Potentina cinerea, Chaix ex Vili.

51. P. cinerea Chaix ex Vili. , Prosp. Pl. Dauph. 46 (1779)

(incl. P. arenaria Borkh. , P. glaucescens Willd. , P. incana P. Gaertner , B. Meyer & Scherb., P. tommasiniana F. W. Schultz, P. velutina Lehm. ).

Mat-forming, with freely rooting, procumbent woody stems, and flowering stems up to 10 cm, the stem and leaves with a dense, usually continuous tomentum of stellate hairs with 15-30 rays, mixed with long, simple hairs and sometimes with glandular hairs. Leaves ternate or digitate; leaflets 3-5, 5-20 x 3-5-9 mm, oblong-obovate to broadly obovate, dentate or crenate-dentate, grey-green above, grey beneath; stipules of basal leaves linear. Flowers 1 -6. Sepals ovate or ovate-lanceolate; epicalyx-segments lanceolate or elliptical, usually shorter than sepals. Petals 4-7 mm, yellow, longer than sepals. Achenes rugose; style conical at base, slightly davate at apex. 2n — 14, 28. Dry places, up to 1600 m. C., E. & S. Europe from E. Spain eastwards; Baltic region. Al Au Be Bu Cz Da Ga Ge Gr He Hs Hu It Ju Po Rm Rs (N, B, C, W, E) Su.

Plants from Poland are sexual with 2zz = 28; this number has also been recorded from Hungary and Czechoslovakia. The chromosome numbers 2zi = 35, 42 and 56 have been found in plants from Switzerland and S. France, but it is possible that they were hybrids between 49 and 51.