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Stipa pennata and its Companions In the Flora of VastergotlandBy LENNART FRIDENThe province of Vastergotland in the south-west ofSweden has a variable nature with many types oflandscape. In particular the Cambro-Silurian areasare characteristic: The hills of Halleberg and Hunnebergto the west and Kinnekulle on Lake Vanernto the north, each with a cap of diabase, and athird, large area in the centre of the province(MUNTHE 1906, geological map). This latter area hasthe shape of a triangle, the northern tapering partof which includes the large table-hill of Billingenwith its flat diabase plateau and its surroundingslopes. Its southern broader part comprises theelevated area known as Falbygden and resting onhorizontal Ordovician limestone. In his Wastgotaresa1747 LINNlEUS says "that the Falbygden isthe same as the alvar of bland although Falbygdenhas some more soil upon it" (transl.). Adeep depression running north-south-the Aslevalley-dissects the limestone plateau into twoparts, the West and East Falbygden. On each occursa row of table-formed hills. There is a famousview from the southernmost and highest of the"Vastgota hills", the Alleberg. It reaches 334 m,being about lOO m above the surrounding plain.The Falbygden area is known for its rich andinteresting vegetation (ALBERTSON 1951 a, etc.).There are several series of slopes from the calottesof diabase on the hill tops all the way down intothe Asle depression or down to Archaean surroundingsat lower levels. We find here rich groves,meadows and fens on flushed substrates rich innutrients. The details of the landscape are to someextent of Quaternary origin. The Quaternary historyin this area is quite complicated owing to oscillationsin the position of the front of the melting inlandice. The:.. 'e are end moraines, glacifluvialplateaux and eskers, but small parts of the horizontalplanes are deficient in soil and similar toalvar areas. These alvars in miniature-in additionto the heath of Osterplana on Kinnekulle-are theonly ones on the Swedish mainland (ALBERTSONl946a). Thus there are edaphic conditions favourablefor the formation of calciphytic heaths anddry meadows of a somewhat steppe-like appearance.An interesting feature in the flora of Falbygden isthe encounter of several different elements. Bothpronouncedly northern and markedly southern orsouth-eastern species are members of the vegetation.Among the former we mention Poa alpina as typicalof the alvar heaths, Saussurea alpina (FRIDEN1954), Selaginella selaginoides ( ALBERTSON 1942 b)and Saxifraga hirculus (ALBERTSON l946b, B. M. P.LARSSON 1959a, ALBERTSON & B. M. P. LARSSON1960, FRIDEN 1959b) and the moss Rhytidiurnrugosurn (ALBERTSON 1940a). Among the southeasternspecies the most remarkable is the feathergrassof the steppes, Stipa pennata, here referableto its ssp. Joannis (see HYLANDER 1953, p. 216).The occurrence of the feathergrass in Falbygden ishighly disjunct, being a distant north-western outpostfrom a Continental European area. The closestoutpost is in middle Germany. Great interest isassociated with other steppe species, too, membersof the Stipa community, e.g. Galiurn triandrurn(Asperula tinctoria), Polygala comosa and Dracocephalurnruyschiana. In the following some problemswill be dealt with regarding the occurrence ofStipa in Falbygden. But first a few words on thehistory of discovery of this species.DISCOVERY AND REDISCOVERIES.-Stipa pennatawas discovered about 1760 by a pupil of LINNlEUS,J. P. FALCK, later to become professor in St. Peters-Acta Phytogeog.r. Suec. 50