The vegetation of alpine meadows on the Dinarid Mts. in mainly composed by Arctic-Alpine (24.1%) and Oromediterranean-Illyric (37.5%) species. From Northwest to Southeast the former tend to decrease, the latter to increase, which indicates that this kind of vegetation belongs to the oromediterranean region.
In the Friuli-Venezia Giulia Region (NE-Italy) three populations of Seseli elatum agg. occur, which have different altitude ranges and different ecology. It is generally difficult to distinguish these three taxa by classical taxonomical characters. This paper presents a first contribution to the solution of the problem. We have examined the classical morphological characters, plus microcharacters of the fruit surface (SEM), and the secretory structures (canals, ampullae, vittae). We propose some new discriminant characters. The morpho-anatomical variation seems to be correlated with a gradient of decreasing temperature and aridity, and increasing elevation. The anatomical variation corresponds with variation in the biochemical production. The numerical classification of ali characters indicates a rather isolated position of the population which occurs in xerophytic plant associations at low altitude.
Caryological and morphological analyses were conducted on Viola tricolor subsp. subalpina and on a zinc violet from the Western Julian Alps, described as Viola tricolor subsp. subalpina var. raiblensis var. nova. Both taxa, which have different ecology and distribution, have 2n = 26 chromosomes. Caryotypic evolution in the zinc violet mainly involves changes in absolute chromosome size and in centromeric and relative size simmetry in respect with var. subalpina, from which it appears to have evolved.