Édouard Pynaert was a professor at the Ghent horticultural school (Bulletin of the Société Royale Linéenne de Bruxelles, vol. 3, p. 71), garden architect (see cover of his 1871 book Éloge de Van Mons), and apparently specialized in Pomology (see Illustration Horticole, vol. 19, 1872, p. 298).
Journal des Roses - Avril 1878 p.48 advertisement by Joseph Schwartz nursery
EDOUARD PYNAERT, Rosier vigoureux à rameaux droits, feuillage d'un beau vert foncé, pédoncule ferme et d'une tenue parfaite, fleur grande, pleine, globuleuse, coloris d'un beau rouge groseille vif, bord dos pétales légèrement carminé. — Cette plante, de premier mérite, franchement remontante, est issue de la variété Antoine Ducher.
Approx. translation, please feel free to improve :-) Vigorous rose with upright stems, lovely dark green foliage, firm peduncle, large flower, full, globular, beautiful bright red currant shade, edge of petals, slightly crimson This plant, of first merit, is "frankly" Remontant and is derived from the cultivar Antoine Ducher.