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Research in Action South African Journal of Science 99, May/June 2003 201

locations which show various stages of The vegetation of the habitat of the disturbance and succession. Data were also available from studies on Goukamma Brenton blue , Nature Reserve.3 Relevés (5×5m)were sampled and Braun Blanquet cover/abun- niobe (Trimen), in the , dance and site characteristics recorded. These data were analysed using TWIN- SPAN to classify the sites and reciprocal averaging to show their relationships.4 The habitat of the Brenton blue butter- a* b c R.A. Lubke , David Hoare , Janine Victor and fly (Fig. 3) was studied within the fynbos Robert Ketelaard to determine the ’s plant preferences. The butterfly lays its eggs on the under- side of leaves of erecta Thunb., the Brenton blue butterfly weed. The HE BRENTON BLUE BUTTERFLY IS KNOWN Study area specimens of I. erecta on which eggs had only from a small population in one Three localities were investigated, been laid were marked with flags by D. hectare of asteraceous coastal fynbos at T namely, Brenton Extension 1 (where the Britton and L. Silberbauer (pers. comm.) Brenton-on-Sea. This fynbos is characterized O. niobe by a great diversity of shrubs, herbs and only known colony of exists), and vegetation at each of these localities 2 graminoids, with a successional gradient to Nature’s Valley(where O. niobe was found was sampled with 1-m quadrats. Fifteen thicket where Pterocelastrus tricuspidatus is in the past but is now locally extinct), and samples were taken where I. erecta was dominant. The eggs of the butterfly are laid Goukamma Nature Reserve (Fig. 1). The present with eggs and 15 quadrats were on the lower side of the leaves of Indigofera last was included because of the similarity sampled where the plant was without 2 erecta, on which the larvae feed. Fifteen 1-m of the vegetation composition in this eggs. Density, percentage cover, total quadrats containing plants of Indigofera erecta reserve to the two other sites. Other simi- cover and cover of dead or decaying with and without eggs of the butterfly were larities exist as discussed below, making I. erecta were recorded. The data were distinguished and sampled separately from 2 Goukamma Nature Reserve a potential analysed for percentage frequency, mean 15 1-m quadrats containing plants of Indigo- fera erecta without eggs. No marked differ- site for the relocation of the butterfly. density and mean percentage cover for ences in total vegetation, shrub or herb cover Brenton Extension 1 is situated on the each species and an importance value of between the sites with and without eggs were seaward-facing slopes between the west- each species was calculated.5 Density data observed. There was a difference in abun- ern head of the estuary and the for the 30 quadrats were used in an ordi- dance of the fern Pteridium aquilinum, with Buffelsbaai headland (Figs 1 and 2). These nation analysis by reciprocal averaging to over 30% cover at sites with no eggs and only slopes are fairly steep and approach an show the relationship between samples about 6% at sites with eggs present. This could altitude of 200 m above sea level. Nature’s and species.4 reflect the absence of other plants where the ferns had such dense cover. Valley is east of at the mouth of the Grootrivier. The river and its Plant communities Introduction tributaries run through a series of deep A floristic comparison of the vegetation gorges opening to the ocean. The study The Brenton blue butterfly, Orachrysops of the study sites with neighbouring site at Nature’s Valley is situated on an niobe (Trimen), is known only from a 1-ha floras indicated that the dune fynbos of ancient dune system running parallel to plot at Brenton-on-Sea, near Knysna, the Brenton and Nature’s Valley sites is 1 the coast and consisting of sediments very Western Cape province. The habitat of more similar to each other than to dune similar in nature to the Brenton site. the butterfly is surrounded by new housing fynbos at Goukamma Nature Reserve or Goukamma Nature Reserve at Sedgefield development and is also within an area