Zs. P. Komáromy szerk.: Studia Botanica Hungarica 12. 1977 (Budapest, 1977)
Radics, Ferenc: The identification of Rorippa species and hybrids (Cruciferae) based on external morphological features of their seeds
previously, for 2-3 days, in a mixture of one part of glycerine and two parts of water. During this procedure the formation of sline, or its absence was controlled; it served also to protect the seeds from drying out over a long period of time. The seed-analysis from the point of view of external morphological characteristics was carried out according to the traditional method. However, owing to the small size of the seeds, I was compelled to use a microscope with the magnifying scale 2. 5 x 6. 3, 6. 3 x 6. 3 and a projective 6. 3 MF, a PRONTOR PRESS camera and ORWO NP 15 roll films. I examined the size and shape of seeds of the basic species, the morphological features of the .hilum region, pattern of the surface of seed coat (testa), that of its sclerotic layer, all characteristics originated from the structure of the seed coat perceptible from outside, too, occasionally a special colour or some other hereditary morphological features. My conviction that this method was employable, was strengthened by the detailed comprehensive examinations of VAUGHAN and WHITEHOUSE (1971) as to the structure of the seed coat and further morphological features referring to the Rorippa species (Cruciferae). The results of similar examinations of CERNÖHOR SKY (1947) gave me further assistance. RESULTS VAUGHAN and WHITEHOUSE (1971) described the seeds of three Rorippa species (R. islandica, R. py^enaica and R. silvestris) from their external morphological features. CERNOHORSKY described four Rorippa species (R. amphibia, R. austriaca, R. islandica and R. silvestris) on the basis of the morphological characters of seeds. Consequently, it became necessary to have a description of external morphology of the seeds of six Rorippa species, especially in order to clear up the hybrid forms, and in addition to those named above, it was wanted to describe the external morphological characteristics of the seeds of Rorippa proliféra HEUFFEL (1854). A detailed description of the latter Rorippa species is to be found in a publication of HEUFFEL (1858) among the species of the Carpathian Basin. Before enumerating the morphological features of the seeds of basic species, to observe the seeds of hybrids too I compile a table in order to give a survey of the feature categories and to clear up the termini employed (Table 1).
