F.C. Stern A Study of the Genus Paeonia

28. P.rhodia W. T. Stearn sp.nova, in Gard. Chron. 1941 ; F. C. Stern in Journ. Roy. Hort. Soc. 68, 127 (1943).

Description, Stem glabrous, reddish, 28 to 35 cm. high. Lower leaves biternate, with all or nearly all leaflets divided; terminal leaflet of each set of 3 trifurcate, lateral leaflets usually bifurcate, sometimes entire and sometimes divided into 3 or 4 ; leaflets entire, narrowly oblong-elliptic, apex acute or acuminate, base cuneate and sometimes confluent to the stem, thin and papery, 2.5-3 cm. long and 7 mm. to 3-7 cm. wide, green above, pale green beneath, quite glabrous, shortly petiolulate, sometimes almost sessile. Flower about 7 cm. across, petals white obovate to broadly obovate. Stamens about 1.5 cm. long, filaments red, anthers yellow. Carpels 2 or 3, pubescent, with hairs white or flushed with red. Follicles 2-2-5 cm. long.

Distribution. island of rhodes (K) : Mt. San Elio, near Salakos, Bourgeau (K); Mt. Profitze, Engelhardt (K).

Specimens of a paeony species found so far only on the Island of Rhodes are at the Kew Herbarium. This paeony, raised from seed collected on the Island of Rhodes, has been cultivated in gardens by Mr. E. A. Bowles at Enfield, Mr. C. Woodward at Bewdley and the late Mrs. Landby, who collected seed on Mount Profitze. The plant of Mrs. Landby was examined by Mr. L. F. La Cour of the John Innes Horticultural Institution, who determined it as a diploid.

W. T. Steam has described it as a new species, with the name of P.rhodia. The diploid character is extremely interesting as here again is a diploid paeony species confined to an island in the Mediterranean. P.rhodia reminds one at first of a poor and immature specimen of P.arietina var. orientalis but it differs from it in the larger number of leaflets, and in their being thin and papery but resembles it in the shape of the leaflets and in being glabrous except for the carpels. The number of leaflets is an unusual character of this species. W. T. Steam, who examined specimens at the Natural History Museum at Vienna, reports that there are specimens of a lower leaf with 30 leaflets formed by the division of the lateral or/and terminal segments. This character is somewhat reminiscent of P.Broteri, the diploid species from southern Spain and Portugal. It is easily distinguished from P.Broteri, whose leaflets are thick and elliptic while the leaflets of this species are thin, papery and narrowly oblong-elliptic.

P.arietina is a tetraploid with a wide distribution from Italy to Armenia but the chromosome numbers of the glabrous form P.arietina var. orientalis found in Syria, Cyprus and Crete are not known. P.rhodia might be the diploid species from which P.arietina and the glabrous variety were derived.

This paeony is not a robust plant and is difficult to cultivate.

Mr. G. Woodward ofArley Cottage, near Bewdley, has grown P.rhodia in his garden and flowered it in the middle of May. Mr. E. A. Bowles of Myddelton House, Enfield, writes : " the Paeony from Rhodes will start into growth in November and is now (June) dying down. Dr. F. Crane, Professor of the Johns Hopkins University, U.S.A., sent me scraps of root and the previous year's seed and a flower from Rhodes some dozen years ago. All I have tried in the open perished, cut down by frost." [end page 84]