on the slopes between Buffelsbaai and forms part of the dune and lake complex I. erecta which is planned for further develop- Brenton. In addition, has not been of this area. It stretches from Groenvlei in ment. It is therefore important to obtain observed at either Goukamma Nature the west to beyond the Goukamma River information on the status of this species Reserve or Buffelsbaai. A more careful in the east and borders on Buffelsbaai. Indigofera and its habitat to ensure its survival. The search for this species may be The reserve borders on the ocean and objectives of the study reported here necessary to establish its distribution ranges in altitude from 0 to 200 m above were to: collate and synthesize floristic within the vegetation types. sea level. information on the vegetation of the site A mosaic of dune thicket and fynbos is at Brenton-on-Sea, and other potential All three localities are fairly steep, the dominant sea-facing vegetation along areas where the butterfly may occur; in- sea-facing slopes and are likely to be this coastal region (Fig. 3). The dune vestigate the vegetation quantitatively affected by marine processes. It is known thicket occurs on calcareous coastal dunes that salt-laden air and direct salt spray can where annual rainfall exceeds 450 mm, and describe the dynamics of the vegeta- 2 tion; and identify reasons for the selection affect vegetation growth markedly. Local conditions which are favourable at the of the site by the butterfly as its habitat. climatic conditions are ameliorated also localities studied. The fynbos may be by this proximity to the shore-line. asteraceous or grassy, and may be de-

aDepartment of Botany, Rhodes University, Grahamstown scribed as typical mountain fynbos, 6140, South Africa. Methods which at some places is found fairly close bRange and Forage Institute, Private Bag X05, Lynn East 0039, South Africa. The field work at Brenton-on-Sea and to the coast. cNational Botanical Institute, Private Bag X101, Pretoria Nature’s Valley was undertaken in Two main communities were identified 0001, South Africa. December 1996. We sampled the habitat at the Brenton Extension 1 study site, dDutch Butterfly Conservation, P.O. Box 506, 6700 AM Wageningen, The Netherlands. of the butterfly at Brenton, surrounding coastal fynbos and dune thicket. These *Author for correspondence. E-mail: [email protected] areas burnt in the summer of 1995/96, and occurred as a mosaic and resulted in a 202 South African Journal of Science 99, May/June 2003 Research in Action

Fig. 1. Map of the southern Cape, showing the study site localities. local complexity of structure which was of these woody species occur within the mum percentage cover of shrubs, herbs difficult to map (Table 1). fynbos as seedlings or a single individuals and bracken. Table 2 details all of the plant Coastal Fynbos is a variable community and can be considered as pioneer species species found within the sites with and characterized by bracken fern (Pteridium in the transition of fynbos to thicket. without eggs. Indigofera erecta was always aquilinum), Indigofera erecta (Brenton blue Indigofera erecta and other herbaceous present because this was the indicator butterfly weed), Leucadendron salignum, species do not occur under closed thicket. plant where the quadrats were located. Rhynchosia capensis and about ten other Although each I. erecta specimen was species which did not occur consistently. Habitat conditions at egg-laying sites examined for the presence of eggs, some Many of these are members of the Aster- From analysis of the microhabitat could have been overlooked or could aceae family, hence the term asteraceous where the female lays eggs, we deter- have the right potential qualities for eggs coastal fynbos. The fynbos community mined that there is possibly a critical com- but were not used by the female butter- (No. 2, Table 1) identified as the possible plement of species which is attractive to flies. Note that the first ten plant species habitat of the butterfly, had a higher the female butterfly as well as an opti- have a high importance value (>7) in the species richness, with Bobartia aphylla, Myrica