List of Titles

Problems of species definition in Lake Malawi cichlid fishes (Pisces: Cichlidae)

- Lewis, Digby S C, J.L.B. Smith Institute of Ichthyology

Authors: Lewis, Digby S C , J.L.B. Smith Institute of Ichthyology
Date: 1982-09
Subjects: Cichlids -- Nyasa, Lake , Fishes
Language: English
Type: text , book
Identifier: http://hdl.handle.net/10962/69918 , vital:29595 , Margaret Smith Library (South African Institute for Aquatic Biodiversity (SAIAB)) Periodicals Margaret Smith Library (South African Institute for Aquatic Biodiversity (SAIAB))
Description: Online version of original print edition of the Special Publication of the J.L.B. Smith Institute of Ichthyology; No. 23 , The evolution of the cichlid species flock in Lake Malawi has taken place very rapidly and resulted in the proliferation of a large number of species many of which are similar to one another. This has given rise to a situation in which traditional methods of distinguishing species based on preserved specimens are often of limited value. There are many instances of different species having almost identical morphologies, of single populations of one species showing considerable morphological variation and of marked geographical intraspecific variation. Polymorphism is considered not to be as widespread as previously thought, and pronounced random intraspecific colour variation within a population is discounted. Sympatric sibling species may be distinguished by observing behavioural and habitat differences in the field, but no means has been devised for ascertaining whether morphologically and behaviourally similar allopatric forms are specifically distinct. Lack of access to fresh specimens and lack of information on distribution and habitat have resulted in numerous errors appearing in taxonomic works on Lake Malawi cichlids. Great care is needed when attempting scientific descriptions of cichlid species from the African Great Lakes, and it is suggested that such work be left to specialists with knowledge of living and fresh fish in these lakes.
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Date Issued: 1982-09

Plotonus nkunga, a new species of catfish from South Africa, with a redescription of Plotosus limbatus Valenciennes and key to the species of Plotosus (Siluriformes: Plotosidae)

- Gomon, Janet R, Taylor, William Ralph, J.L.B. Smith Institute of Ichthyology

Authors: Gomon, Janet R , Taylor, William Ralph , J.L.B. Smith Institute of Ichthyology
Date: 1982-08
Subjects: Catfishes
Language: English
Type: text , book
Identifier: http://hdl.handle.net/10962/69871 , vital:29590 , Margaret Smith Library (South African Institute for Aquatic Biodiversity (SAIAB)) Periodicals Margaret Smith Library (South African Institute for Aquatic Biodiversity (SAIAB))
Description: Online version of original print edition of the Special Publication of the J.L.B. Smith Institute of Ichthyology; No. 22 , Plotosus nkunga sp. n., from the east coast of South Africa, possibly ranging as far north as Zanzibar, is most similar to Plotosus limbatus Valenciennes, from the coasts of India, Sri Lanka, Kenya and Aldabra. Plotosus nkunga differs most notably in having fewer total gill rakers on the anterior faces of the first two arches, 16 to 21 versus 20 to 25 first arch, 16 to 24 versus 23 to 27 second arch; in having modally one more precaudal vertebra and slight modal differences in number of ribs and branchiostegal rays; in the shapes of the mesethmoid and the parapophyses of the fourth and fifth centra of the anterior complex vertebra; in the length of the maxilla; and in certain body proportions. Descriptions, annotated synonymies and illustrations are given for both species. A key to the five known species of Plotosus is presented.
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Date Issued: 1982-08

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Simochromis margaretae, a new species of cichlid fish from Lake Tanganyika

- Axelrod, G S (Glen S.), Harrison, J A (James A.), Rhodes University. J.L.B. Smith Institute of Ichthyology

Authors: Axelrod, G S (Glen S.) , Harrison, J A (James A.) , Rhodes University. J.L.B. Smith Institute of Ichthyology
Date: 1978-12
Subjects: Simochromis margaretae , Simochromis -- Classification , Fishes -- Classification , Fishes -- Tanganyika, Lake
Language: English
Type: text , book
Identifier: http://hdl.handle.net/10962/69825 , vital:29585 , Margaret Smith Library (South African Institute for Aquatic Biodiversity (SAIAB)) Periodicals Margaret Smith Library (South African Institute for Aquatic Biodiversity (SAIAB))
Description: Online version of original print edition of the Special Publication of the J.L.B. Smith Institute of Ichthyology; No. 19 , A new cichlid species of the endemic Lake Tanganyikan genus Simochromis is described from four specimens from Kigoma Harbour, illustrated and compared with the other five species of the genus. The new species, S. margaretae, differs from the others in having a greater caudal peduncle depth, longer anal fin spines, and a narrower mouth. The new species further differs from its closest relative, S. marginatus, in having a greater interorbital width, greater postocular head portion, longer mouth, and shorter pectoral fin.
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Date Issued: 1978-12

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Ultra-high precision manufacturing

- Abou-El-Hossein, Khaled

Authors: Abou-El-Hossein, Khaled
Subjects: Machining , Diamond turning , f-sa
Language: English
Type: text , Lectures
Identifier: http://hdl.handle.net/10948/20878 , vital:29410
Description: One of the engineering areas focusing on the research and development of highvalue components and manufacturing technologies is precision engineering. Precision engineering represents a variety of engineering and science disciplines ranging from areas such as mechanical, electronics and industrial engineering to chemistry, physics, optics and materials science. This paper aims at familiarising the reader with the recent advances in ultra-high precision manufacturing technologies and their applications for the production of various critical components employed in different sectors of the industry. In this paper, the principles of ultra-high precision manufacturing will be discussed followed by examples of its use in various industrial applications. The status of ultra-high precision manufacturing in terms of current research issues and future trends will be discussed. In addition, research activities and projects in the area of precision manufacturing that are currently conducted at the NMMU will be also highlighted. Finally, the author looks forward to presenting herewith comprehensive information that could be useful to the reader and easy to understand by the bigger NMMU’s community.
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Writing official letters

- International Confederation of Free Trade Unions (ICFTU)

Authors: International Confederation of Free Trade Unions (ICFTU)
Subjects: ICFTU
Language: English
Type: text
Identifier: http://hdl.handle.net/10962/162021 , vital:40748
Description: To most of us, speech comes more readily than writing, and when information has to be passed on, the obvious way of doing it is by word of mouth. The telephone has greatly widened the opportunity of conducting business in this way. But a trade unionist is well advised not to rely on this method alone. In the affairs of the heart, it may be good advice never to put anything in writing. The reverse is often true in business. What is written, especially if carbon copies are kept, survives as a record. The record remains as a reminder of what has happened, and a check in the event of a dispute. It is only too easy during transactions which may take some months, to forget exactly what had happened at any one time. Written records will provide exact information, not only about what happened but — what is often as important — when it happened. When it is remembered that the actions of shop stewards and branch officers may be vital evidence in a Court of Law, as for example in the pursuit of claims for damages on behalf of union members, exact records are extremely important. For this reason, a duplicate copy of letters provides branch officials with lasting evidence of their own communications. All branch letters, therefore, should be written in duplicate. If letters are typed or written in an interleaved correspondence book, it is easy to make carbon copies. But even if letters are hand written on loose sheets, ordinary carbon paper will make clear copies providing a fountain pen with a fairly hard nib or a bail-point pen is used.
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