摘要:

SummaryNumerical taxonomy is rarely used to compare plant families with one another. This is probably because it is very difficult to organize characters in such a way as to totally express the variability at this rank. To avoid this problem, we evaluated the frequency of the character in the family, by calculating the percentage of genera possessing the character in question. The study was done on the subclassHamamelididae, sensu Takhtajan (1969), which comprises 22 families. For most of the families, 130 morphological and anatomical characters were used to obtain values.The data were treated by principal coordinate analysis and by hierarchic agglomeration cluster analyses. These two types of analysis were built upon Gower (1971) similarity coefficient. The analyses of the ordination and the phenogram has permitted us to divide the subclassHamamelididaeinto three well‐delimited phenetic groups. The first group comprises the so‐called primitive families:Eupteleaceae, Tetracentraceae, Trochodendraceae, Myrothamnaceae, Cercidiphyllaceae, Platanaceae, Hamamelidaceae, and is often seen as the basis for linkage with other subclasses. The families of group three,Myricaceae, Moraceae, Ulmaceae, Betulaceae, Fagaceae, Juglandaceae, Rhoipteleaceeae, UrticaceaeandCannabaceae, distinguish themselves by evolved characters and can be considered as the nucleus of theAmentiferae. The second group which comprisesCasuarinaceae, Eucommiaceae, Balanopaceae, Didymelaceae, LeitneriaceaeandBarbeyaceae, does not seem to possess any unique characters. These families possess characters that are found either in group one or group three or in both. This explains why the second group is made up of families which are phenetically intermediate between groups one and three.This study shows also that theBalanopaceaepresents more affinities with theTrochodendrales‐Hamamelidalescomplex than theFagales. Also, it seems that theLeitneriaceaealthough close to theAmentiferae, more or less insert themselves between that group and theHamamelidales. The results obtained concord well with several modern classification systems and particularly with the one proposed by Takhtajan (1969) except for the positions in which he places theLeitneriaceaeand theBalanopaceae.

ISSN:0040-0262    

DOI:10.2307/1219679

出版商:Wiley    

年代:2019

数据来源: WILEY

摘要:

SummaryPrincipal component analysis (PCA), Wells' hybrid distance diagram, principal coordinate analysis (PCO) using weighted Gower metrics, and canonical variate analysis (CVA) were compared using data from artificial crosses of sunfish (Lepomis) and putative hybridization inJuniperus. The results were similar between the two data sets in that using the weighted characters (F ratios from ANOVA of the parents) produced well resolved parental groups and generally ordinated the hybrids between the parents. The F weighted PCO and Wells' distance diagrams were found to be better suited for the analysis of hybridization than PCA or CVA. Several limitations of PCA and CVA are discussed.

ISSN:0040-0262    

DOI:10.2307/1219680

出版商:Wiley    

年代:2019

数据来源: WILEY

摘要:

SummaryA Monte Carlo procedure is described for identifying linkage between objects each of which is represented as the multivariate centroid of a group of replicates. An example of an application of this procedure to a study of geographic variation demonstrates the usefulness of the procedure for the recognition of innate group structure.

ISSN:0040-0262    

DOI:10.2307/1219681

出版商:Wiley    

年代:2019

数据来源: WILEY

摘要:

SummarySolanum appendiculatumH. et B. ex Dun.,S. connatumCorr., andS. inscendensRydb. constitute the single dioecious species,S. appendiculatum. These taxa are fully intercompatible and morphologically very similar. They were distinguished by differences in style length and in the degree of filament fusion; however, the first character is associated with the gender of the plants, and the latter shows variability and inheritance patterns not associated with species boundaries.

ISSN:0040-0262    

DOI:10.2307/1219682

出版商:Wiley    

年代:2019

数据来源: WILEY

ISSN:0040-0262    

DOI:10.2307/1219683

出版商:Wiley    

年代:2019

数据来源: WILEY

摘要:

SummaryMathematical analysis of the flavonoid pattern of twenty populations ofLathyrus pratensisshows that there is no difference between diploid and tetraploid samples in flavonoid metabolism. But we noted obvious differences between the populations growing in a wet habitat and those growing in a dry one, the flavonoid biosynthesis evolution of these being more advanced. Moreover, in both diploids and tetraploids, the hypothesis of ancestors from different geographical origins is reinforced by slight variations in the flavonoid metabolism expression on the samples studied.

ISSN:0040-0262    

DOI:10.2307/1219684

出版商:Wiley    

年代:2019

数据来源: WILEY

摘要:

SummaryAbout 2000 watercolor paintings, made by the artists of the 18th‐century Spanish expedition to New Spain, and lost since 1820, were found in Barcelona and acquired by the Hunt Institute for Botanical Documentation, Pittsburgh. They will constitute an important resource for those hoping to fix the identities of the species of plants described by A. P. de Candolle on the basis of these paintings and the duplicate set at the Conservatoire Botanique, Genève.

ISSN:0040-0262    

DOI:10.2307/1219685

出版商:Wiley    

年代:2019

数据来源: WILEY

摘要:

SummaryJosé Celestino Mutis was one of the most important of the early botanists in Colombia. One of his few publications was “El Arcano de la Quina” which appeared in thePapel Periódico de Santafé de Bogotá, a small‐format weekly newspaper, between the 10th of May, 1793, and the 7th of February, 1794. In a table which appeared on page 465 of issue 111, 11 October 1793, he validly published four species ofCinchona, C. lancifolia, C. oblongifolia, C. cordifoliaandC. ovalifolia.

ISSN:0040-0262    

DOI:10.2307/1219686

出版商:Wiley    

年代:2019

数据来源: WILEY

摘要:

SummaryThe use of mixed collections has become widespread in moss taxonomy as a short‐cut for more rigorous examination of the genetic basis of morphological characters. The reasoning behind this approach is that closely related but morphologically different plants growing intermixed must be experiencing the same environment. Therefore, the morphs must be genetically distinct and can be treated as separate taxa. The method is simple to apply and has been extended from field observations of mixed populations to mixed specimens in herbarium packets. There are serious problems with the logic and methodology of this approach. It overlooks the possibility of microenvironmental variation and requires unreasonably restrictive assumptions about genetic variability in bryophyte populations. The mixed collection method should be abandoned entirely, and more rigorous experimental tests, such as uniform garden cultivation and reciprocal field transplants, employed.

ISSN:0040-0262    

DOI:10.2307/1219687

出版商:Wiley    

年代:2019

数据来源: WILEY

摘要:

SummaryA bibliographic summary ofActa Phytotaxonomica Sinicais presented. Publication dates, numbers per volume and other pertinent information were determined in part from an examination of holdings in the Institute of Botany, Academia Sinica, Beijing.

ISSN:0040-0262    

DOI:10.2307/1219688

出版商:Wiley    

年代:2019

数据来源: WILEY