quercifolia, Oxalis species, and Wat- sonia pillansii present. A second fynbos community was characterized by the presence of Indigofera verrucosa and Lightfootia fasciculata. A number of species were common to both communities, but generally absent from the dune thicket. Disturbed fynbos communities were identified as burnt areas (samples 2 and 8) and those cleared of woody species (samples 3 and 4). The burnt areas had higher species richness and floristically matched the butterfly-favoured fynbos areas, whereas the cleared areas were species poor and contained mostly pioneer plant species. Indigofera erecta occurred in burnt areas, but not after bush clearing. Dune thicket occurred as clumps within the fynbos at the Brenton Extension 1 site dominated by Pterocelastrus tricuspidatus Fig. 2. Brenton-on-Sea, near Knysna above Buffelsbaai, site of the only known population of the Brenton blue and various other woody species. Many butterfly, Orachrysops niobe. Research in Action South African Journal of Science 99, May/June 2003 203

sub-set of quadrats with eggs on the food plant. By comparison, the great abundance and high importance value of Pteridium aquilinum and the shrub or small tree Pterocelastus tricuspidatus in the set with- out eggs, means that some of the first 10 species have a much lower importance value (<6). It is likely that some of these species are necessary in a habitat for the butterfly to lay eggs. It may appear that the relatively high percentage of shrubs, trees and ferns has a major influence on the site chosen (Table 2). However, this is not necessarily true as the ordination of samples and species shows. The relationships between the quadrats with and without eggs are shown in Fig. 5. There is an almost com- Fig. 3. Profile diagram of the Brenton blue butterfly habitats at Brenton-on-Sea. plete separation of the samples without eggs from those with eggs. A fairly tight been investigated.6 In an examination of case at Nature’s Valley for O. niobe, which cluster of samples with eggs may indicate butterfly diversity along an urban gradi- disappeared there in the 1980s (J. Ball, that the female needs a complement of ent at six sites near Palo Alto, California, pers. comm.). species as a suitable micro-habitat to lay Blair and Launer6 found that species Dune thicket is dominated by bird- eggs. One exception is quadrat 1, which diversity was highest at intermediate dispersed plant species and is not fire- was a disturbed and open habitat, and levels of disturbance, whereas abundance prone. It is associated with deep, rela- separated from the more typical set of decreased from natural to urban areas. tively fertile soils in fire-protected sites at micro-habitats on axis 1 (Fig. 4). Thus disturbance of the habitat is not low altitudes and with a higher propor- necessarily detrimental to butterfly habi- tion of summer rather than winter rain.7 Discussion tats, as we have found in this case. In- Asteraceous and grassy fynbos occurs The effects disturbance due to of urban- creased urban development, however, where there is a high proportion of sum- ization butterfly communities have rarely could lead to loss of species as was the mer rainfall on finer textured and more

Table 1. Abbreviated two-way table of classified samples and the diagnostic species of the plant communities studied at Brenton Extension 1 (samples 1–8) and Nature’s Valley samples (9 and 10).

Fynbos community 1 Fynbos community 2 Thicket community Relevé number: 9 10 12783564

Fynbos community — 1 species Indigofera verrucosa ++ Lightfootia fasciculata ++ 1 1 Fynbos community — 2 species Bobartia aphylla 1+1 Myrica quercifolia 11 Oxalis sp. +++ Watsonia pillansii ++3 General fynbos species Pteridium aquilinum 1 3333 + Indigofera erecta ++ ++++ Leucadendron salignum ++ +++ Metalasia muricata 2b 2a + + + Rhynchosia capensis ++ + 1 Cullumia decurens 1++ Pelargonium capitatum 1++ Fynbos to thicket transitional species Rhus glauca + 1 2b 2a Cineraria sp. ++3+ Stoebe plumosa +++ Helichrysum cymosum +2b2a Helichrysum petiolare ++2b Senecio purpurea 11+ Pterocelastrus tricuspidatus +1+4 Chironia baccifera ++2b General species for all communities Chrysanthemoides monilifera +131 Isolepis cernua +++2a Tetraria cuspidata 1+1 Ficinia ramosissima 13+ Dichisma ciliatum 2a +

