Resumen de Anotaciones a la anatomía comparada de las Umbelíferas

Rafael Lucas Rodríguez S

• español

  Se suman aquí datos relativos a cuatro especies herbáceas de umbelíferas a un estudio más extenso en que se describe y compara el xilema secundario de un número de especies de umbelíferas y araliáceas. Incorporando estas es­pecies a las previamente estudiadas, resulta Daucus Carota muy avanzada en sus características anatómicas, así como 10 es por su morfología y posición sis­temática; Arracada xanthorrhiza viene a ser una especie moderadamente avan­ zada, aún en comparación con otras especies del mismo género, y Famiculum vul­gare comparable a otras umbelíferas perennes de porte herbáceo robusto. Sanicula crassicaulis, en otra subfamilia, resulta muy avanzada dentro de la familia co­mo su congénere S. desertícola. Se comenta la posibilidad de que puntuaciones escalariformes alteradas formando vórtices o curvas sean una característica avan­zada, que se observa en varias especies de esta familia.

• English

  Descriptions and measurements of the secondary xylem components of four herbaceous Umbelliferae are presented (Table 1), as an addition to a comparative study concurrently in print, comprising 36 Umbelliferae and 38 Araliaceae (27). If the species here considered are integrated into the foregoing series, Daucus Carota is shown to have highly advanced characteristics, in har­mony with its systematic position and morphologic characteristics. Arracada xan­thorhiza, a South American perennial herb whose rootstock . puts out fleshy lateral growths which constitute the edible "arracacha", appears to be moderately advanced, slightly ahead of its more shrubby congeners. Faeniculum vulgare, a perennial herbaceous species, is comparable to other Apioid species of like habit such as Conium maculatum, and occupies an intermediate position in the family. Sanicula crassicaulis, a western North American herbaceous species, appears also to be well advanced, stressing the independent progress which has taken place within each sub-family. A frequent modification of scalariform lateral-wall pitting, resulting in the formation of whorled patterns is described in vessel elements of Arracacia xanthorhiza and Daucus Carota. Similar patterns have been observed in Arra­cada Wigginsii, Bupleurum longiradiatum, Sanicula deserticola and Pteryxia pe­traea. Formation of such patterns might be interpreted as a result of the reduction of vessel-element length leading to cell-wall formation as in isodiametric cells; or else, it may be an advanced modification of scalariform pitting, perhaps related to whorled patterns of "tertiary" thickening of lateral walls, reported in Heteromorpha arborescens, Heteromorpha trifoliata, Bupleurum fruticosum and also in Astrotrichia pterocarpa (araliacae). If this is the case, the whorled pat­terns of pitting might stand, with relation to typical scalariform pitting, as the whorled patterns of "tertiary" thickening to the simpler helicoid patterns com­mon in Bupleurum fruticosum and in Heteromorpha, in Araliacae such as Nothopanax arboreus and Nothopanax Colensoi, as well as in Garrya Veatchii and G. Wrightii.