Survey and Morphology of Selected Groups of Early Land Plants

对形态和解剖保存完好的早泥盆世植物分类群进行了详细的研究，以参考三分生植物或有问题的亲缘关系。在确定它们与主要蕨类群的可能关系、完善分类界限和结构或谱系分歧的假设模式方面有用的特征应该产生。具体项目包括研究加拿大和德国的裸藻和Pertica相关植物，以便更好地描述三分生植物的特征，并建立与其他植物组的系统发育关系假说。将检查Taeniocrad类型的轴，以确定所代表的分类群的数量并评估它们的关系。关于遗骸的形态和亲和力的更多信息将被获得，这些遗骸类似于假定的配子植物钙藻。为了更好地评估属和种之间的关系，继续研究几种动叶植物类型。各种技术，包括脱胶、酸浸渍、薄片、扫描电子显微镜观察、全厂重建、结构同源性假说和系统发育分析方法，将被适当地使用。这项研究将扩大和完善在系统发育和进化分析中有用的特征序列，产生一些谱系关系的新假说，并为加拿大东南部早泥盆世植物群的组成和多样性提供新的信息。

Detailed investigation of morphologically and anatomically preserved Early Devonian plant taxa referable to trimerophytes or of problematical affinities is proposed. Characters useful in determining their possible relationships to major pteridophyte groups, refining taxonomic circumscriptions, and postulation patterns of divergence of structures or lineages should result. Specific projects include study of Psilophyton and Pertica- related plants from Canada and Germany in order to better characterize the trimerophytes and to develop hypotheses of phylogenetic relationships with other plant groups. Taeniocrad- type axes will be examined to determine number of taxa represented and to evaluate their relationships. Additional information about morphology and affinities of remains similar to the putative gameotophyte Caliculiphyton will be obtained. Several zosterophyll types continue to be studied for the purpose of better evaluating generic and species relationships. A variety of techniques, including degagement, maceration in acids, thin-sectioning, SEM observation, whole plant reconstruction, hypotheses of homology of structures, and phylogenetic analytical methods will be employed as appropriate. This research will expand and improve the array of characters useful in phylogenetic and evolutionary analyses, generate new hypotheses of relationships of some lineages, and contribute new information about the composition and diversity of early Devonian floras of southeastern Canada.