A CRITICAL REVISION OF CERTAIN TAXONOMIC GROUPS OF THE MALVALES
1935; Wiley; Volume: 34; Issue: 1 Linguagem: Inglês
10.1111/j.1469-8137.1935.tb06824.x
ISSN1469-8137
Autores Tópico(s)Mediterranean and Iberian flora and fauna
Resumoare poisonous.The majority have tenacious fibrous inner bark or bast, and mucilage canals, especially m fhe unlignified organs; mucilage is lacking from fhe section Elaeocarpaceae of some wnfers, but if is often replaced by a bitfer principle.If IS remarkable fhaf m so well-known and widespread an order, no general agreement as regards subclassificafion has been reached.This is doubtless attributable to the peculiarity and homogeneity of the Malvales.Superficially, they all appear ver>' similar, and only a careful examination can reveal the underlying differences which break them up into distinct and definite families.From fhe point of view of practical forestry, it is of importance to know just how far these families extend.The object of fhe present study is to define the families of fhe Malvales by characters which are readily ascertainable, and to revise the more detailed classification of certain families.The recent publication of two papers(4,5) on the microscopical wood sfructure of the order, has afforded valuable data not hitherto available.FORMER CLASSIFICATION Linnaeus (12) in Philosophia Botanica, 1763, was the first fo apply the name " Columniferae" to one of his natural groups or "fragmenta."This included the genus Gossypium and most of the modern Malvaceae; Theobroma was placed with fhe Tiliaceae in fhe group Culminiae; but both these groups included genera now excluded from fhe Malvales.The Genera Plantarimi of Benfham and Hooker(2) gives fhe first sound and practical classification of fhe group.In this, fhe small family Chlaenaceae is placed in cohort V, Gutfiferales, which have stamens indefinite and calyx imbricate; and cohort VI, Malvales, is defined, within the series Thalamifiorae of the Polypef alae, as having the stamens indefinite and the calyx valvate.The placentation is defined as axile.The cohort Malvales is divided info three families, the Malvaceae, which include the Bombaceae, are distinguished by their unilocular anthers, and the Tiliaceae by their free stamens.No precise distinction is drawn between the Tiliaceae and the Sterculiaceae, which are described as having stamens monadelphous, or opposite the petals in clusters or singly; this description would apply very well to many of the Tiliaceae (e.g.Tilia).Nevertheless, this classification of the families would be satisfactory but for fhe facf that the families are too large and hefero-
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