South Africa

Two new Androcymbia (Colchicaceae) from Western South Africa
J. PEDROLA-MONFORT, N. MEMBRIVES FERNÀNDEZ, & J. M. MONTSERRAT MARTÍ Fontgueria 54(2): 7-9. (1999). Abstract. Two new taxa are described from the Cape region (Western South Africa): Androcymbium walteri and A. albanense Schönland subsp. clanwilliamense (Colchicacece). Resumen. Se describen dos nuevos táxones de la región Capense (Sudáfrica occidental): Androcymbium walteri y A. albanense Schönland subsp. clanwilliamense (Colchicacece). Résumé. Deux nouvelles taxa de I’Afrique sudoccidental sont décrites: Androcymbium walteri et A. albanense Schönland subsp. clanwilliamense (Colchicacecp). A NEW SPECIES FROM THE WESTERN OF SOUTH AFRICA: Androcymbium huntleyi (Colchicacece) Abstract. A new species is described from the Cape region (Westem South Africa): Androcymbium.

huntleyi Pedrola & al. (ColchicaceaeJ. Resumen. Se describe una especie nueva de la región Capense (Sudáfrica occidental): Androcymbium huntleyi Pedrola & al. (ColchicaceaeJ. Résumé. Une nouvelle espèce de I’Afrique sudoccidental est décrite: Androcymbium huntleyi Pedrola & al. (Colchicaceae) Control of PAR-saturated C02 exchange rate in some C3 and CAM plants S.L. NIELSEN, S. ENRÍQUEZ and C.M. DUARTE BIOLOGIA PLANTARUM 40 (I): 91-101, 1997/98 Abstract We measured PAR-saturated CO2 exchange rate (CER), and leaf N, P and chlorophyll (Chl) concentrations in 21 plant species, selected to encompass as broad a range in specific leaf area (SLA) as possible, and encompassing non-succulent C3 as well as succulent CAM plants. We worked with plants growing under uniform conditions in the facilities of a biological research station to ensure that any correlations found were due to inherent, genetically controlled, relationships between the measured parameters and not due to variations in resource availability in different habitats. We found CER to be strongly correlated to SLA, leaf N concentration and Chl.

cóncentration. CER increased much faster with increasing leaf N concentration (CER ≈ N3.1) than with increasing SLA (CER ≈ SLA1.2). CER also increased much faster with leaf N concentration than with increasing Chl concentration (CER ≈ Chl1.3), indicating the photosynthetic N-use efficiency (NUE) to be higher for plants with high N concentration than for plants with low N concentration (NUE ≈ N2.1). Analysis of covariance showed that these relationships exist even when comparing plants of widely different growth forms – succulent or non-succulent, and of different photosynthetic pathways, as the C3 and CAM plants compared here. Testing against scaling coefficients calculated using dimensional analysis, showed that the scaling of N, Chl and CER against SLA was not merely a result of diluting N and Chl with carbon in thicker leaves but that SLA, probably through influencing light aborption and/or CO2 difusion pathway, plaed an independent role in controlling CER.

THE ANDROCYMBIUM SPECIES OF THE CANARY ISLANDS Pedrola-Monfort, J. & J. Caujapé-Castells Curti’s Botanical Magazine 15(1): 67-77 Summary. The history, taxonomy, biology and cultivation ofthe Canary Islands endemics Androcymbium hierrense A. Santos and Androcymbium psammophilum Svent. (Colchicaceae) are discussed, together with hypotheses about their mainland origin; full botanical descriptions and
illustrations are provided.