A number of general species have been excluded. Numbers and letters in the table represent the Braun-Blanquet scale of cover abundance, namely + = present; 1 = 1–5% cover, etc. Key to localities: 1, Coastal fynbos with thicket invasion; 2, burnt area above township; 3, cleared thicket; 4, pioneer plants on cleared areas; 5, thicket; 6, thicket/bushclump; 7, coastal fynbos — top of hill; 8, burnt area above township; 9 and 10, coastal fynbos. 204 South African Journal of Science 99, May/June 2003 Research in Action (+), Conyza (+), Indigofera verrucosa alaternoides (+), var. Clutia alaternoides 33.5 79.9 25.1 79.9 25.1 16.7 14.7 24.4 (+), Pentaschistis heptamera (+), ) (%) –2 Quadrats without eggs on food plant Cynodon dactylon Ornithogalum graminoides (Plants m (+), (+), fastigata humilis var. subsp. (%) Crassula subulata (+), Knowltontia vesicatoria (+), Pelargonium capitatum Felicia echinata –– 27 20 0.73 1.53 0.33 0.33 4.6 5.8 11 10 (+), (+), quadrats with and without eggs of the Brenton blue butterfly. 2 Helichrysum petiolare sp (+), campestris, Chironia melampyrifolia ) (%) –2 Oxalis subsp. , Cheilanthus viridis, Rubia petiolaris, Maytenus heterophylla, Struthiola hirsuta, Thamnochortus glaber, Kniphofia uvaria. (+), indet. 7– 0.07 – 0.07 – 0.9 – 37 27 27 1.2 1.13 0.4 6.6 0.33 9 3.9 17 Agathosma capensis Quadrats with eggs on food plant 13 0.4 0.2 2.5 26 33 0.47 0.33 4.6 12 2727271320 0.5320 0.3320 0.5320 0.1320 0.26 0.4 0.3313 1.93 0.3313 0.87 0.33 0.13 0.413 1.9313 0.73 4.4 0.413 0.33 5.9 0.33 0.2 5.0 1.7 1.27 0.13 5.1 0.13 3.7 0.13 16 0.13 1.2 3.2 11 14 3.0 0.13 30 4.6 3.0 14 0.2 20 2.5 22 7 3.6 13 24 7 1.7 15 13 5.4 – 1.8 27 7 21 27 0.2 0.13 30 7 0.13 1.07 13 13 29 – – 0.07 0.53 20 0.27 0.4 0.67 20 0.13 0.2 0.13 – 33 0.07 – 0.4 – 0.27 1.4 2.0 1.7 0.13 0.2 0.2 3.9 – 0.4 0.9 27 3 0.6 4.2 32 – 1.1 15 0.33 1.8 40 11.4 14 – 3.2 37 – 31 2.7 16.8 22 – 23 5 9387675347 3.2747 7.3347 1.8740 5.240 1.4 10.2727 1.6 12.8 0.8 6.73 0.93 6.6 1.00 30.7 7.6 0.27 1.2 44.3 7.0 19.9 0.67 0.93 27.4 1.8 17.9 2 10.2 1 15.5 60 7.1 7.6 3 5.6 6 53 8 60 2.13 7 10 9 73 12 100 1.67 20 7.93 1.67 33 – 20 2.6 – 6.87 1.73 13.07 0.6 12.5 0.6 – 0.4 7.47 33.4 10.8 – 38.7 0.47 6 2.53 0.33 – 21.2 7 62.8 2 – 3.8 7.4 4 3.1 1 18 8 21 (%) (Plants m 100 4.0 2.2 22.9 4 100 5,8 4.67 28.1 3 (+), Hibiscus trionum, Asteraceae erinoides Tarchonanthus camphoratus (+), Muraltia ericaefolia, Rhoicissus digitata, Crassula campestris subsp. sp. indet, Grass sp. indet., (+), sp. 13 0.33 1.73 4.3 17 13 0.47 1.2 3.6 19 sp. 13 0.13 0.13 1.7 30 13 0.87 033 3.6 20 . Percentage frequency, mean density and cover and importance value of plants in 1-m canadense, Erica Sporobolus africanus Mean % cover fernsThe following species only occurredEhrharta once or twice (+, calycina quadrats with eggs on food plant): 6.4 Ehrharta villosa Cineraria Diospyros dichrophyllaStoebe plumosaPterocelastrusLobelia tricuspidatus neglectaDichisma ciliatumSenecio purpureasImperata cylindrica Erica copiosaRhus crenataRhus lucida Hypoxis villosaMyrsine africanaLightfootia Centella asiaticaCullumia decurrens Erica speciosaHypericum aethiopicumPeucedamumMetalasia capense muricataAnthospermumLeucadendron aethiopicumAsparagus salignum densiflorusHelichrysum foetidum Indigofera erectaTetraria cuspidataFicinia ramosissimaHelichrysumIsolepis cymosum cernuaPteridium aquilinumRhynchosia capensis Table 2 Species Frequency Mean density Mean cover Importance value Rank Frequency Mean density Mean cover Importance value Rank Mean % total coverMean % dead & detritus coverMean % total coverMean % dead & detritus coverMean % cover shrubsMean % cover herbsMean % cover graminoids 18.5 18.5 75.5 75.5 18.9 36.7 18.6 Research in Action South African Journal of Science 99, May/June 2003 205

