The Book of Roses (1838)
Rosa Alba and two "varieties"
Mrs Gore (trans. from Boitard)

Having now passed in review the specific characters of each several organ of the plant, and proved that nearly all are uncertain and inauthoritative, we will present a table of comparison, showing the distinctions between the Rosa alba and the Cuisse de Nymphe, one of its varieties; and in addition, (to avoid the inference that hybridity may have been the origin of the discrepancy,) we subjoin the Placidie, (of Vibert,) created by Monsieu Prevost, jun., by fixing, by graft, a variety accidentally produced on the branch of a Cuisse de Nymphe.

Rosa Alba Cuisse de Nymphe Placidie
Branches, vigorous, spreadingBranches, vigorous, spreadingBranches, slight, vertical
Thorns, straight, weakThorns, strong, crookedThorns, scarcely any
Leaflets, large, almost round, glaucousLeaflets, oval, pointed, large, pale greenLeaflets, small, straight, dark green; never glaucous
Flowerstalk, hispid, with weak irregular thornsFlowerstalk, strong, hispid above the stipules, smooth belowFlowerstalk, thin and smooth
Tube of the calyx, oval, distaff-shaped, hairyTube of the calyx, short, hairyTube of the calyx, narrow, never hispid
Sepals, pinnated, longSepals, pinnated, longSepals, short and close
Petals, concave, emarginatedPetals, concave, emarginatedPetals, undulating, and globulous
Flowers, large, white, singleFlowers, middle-sized, very double, flesh-colour, paler at the edgeFlowers, small, semi-double, of a brilliant and uniform pink

In the foregoing table, we have instituted a comparison between two varieties, and their parent species. Varieties, differing far more extensively from their original type, might have been selected for the purpose; but we prefer the white rose and its varieties, on account of the Placidie being literally only a detached branch of the Cuisse de Nymphe.

CybeRose comments: This discussion was an attempt to prove that many characters that have been used to distinguish species are too variable to be so used. However, Boitard overlooked the possibility that Cuisse de Nymphe was itself a hybrid of Rosa alba rather than a "pure" variety.

Whatever the origin of Cuisse de Nymphe, the sport Placidie raises some interesting questions about the hereditary potentials of its parent. It is highly doubtful that a single gene mutation could produce all the distinguishing characters of Placidie.