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

Rorippa barbaraeoides (TAUSCH) CELAK is, as a subspecies of Rorippa anceps (WAHL) a hybrid of R. amphibia and R, silvestris, (I.e. 191) However, one year later he modified his statement saying that the R. barbaraeoides was a hybrid of R. austriaca x silvestris, and R. anceps (WAHL») was not a hybrid of R. amphidia x silvestris, but R. amphibia x palustris. For the hybrid R. amphibia x silvestris we may give the name R. repens BORB. (BORBAS 1879 1. c. 11). V TOMSOVIC determined the taxon R. x barbaraeoides as a hybrid of R_. amphibia and R. silvestris

. What is more, after a revision of the specimens preserved in the Botanical Department of the Hungarian Natural History Museum he accordingly corrected the schedules of all such hybrid specimens. CELAKOVSKY (1875) believed that the taxon R. barbaraeoides TAUSCH was nothing else but a hybrid R. amphibia x silvestris (I.e. 458) and he thought it better to cast off the name R. anceps (sub Nasturtio) WAHL, with a view to its manifold use. With the he}p of his complementary ecological and cenological examinations, TOMSOVIC managed to concretize several conclusions of BORBAS, mentioned in the introduction of this paper, he had drawn merely on floristic basis. TOMSOVIC stated that in view of the fact that some Rorippa species have not been separated from each other, neither by a "sterility barrière" nor by geographical isolation, they may have only been separated ecologically. This ecological isolation, however, has been disturbed by frequent anthropogen modifications of their living place. Just for this reason, a large number of hybridizations took place; the fertile hybrids, owing to .their greater capacity of accomodation, were able to subsist (1. c. 37). MATERIAL AND METHODS For the present examinations I used the exsiccata from the Herbarium of the hundred years old Botanical Department of the Hungarian Natural History Museum. These dried plants were collected in the Carpathian Basin. Among these specimens and their fertile or sterile seeds, I examined first of all the Rorippa species collected and determined by BORBAS, SIMONKAI, JAVORKA and SOO. For comparative purpose, I examined also others collected or described by various other writers. Samples were taken mostly from herbarial specimens which the authors described very well (single specimens, in masses, or in association with other Rorippa species). The method of taking samples was the following: from the sheet of the Rorippa specimen chosen for examination, I analyzed all seeds of three pods, taken from different flower stalks from the point of view of their external morphological features. Seeds have been soaked,