The impact of housing on the habitat of the butterfly has also been investigated.1,16 The proximity of houses could result in the extinction of the species. However, suggestions have been made regarding the artificial control of the dynamics of the vegetation in order to maintain a suitable Fig. 4. Classification of the study sites with coastal fynbos. TWINSPAN analysis of available floristic data. microhabitat for the butterfly popula- tion.17 fertile soils than for other fynbos types.7 plant species required, our results (Table 2, Since these factors favour both vegetation Fig. 5) suggest that the butterfly selects I. Management of the habitat types, there is an interaction where the erecta in a habitat with an open structure As a result of these and other studies, vegetation is in transition. and a wide variety of the fynbos, to lay recommendations on the management of Whether fynbos is a successional stage eggs. Furthermore, the density of the the Brenton blue butterfly and its habitat towards thicket has been much debated, I. erecta is fairly similar in quadrats both have been put forward.1 No further hous- with evidence to support this view. with or without eggs, but the cover is ing development has been allowed Pierce8 has shown that thicket seedlings higher in quadrats without eggs (Table 2). within the butterfly’s habitat in Brenton become established from bird-dispersed This suggests that an increased cover of Extension 1. Vegetation management by propagules under emergent fynbos leaves of I. erecta is required if there is a reducing the ferns and shrubs, by selec- shrubs. Fire frequency in relation to rates denser shrub or fern layer. tive burning, has been suggested. The of thicket development are thought to This study implies that in searching for burning programme that was introduced be the main determinants in the relative the ideal habitat for the butterfly, the on the slope above the habitat site was not distributions of fynbos and thicket.9 following plant species should be pres- successful in attracting the butterfly, Under certain conditions moribund ent: Indigofera erecta, Ficina ramosissima, probably because the thicket is too dense fynbos may become extensively invaded Tetraria cuspidata, Isolepis cernua, Heli- there. by woody species, thus affecting vegeta- chrysum cymosum, Pteridium aquilinum, Suggestions for further studies include: tion structure and diversity.3 Erica speciosa, Peucedanum capensis, the identification of similar patches of The ideal fire frequency in coastal Rhynchosia capensis, and Hypericum fynbos with like plant species and trans- fynbos is between 20 and 30 years.11 aethiopicum. Minor species such as other location of to these sites, eco- Thicket formation in the absence of fire legumes may be important as food for the logical studies on the manipulation of the for periods exceeding these limits may be adult butterflies. Plant species richness habitat so that it is favourable for the responsible for incremental degradation may play a part in the selection of habitat. breeding of the butterfly, and more inten- of the fynbos habitat of the butterfly, as Some authors have found that species sive studies of the requirements of the seems to have occurred at Brenton Exten- with a geographically restricted range butterfly and its host plant. A revised sion 1. Over the years this could have led occur in the most species-rich communi- management plan is being drafted by the to a reduction in the butterfly population. ties.12,13 However, Lewis et al.14 found on Brenton blue butterfly management com- Grundel et al. found that canopy cover Grande Comore, off Madagascar, that mittee to obtain funding. had an influence on the habitat use of the endemic butterflies did not show this re- Karmer blue butterfly in oak woodlands lationship. Phenology of the flowering Conclusions 11 of Illinois. species and the use of the plants by both Studies on the present and past habitats adult and larval butterflies can also be an of the Brenton blue butterfly at Brenton- 15 Microhabitats for the Brenton blue aspect requiring further study. Shapiro on-Sea and Nature’s Valley have shown butterfly found that temporal relationships of but- that the butterflies may have very partic- Although it was not possible to define terflies in oak woodlands of Pennsylvania ular habitat requirements. They occur in the microhabitat and complement of was important. mature dune