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Six clearly separable evolutionary levels in the floral evolution of the Ranunculaceae were found to coincide with the six corresponding stages of sensory development of their pollinators as follows: amorphic -> haplomorphic -> actinomorphic -> pleomorphic -> stereomorphic-zygomorphic. This is a basic trend of floral evolution, fully recapitulated in a single family. Except for the first (amorphic), all upper levels are represented in the present-day floras as clearly separable type-classes. They are therefore accessible to direct observations and experimental study. Extensive statistical data on flower visitors of the Ranunculaceae confirm the proposed theory of the mutual interrelationship between the evolutionary levels of flower types and sensory stages of pollinating insects. The new picture, obtained by this study, gives us a better understanding of the evolutionary relationship between insects and plants and explains the extreme diversity in the floral structure of the Ranunculaceae.
In the present revision of Sabia the number of species has been reduced from 55 to 19, including two that are described as new. Below the specific level, a new subspecies and a new variety are described, whereas some new infra specific combinations have been made. Most of the reduced species have been included in the synonymy of S. campanulata, which consequently represents the most complex and most variable species of the genus. Next to a general key, some regional keys are given as on the one hand some widespread species are locally far less variable than taken over their whole area, on the other hand well-delimited species from different regions may be very uniform in some points.
The seed collection of the species of the Gesneriaceae on which this study is based was obtained, for the most part, during a number of visits to the herbaria of the Smithsonian Institution, Washington, D.C., and the Royal Botanical Garden of Kew, London, and Edinburgh, Scotland. The seed collection comprises well over 800 samples of about 700 species of the Gesneriaceae, representing 113 genera of the 127 in the family, and provides a good taxonomic representation of the Gesneriaceae. Following an examination of all the samples in the seed collection, over 300 species of the 113 genera were selected to represent the wide range of seed morphology characters observed among the examined species of the Gesneriaceae. A system with which to analyze and diagnose seed surface morphology, designed by the author, is based on a format of six major categories and 60 tertiary terms of seed morphology characters and a companion diagnostic table. The categories are arranged in a sequence of increasingly smaller seed characters, ranging from seed shape to the ultrastructural characters of the individual cells. To ensure that the system would also apply to seed plants in general, the seeds, achenes and nutlets of a wide variety of species from families other than the Gesneriaceae were examined. Twenty species from 13 families other than the Gesneriaceae were then selected and are included in this study and, together with the Gesneriaceae, represent eight of the ten subclasses of the flowering plants (Cronquist 1968). The seeds, achenes and nutlets of all the species included in this study are illustrated with SEM photomicrographs on the 54 plates of the Seed Atlas, and the seed morphology data of each species are recorded on the diagnostic tables that face each of the Atlas Plates. To facilitate the comparison of the taxa of the Gesneriaceae, and to assist in the identification of the seeds of the examined species of the Gesneriaceae, the seed morphology data are also recorded on a summary table at the genus, tribe, subfamily and family levels. The seed morphology of the Gesneriaceae is compared and contrasted with the current classifications of the family at the species, genus, tribe, subfamily and family levels. The seed analysis system designed for this study has proven to be a rapid, efficient, uniform, objective method to deal with the analytical, diagnostic, and taxonomic aspects of an investigation of seed morphology. In addition, the system readily lends itself to the substitution or addition of terms and categories if needed, or to programming for a computerized analysis of seed morphology. It is hoped that the system will prove useful to other investigators, as well as prove helpful to standardize future investigations of seed
morphology.
In this paper all the Japanese species of the family Lejeuneaceae were critically reviewed. As the result four subfamilies, twenty-one genera, and seventy-eight species were recognized under the family. Discussions were made on the relationship of the genera within the family and with other families (Tables 1-4). The new subfamily Jubuloideae was established (the type is Jubula), and the genera, Hattoria and Nipponolejeunea, were included in it. More than thirty species were reduced to synonymy under others, and eighteen new combinations were made. The seven types of distribution were recognized, according to the distribution patterns of species in Japan (Map 1, Table 5).
In the field of mycology at the present time, many of the fungi which are most frustrating to attempt to classify are the Ascomycetes of pyrenomycetous nature. While it is possible to identify many species from descriptions in the literature, the position of these species in respect to one another is difficult to assign. A major step toward a modern classification was provided by Luttrell (1951b, 1955), where he expanded Miller's (1928) and Nannfeldt's (1932) recognition of differences between the subclasses Loculoascomycetes and Euascomycetes and utilized the basic characteristics of the ascus and of centrum development to delimit major groups. Currently, studies of generic types by a number of investigators are providing a firm base for the assignment of taxa to the correct genus. Several systems of classification are available, but none of these is entirely satisfactory. The following synopsis is offered as an alternative arrangement of one order in the Loculoascomycetes. For the present, the system applies to fungi known from temperate North America. The classification probably will have to be expanded and emended as tropical and temperate fungi from other continents are studied. My intention is to continue with similar studies of taxa in the other orders of both Loculoascomycetes and Euascomycetes.