Nine populations of Tilia dasystyla Steven (Tiliaceae) in the Crimean mountains (Krymskiye Gory), including the type locality at Kastel Dag, were studied in the field and sampled by collection of herbarium specimens. This material was compared with specimens referred to Tilia hegonifolia Steven collected in Crimea, the Caucasus and Iran. Measurements or scores of 21 morphological characters made on the dried material were analysed by principal components analysis and logistic regression. These analyses demonstrated that the majority of trees could be correctly allocated to either Crimea or the Caucasus and Iran on the basis of the shape of their leaves and the area of their bracts. In addition there are differences of leaf and bract texture and bract colour which can be observed in fresh material. Chromosome counts showed that Crimean trees and one Caucasian tree are tetraploid (2n = 164). It is proposed that the Crimean, Caucasian and Iranian trees be treated as a single species with at least two subspecies: Tilia dasystyla Steven subsp. dasystyla from Crimea and T. dasystyla Steven subsp. caucasica (V. Engl.) Pigott from the Caucasus and Iran.

Dussia atropurpurea is a new species found in Costa Rica and Panamá. It differs from all other Dussia species in this region in its dark purple sarcotesta. The only other species of Dussia with a sarcotesta of this colour is the Amazonian D. tessmannii which is clearly distinct morphologically. Sarcotesta colour is an important character for species delimitation in Dussia, but is infrequently recorded.

The newly described white-flowered annual Sedum ince closely resembles S. eriocarpum and the annual forms of S. hispemicum (S. longibracteatum), but differs from the former by its alternate instead of verticillate leaves, and from the latter by the 5-merous instead of 6 9-merous flowers and the ripe follicles which are divergent instead of patent and lack the distinct lips along the ventral suture. Molecular phylogenelic analyses indicate that S. ince is but distantly related to S. eriocarpum as well as to S. hispemicum. It belongs to a cytological distinct lineage of Sedum subgenus Gormunia sporting a basic chromosome number of x = 7. Within this lineage, however, S. ince holds a unique position and consequently it is classified in the monotypic S. series Elegans.

A new species of Passiflora is described from the Andes of Colombia. Passiflora formosa T. Ulmer is characterized by its densely tomentose ovary, the 5–7 petiolar glands and the large leaves which are up to 19cm long. It most closely resembles P. lanata and P. cuatrecasasii. The differences between these species are discussed.

Studies on recent collections of mature fruiting material of Prangos bornmuelleri Hub.-Mor. & Reese have resolved the taxonomic placement of this enigmatic species. The new monotypic genus Ekimia H. Duman & M.F. Watson is proposed to include this taxon: E. bornmuelleri (Hub.-Mor. & Reese) H. Duman & M.F. Watson comb. nov. Two new Prangos taxa, P. platychloenae Boiss. ex Tchih. subsp. engizekensis H. Duman & M.F. Watson subsp. nov., and P. heyniae H. Duman & M.F. Watson sp. nov., are also described.

Rhytidocaulon P.R.O. Bally is reviewed. The relationships with other genera are discussed in the light of the character assessment carried out and it is suggested that it is closest to Caralluma R. Br. subg. Caralluma and Echidnopsis Hook. f. Descriptions of the genus and the eight known species are provided.

The results of karyological analyses and SEM micromorphological observations on vegetative and reproductive structures of the critical genera Gastrocotyle, Hormuzakia and Phyllocara (Boraginaceae: Boragineae) are presented and discussed in relation to their taxonomic position within the tribe. Each of these monotypic genera is characterized by distinctive features in stigma morphology, papillar pattern, structure of faucal scales, development of the hairy annulus at the base of the corolla tube and ornamentation of the mericarp coat surface. G. hispida and H. aggregata showed 2n = 16 and complements of medium-sized and very large chromosomes, respectively. P. aucheri was characterized by a tetraploid set of 32 chromosomes including a group similar to those of Anchusa and a group closer to those of Nonea in terms of size and centromcric position. This species could have an allopolyploid origin, resulting from the hybridization of members of these two genera. Along with distinctive traits in inflorescence structure, fruit shape and pollen morphology, karyological and micromorphological characters determine sharp phenetic discontinuities from Anchusa, from which these plants should be kept generically separated. At the same time, the presence of relevant autapomorphies in each of the three genera prevents them from being merged in a single genus.

Twelve populations of six Lycium species were analysed for karyotypie characters and seed storage proteins using multivariate statistical methods. All reported chromosome numbers (mostly new) are 2n = 24 (x = 12). Karyotypes were symmetrical and placed in 1A and 2A classes of Stebbins karyotype classification. Cluster analysis of karyological and protein data revealed variations among the populations of L. depressum and L. ruthenicum, and supports close relationships of L. kopetdaghi and L. depressum with L. makranicum, and L. shawii with L. edgeworthii.

Two new species of Aeschynanthus from Borneo, A. argentii Mendum and A. pseudohybridus Mendum, and one from Palawan (Philippines), A. batakiorum Mendum & Madulid, are described and illustrated.

Three new species of Bhutanese orchids, Aphyllorchis sanguinea, Cheirostylis sherriffii and Hetaeria pelota, and one new Sikkimese species, Lecanorchis sikkimensis, are newly described. Their generic placement and affinities are discussed. A new combination in Cheirostylis is made for the Taiwanese Zeuxine tabiyahanensis Hayata. Records of five orchid species new to Bhutan are also presented.

Three new species and one new subspecies of Stipa are described from the E Himalaya: S. jacquemontii subsp. chuzomica and S. bhutanica which appear to be endemic to Bhutan: S. milleri from Nepal, India (Sikkim) and Bhutan and S. rohmooiana from India (Sikkim).

An analysis was made of the floristic composition of 45 savanna sites located throughout the southern neoarctic and neotropics. A total of 533 woody species were recorded from published and reliable unpublished floristic lists; of these, 234 species (44%) were from 10 Brazilian cerrado sites, with 187 (80%) of them restricted to the cerrado biome. The cerrados were clearly shown to be the most diverse New World savanna system with a high degree of endemism. The data were analysed using two multivariate techniques: TWINSPAN and DCA. Four phytogeographic zones were identified: Central Brazil and Bolivia extending to Southern Amazonia; north of Amazonia extending across the isthmus of Central America and including the Caribbean; Belize, Guatemala and Southern Mexico; and north of the Mexican Plateau. The analyses revealed gradients of floristic variation associated with latitude and longitude, and showed the great heterogeneity of savanna vegetation.