fynbos, which we have called coastal fynbos. Although many of the early colonizers of the dune fynbos are present, such as the Phyllica species, Metalasia muricata and Ehrharta villosa, there are many more species of Ericaceae present, as well as Proteaceae and Astera- ceae. The soils are more mature with a build-up of organic matter and there is an invasion of thicket species such as Ptero- celastrus tricuspidatus, Maytenus hetero- phylla and Rhus species. Rainfall is high in these regions, at least during some peri- ods of the year, with a high sedge (for example, Isolepis cernua and Ficinia ramo- sissima) and graminoid cover. The butter- fly appears to require a specific stage in the coastal fynbos vegetation for breeding sites and fire probably maintains this mo- Fig. 5. Ordination of the 30-m2 quadrats of the Brenton blue butterfly breeding habitat by reciprocal averaging. saic of vegetation types. However, the 206 South African Journal of Science 99, May/June 2003 Research in Action

vegetation is in a dynamic state, and plant diversity in the Goukamma Nature Reserve, (1992). Ecosystem management. In The Ecology of Southern Cape. B.Sc. (Hons) thesis, Rhodes Univer- Fynbos: Nutrients, fire and diversity, ed. R.M. Cowl- should best be maintained with fire, burn- sity, Grahamstown. ing, pp. 345–371. Oxford University Press, Cape ing at intervals of more than 10 years. 4. Gaugh H.G. (1982). Multivariate Analysis in Town. Community Ecology. Cambridge University Press, We thank the Joint Research Committee of Rhodes 11. Grundel R., Pavlovic N.B. and Sulzman C.L. Cambridge. (1998). Habitat use by the endangered Karmer University for financial support; Coastal and Environ- 5. Lubke R.A. (1982). Research Techniques Implemented blue butterfly in oak woodlands: the influences of mental Services for providing financial support and in a Quantitative Survey of the Woody Vegetationof the canopy cover. Biol. Cons. 85, 47–54. Nylsvley Savanna Ecosystem Study Area. FRD facilities for carrying out the study; and Dave Britton, 12. Thomas C.D. and Mallorié H.C. (1985). Rarity, Occasional Report no. 3, Pretoria. Letitia Silberbauer, Jonathan Ball and Dave Edge for species richness and conservation, butterflies of 6. Blair R.B. and Launer A.E. (1997). Butterfly diver- information and assistance on the butterfly locality the Atlas mountains in Morocco. Biol. Cons. 33, sity and human land use: species assemblages and behaviour. 95–117. along an urban gradient. Biol. Cons. 80, 113–125. 7. Cowling R.M. and Homes P.M. (1992). Flora and 13. Wheeler B.D. (1988). Species richness, species 1. Britton D., Silberbauer L., Robertson H., Lubke R., vegetation. In The Ecology of Fynbos: Nutrients, Fire rarity and conservation evaluation of rich-fen J. Appl. Hoare D., Victor J., Edge D. and Ball J. (1997). The and Diversity, ed. R.M. Cowling, pp. 23–61. Oxford vegetation in lowland England and Wales. Ecol. 25 life-history, ecology and conservation of the University Press, Cape Town. , 331–352. Brenton blue butterfly (Orachrysops niobe) 8. Pierce S.M. (1990). Patterns and processes in south 14. Lewis O.T. Wilson R.J. and Harper M.C. (1998). (Trimen) (Lycaenidea) at Brenton-on-Sea. Unpub- coastal dune fynbos: population, community and land- Endemic butterflies on Grande Comore: habitat lished report for the Endangered Wildlife Trust of scape level studies. Ph.D. thesis, University of Cape preferences and conservation priorities. Biol. Southern Africa, Johannesburg. Town. Cons. 85, 113–121. 2. Avis A.M. and Lubke R.A. (1985). The effect of 9. Manders P.T. (1991). The relationship between forest 15. Shapiro A.M. (1975). The temporal component of wind-borne sand and salt spray on the growth of and mountain fynbos communities in the southwestern butterfly species diversity. In Ecology and Evolution Scirpus nodosus in a mobile dune system. S. Afr. J. Cape Province of South Africa. Ph.D. thesis, Univer- of Communities, eds M.L. Cody and J.M. Diamond, Bot. 51, 100–110. sity of Cape Town. pp. 181–195. Belkamp Press, Harvard University, 3. Hoare D.B. (1994). Assessing successional effects on 10. Van Wilgen B., Bond W.J. and Richardson D.M. Cambridge, Mass.

