Aspects of the floral anatomy of the 16 taxonomic sections within Haplopappus (Astereae, Asteraceae) of North America were studied as a means of adding systematic weight to arguments concerning the status of the genus. While some anatomical features, particularly involving vasculature and secretory apparatus, easily characterize some sections, other sections are anatomically quite heterogeneous. Also, correlations between certain pairs of anatomical features (such as presence and abundance of achenial vascular bundles and secretory canals) exist within some sections (for example: Ericameria with many bundles and many canals, Pyrrocoma with few bundles and few canals). Such trends make certain taxa cohesive within their own sections. Cluster analysis was applied to 17 scored anatomical features among 97 taxa. Comparisons are made of phenetic relationships in sections Hazardia and Pyrrocoma from the standpoint of flavonoid chemistry; some agreement between flavonoid chemistry and floral anatomy exists. The rather conventional view of this genus (in North America), as comprised of 16 variously unrelated sections, convenient as it is, is shown to be unnatural and taxonomically strained. Anatomical evidence supports rearranging and/or recategorizing certain sections; Asiris, Ericameria, Hazardia, Isocoma, Oonopsis, Osbertia and Prionopsis are anatomically distinctive, and should be considered as independent genera. The interrelationships of several of these taxa are unclear (especially Hazardia and Blepharodon). Much systematic knowledge, especially anatomical, from the South American taxa in Haplopappus is unavailable. Such further investigation is needed prior to future critical evaluations of the relationships of Haplopappus of the two continents. / Source: Dissertation Abstracts International, Volume: 43-10, Section: B, page: 3116. / Thesis (Ph.D.)--The Florida State University, 1982.

Aspects of the floral anatomy of 35 species (and several subspecies) of goldenasters were studied to help elucidate whether they should be placed in one, two or three genera (i.e. Chrysopsis, Heterotheca, Pityopsis. While some anatomical features, particularly involving vasculature and secretory apparatus, easily characterized some groups, other groups are anatomically quite heterogeneous. Features that proved particularly useful were numbers of vascular bundles, size and frequency of secretory canals, and achene shape and structure. Cluster analysis (UPGMA) was applied to 31 scored anatomical features among 48 taxa. / This study supports the taxonomic concept that three genera of goldenasters exist. However, the genus Heterotheca proves to be rather heterogeneous. One or more of its sections might be worthy of generic recognition. However, adequate materials of section Ammodia and sufficient numbers of species of section Phyllotheca were not available in this study to determine if such recommendations should be made. / With the data at hand, the recognition of three genera of goldenasters, Chrysopsis, Heterotheca, Pityopsis, appears to be the best classification to maintain. / Source: Dissertation Abstracts International, Volume: 47-06, Section: B, page: 2281. / Thesis (Ph.D.)--The Florida State University, 1986.

Source: Dissertation Abstracts International, Volume: 30-02, Section: B, page: 0519. / Thesis (Ph.D.)--The Florida State University, 1968.

An anatomical survey of 202 species in 24 genera of subtribe Pleurothallidinae (Orchidaceae) was conducted to circumscribe genera on a more natural foundation and to elucidate very obscure generic relationships. Results of this study indicate which vegetative characters are of diagnostic value and at what taxonomic level. Most systematically important characters are associated with the leaf, and include features of trichomes, cuticle, epidermis, hypodermis, spiral thickenings, and number of vein series. The secondary stem is of limited usefulness at higher nomenclatural levels. Number of velamen cell layers and protoxylem poles in the root may be reliable taxonomic indicators with certain limitations and precautions. The established subtribal phylogenetic trends of reduction of pollinia and specialization of the perianth may be correlated with particular anatomical trends, which are reductionary also or involve specializations directly related to the water relations of the epiphytic habit. Secondarily, cluster and factor analyses of 34 genera or species complexes were performed with a data matrix derived from scorings of 45 continuous or discrete variables in order to identify phenetically similar groups and to indicate phenetically isolated taxa. Regardless of the statistical clustering methods applied, Dracula, Dresslerella, the Pleurothallis alexandrae complex, and the Pleurothallis peduncularis complex are measurably distinct from each other and all other Pleurothallidinae. The last two of these taxa undoubtedly warrant generic rank. / Source: Dissertation Abstracts International, Volume: 42-10, Section: B, page: 3932. / Thesis (Ph.D.)--The Florida State University, 1981.

The phylogenetic relationships of the Cypripedioideae are adumbrated by the Wagner Groundplan-divergence method. The mutual resemblance between paleotropical Paphiopedilum and neotropical Phragmipedium is doubtfully superficial since both share several vegetative features, deciduous perianths and similar floral bud development. For these genera a simplified classification is proposed, and one new taxonomic combination is provided. / Selenipedium grades into Cypripedium via C. irapeanum and C. californicum. The correlation of reduced vegetative features with increasing latitude suggests that temperate climates have altered the northern taxa most. By eliminating these features from cladistic analysis, Cypripedium arietinum (for which the genus Criosanthes is recommended) is parismoniously distinct from the Selenipedium-Cypripedium clade. / Similar flowers of Phragmipedium schlimii and Paphiopedilum subgenus Brachypetalum relate to neoteny, since the floral parts resemble those of young flower buds of related species. Their superficial floral similarity is interpreted as a convergence. / Chromosome numbers are reported for five species of Phragmipedium and nine species of Paphiopedilum. Since the basal chromosome number is interpreted as 2n = 20 for Cypripedium, Criosanthes, and Phragmipedium, this is probably the basal number for the subfamily. Although centric fission accounts for the upward aneuploid series in Paphiopedilum (2n = 26-44), higher metacentric arm ratios in the aneuploids than in the non-aneuploids suggest that centric fusion has occurred as well. It is argued that both fission and fusion have karyologically repatterned Paphiopedilum section Barbata with concurrent adaptation to forest floors. / Under a vicariance model, the cladograms reveal geographic patterns in Paphiopedilum, Phragmipedium, and the Selenipedium-Cypripedium clade with the primitive taxa southernmost. To explain the seemingly incongruous patterns with a necessary Laurasian origin, it is suggested that the southernmost populations have followed habitats similar to the ancestral ones in response to post-Miocene cooling. This mechanism may offer a partial explanation for accumulation of primitive angiosperms on the Asiatic islands which have largely arisen since the Miocene. / Contrary to popular belief, some slipper orchids are very advanced, and there is little evidence that the Cypripedioideae is a relic group at an evolutionary dead-end. / Source: Dissertation Abstracts International, Volume: 42-08, Section: B, page: 3096. / Thesis (Ph.D.)--The Florida State University, 1981.

Source: Dissertation Abstracts International, Volume: 36-06, Section: B, page: 2596. / Thesis (Ph.D.)--The Florida State University, 1975.

Source: Dissertation Abstracts International, Volume: 38-05, Section: B, page: 2011. / Thesis (Ph.D.)--The Florida State University, 1977.

Source: Dissertation Abstracts International, Volume: 20-08, page: 3038. / Thesis (Ph.D.)--The Florida State University, 1959.

Source: Dissertation Abstracts International, Volume: 27-04, Section: B, page: 1048. / Thesis (Ph.D.)--The Florida State University, 1966.

Source: Dissertation Abstracts International, Volume: 27-04, Section: B, page: 1049. / Thesis (Ph.D.)--The Florida State University, 1966.