely serrate in young, finer w ith age, obsolescent in very large fishes. Gill membranes free from isthmus. Gillrakers well developed, stout, spiny behind, 20-40 on whole outer arch. Dorsal continuous, of (9)10-14 spines and 15-26 rays, total 27-35, spines well developed, moderate to powerful, fewer than soft rays, but spinous part mostly with longer base, fin of almost uniform height to deeply notched, usually less so with age. Anal short, height exceeds base, III (6)7-8(9), 2nd spine mostly longer and stouter than 3rd. Caudal rounded in juveniles, feebly emarginate or truncate with age. Pectoral distinctly shorter than head. Juveniles up to about 40mm differ from the adults in certain features. They show some Pomadasyid characters i.a. the lateral line is continuous, the tubular scales adjacent; no pores are visible on the chin and the maxilla reaches to below the eye. Also the predorsal scaling ends in mid interorbital, and the scale rows above the lateral line are fewer. With growth the scale rows increase in number, but not the tubular L .l. scales, which become separated, the predorsal scales extend to the nostrils, while the snout extends, the maxilla not reaching to eye. , Rhodes University Libraries (Digitisation)
- Full Text:
- Date Issued: 1962
An investigation into the effects of ant control on scale insect populations (Homoptera, Coccoidea) of citrus trees in the Eastern Cape Province, South Africa
- Authors: Brettell, J H
- Date: 1962
- Subjects: Scale insects -- South Africa Insect pests -- Biological control
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5838 , http://hdl.handle.net/10962/d1009700
- Description: In order that the citrus industry in South Africa may be commercially developed to the greatest possible extent it is of importance that certain basic ecological problems should be investigated. Until the complex relationships between the host plant, the insect pests and their parasites and predators are known, the results of applications of either chemical or biological control must be largely a matter of chance. A certain amount of rather generalised work in this connection has already been done in South Africa, principally by Carnegie (1955), Smithers (1953) and Whitehead (1948) in the Eastern Cape Province and by Steyn (1954) in the Transvaal. The first three of these workers were content to determine which species of insects occurred in citrus orchards and made some attempts to study the biology of certain predators. Steyn went a little further when he correlated ant activity with scale insect infestations. Without doubt the most economically important insect pests of citrus are the scale insects (Homoptera: Coccoidea). Introduction, p. 1.
- Full Text:
- Date Issued: 1962
Death, immortality & the biblical doctrine of resurrection : a study in the theology of renewal
- Authors: Bank, Louis
- Date: 1962
- Subjects: Jesus Christ -- Resurrection , Resurrection -- Biblical teaching , Church renewal
- Language: English
- Type: Thesis , Bachelor , BDiv
- Identifier: vital:1280 , http://hdl.handle.net/10962/d1013448
- Description: From Introduction: The fact of the resurrection of Jesus Christ, the Son of God, from the dead is the central fact of Christian faith and teaching. This centrality is certainly accorded it in the Bible, but has often been forgotten in the thinking, practice and worship of the Christian Church. (The paucity of available contemporary literature on the subject is one fact which may serve to illustrate this.) The subject of the first Christian sermon preached on the Day of Pentecost was on the Resurrection. The Jesus whom they had crucified, God had made both Lord and Christ. (Acts 2. 37.) The Gospels would belie their name if they had left us with an account of the life and tragic death of a man who claimed to know and reveal God in a special way. The news is good news precisely because of the Resurrection of our Lord from the dead.
- Full Text:
- Date Issued: 1962