introduces the field well. The treatment A bridge to first-year chemistry of equilibrium, acid-base equilibria, kinetics, electrochemistry and thermo- chemistry is excellent. Having stated Chemistry – An Introduction for Southern African Students. By Michael the positive, the treatment of physical Clugston, Rosalind Flemming and Daphne Vogt. Pp. 616. Oxford University chemistry has some weaknesses. Press, Cape Town. R350.00. ISBN 0 19 578081 7. Certain topics are covered superficially (such as the description of Lewis struc- tures), while other topics are not cov- This book is unique, as it is the only all layout and presentation are pleasing ered at all (properties of solutions). chemistry textbook specifically de- to the eye. It is written in a style Valence bond theory is relegated to a signed for southern African students at that maintains the reader's interest, short description under organic chemis- university. It is a modified version of while remaining easy to understand try, rather than being integrated into the Advanced Chemistry by Clugston and for the novice and, equally important, physical chemistry section on bonding. Flemming, an A-level school textbook in for students whose first language is In general, the treatment of atomic the United Kingdom. Daphne Vogt has not English. This is done without de- structure, bonding and thermodynamics incorporated material that will be of viating from scientifically acceptable interest to students in our part of the language. is probably at a standard somewhat world. The organic chemistry section is sub- lower than that usually expected of Most introductory chemistry text- stantial and covers more ground than first-year students in this country. books currently prescribed are very most general chemistry textbooks at This book gives the impression of similar to one another and often are not this level. Its high standard of presenta- being a bridge between school and very suitable for local curricula. They tion is one of its strengths and sets it university level chemistry. In this role, it tend to be designed for American uni- apart from competitive texts. It pro- can play an extremely important func- versities and, consequently, hardly vides an introduction to structure and tion, especially for under-prepared cover organic chemistry. This results in reactivity, surveys the functional groups students. Perhaps more examples rele- the necessity to prescribe two first-year and reactivities of the main classes of vant to southern Africa could have been chemistry texts, one general and the molecules, then goes on to deal with included, as suggested by the title, other organic. In many ways, the book biological molecules and finishes with a although this is a minor criticism. Its by Clugston et al. breaks the mould. discussion of spectroscopy and chroma- coverage of organic chemistry will make First, it is divided into the three tradi- tography. The latter topics are seldom it an attractive option as a first-year tional pillars of physical, inorganic, and seen in a text at this level. The overall textbook, as will its price. Nonetheless, organic chemistry. Another unique impression is of an interesting, dynamic lecturers will probably need to provide feature is that it deals with each topic and relevant science, with a reasonable supplementary material for aspects of mainly as a two-page spread. Where a balance between biological and indus- physical chemistry. Whether it will topic requires more than two pages, it is trial aspects of organic chemistry. actually replace existing first-year texts, dealt with as a series of spreads. This The inorganic section describes the or merely supplement them, will depend makes the book student-friendly, deal- periodic behaviour of the elements. The on the curricula of individual teaching ing with concepts in a crisp and to-the- physical properties and reactivities of institutions. point fashion. Matters of interest, or the s- and p-block elements are covered requiring further explanation or expan- in considerable detail. The section con- Timothy J. Egan and David W. Gammon sion are relegated to boxes. In these cludes with an introduction to the transi- Department of Chemistry, respects, the book is refreshing and tion metals. This part is well written and University of Cape Town, novel. As one has come to expect sufficiently comprehensive for the pur- Private Bag, Rondebosch 7701. for introductory books on chemistry, it poses of first-year chemistry. [email protected]; is beautifully illustrated and its over- Overall, the physical chemistry section [email protected]