POTERIUM.] ROSACES. 129 



thin; bracteolesciliate. Stigmas exserted. Achene&ark, striate. DISTEIB. 

 Europe, N. Africa, N. and W", Asia, Himalaya. 



P. MURIOA'TUM, Spach ; flower-heads and flowers as in P. Sanguisor'ba, 

 but fruiting calyx with thick entire or toothed wings pitted and reticu- 

 lated between the wings, ridges muricate and toothed. 



Cultivated ground in Mid. and S. England; (an alien or colonist, Wats.}; fl. 

 July. Chiefly distinguished from P. Sanyuisor'ba by the larger fruit and 

 calyx. DISTJIIB. Mid. Europe and Mediterranean region. 



2. P. officina le, Hook. f. ; flowers 2-sexual, stamens 4 not longer than 

 the calyx-lobes, fruiting calyx 4-winged smooth between the wings. 

 Sanguisor'ba officinal Us, L. Great Burnet. 



Damp meadows, from Ayr and Selkirk southd. ; ascends to 1,500 ft. in 

 Yorkshire ; W. and N. Ireland ; Channel Islands ; fl. June- Aug. Very 

 similar to P. Sanguisorba, but rootstock horizontal, stem erect, leaflets 

 fewer, longer, less deeply serrate, usually cordate at the base, and flower- 

 heads often cylindric and 1-1J in. long. Flowers t honeyed, homogamous. 

 DISTKIB. Europe (Arctic), N. and W. Asia. 



11. RO'SA, L. ROSE. 



Erect, sarmentose or climbing prickly shrubs. Leaves pinnate ; leaflets 

 serrate ; stipules adnate to the petiole. Flowers terminal, solitary or 

 corymbose, white yellow or red, rarely bracteate, not honeyed, homogamous. 

 Calyx-tube persistent, globose ovoid or pitcher-shaped, mouth contracted ; 

 lobes imbricate in bud. Petals 5. Stamens many, inserted on the 

 disk. Disk coating the calyx-tube, its thickened margin all but closing 

 the mouth, silky. Carpels many, rarely few, sunk in the calyx-tube ; 

 styles subterminal, distinct or connate above, stigma thickened ; ovule 1, 

 pendulous. AcTienes coriaceous or bony, enclosed in the fleshy or coriaceous 

 calyx-tube. DISTEIB. N. temp, regions, rare in America ; Abyssinia, 

 India, Mexico ; species about 30. ETYM. The old Latin name. 



The following account of the British roses is condensed from Mr. Baker's 

 monograph (Linn. Journ. xi. 197), and revised by himself, most of the 

 species being regarded as sub-species. As with the fruticose Rubi, all the 

 so-called species are connected by intermediates ; but whereas, in the Rubi, 

 the 4 or 5 most distinct British forms are connected by so many links that 

 various botanists regard them as forms of one species ; in Rosa, the five 

 most distinct British forms are connected by so few (comparatively) 

 intermediates, that no botanical authority has reduced them to one species. 



1. R. spinosis'sima, L. ; small, erect, bushy, prickles crowded very 

 unequal nearly straight passing into stiff bristles and glandular hairs, 

 leaves not or slightly glandular, sepals more or less persistent, fruit short, 

 disk small or 0. Scotch Rose, Burnet Rose. 



Open places especially sandy sea shores, from Caithness southd. ; Ireland ; 

 Channel Islands; ascends to 1,700ft. in Scotland; fl. May- June. Shrub 

 1-4 ft., much branched. Leaves small, eglandular ; leaflets 7-9, singly or 



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