Book  (1936)  Page(s) 295.  
 
Germanica var. B (hybrid rugosa) Dr. Müller 1890 or 1902; violet-red

Book  (1902)  Page(s) 146.  
 
R. Rugosa. Race de Rosiers RUGUEX du Japon.
5406. Germanica, var. B (Dr. Müller 1900), violet rouge

Magazine  (1895)  Page(s) 75.  
 
Forms and hybrids of Rosa rugosa
Mr. Court Marshall v. St. Paul in Fischbach collects all rose varieties with rugosa blood. Following varieties are in his possession to date: Rosa rugosa, Thunberg, root form; Rosa rugosa alba, Rosa rugosa rosea, Kaiserin des Nordens (Regel from Japan '75), Rugosa germanica (Dr. Müller), Rugosa germanica lighter form, Compte d'Epremesnil (Nabonnand '82), Mme Georges Bruant (Bruant '88), Mme Charles Fredr. Worth (Schwartz '90), Thusnelda (Dr. Müller '89), sport of Thusnelda, Rugosa fimbriata (Morlet '92), El Mikado (from Japan?), Zuccariniana (Bruant), ugly; America (Paul and Son '94), Cöbler (Dr. E. Kaufmann '93), Jelina ibid, Tamogled ibid, Vihorlat ibid, Hargita ibid, Belle Poitevine (Bruant '94), Calocarpa ibid, Souvenir de Christophe Cochet (Cochet-Cochet '94), Blanc double de Coubert (Cochet-Cochet '92), Parnassina (Cochet), Microcarpa (T. Smith), Rugosa splendens (T. Smith), Rugosa alba microphylla (T. Smith).
Unissued seedlings have Dr. Müller, Dr. Kauffmann, P. Lambert and myself. Perhaps also Mr. Dawson (although he doesn't say it) another American, whose name I currently cannot remember, but who is an editor of "Rural New-Yorker". von St. Paul.

Magazine  (1894)  Page(s) 74.  
 
Rugosa Germanica. Seedling of Kaiserin des Nordens, originated at Dr. Müller, much better than the mother.
Also its sister, well double, but of matte bluish pink colouring.

Magazine  (1890)  Page(s) 27.  
 
[From "Rosa rugosa" by Dr. Müller]
...Rosa rugosa flore pleno, the so-called Kaiserin des Nordens....Forstmeister Geschwind states in The Metz'schen Rosenzeitung, October issue 1888, that it is sterile and has set fruit with him.
I do not make crossing trials with this rose, and although I never saw fruit prior or later on it, in summer 1886 a strong shrub of this sort produced two chance fruit on a bloom cluster of the second bloom. These contained six or seven of the beautiful smooth seeds characteristic for the species. Placed in a container in November, some germinated in spring 1888 [1887?]. Although I neglected them - with no expectations - there were still two plants in autumn, which I planted in the garden because of their beautiful foliage. They passed the winter - only covered lightly with sand - without problems and developed in summer 1888 to low bushes with a great tendency to suckering. In August 1888 I grafted one of these plants, the one larger and with more beautiful foliage, on the rootstock of six canina seedlings. All grafted plants grew well and attained in 1889 a height of 50-60 cm; on each plant developed very double, fragrant, over medium size blooms which looked like carnations in the early phase of expansion, and in colour similar to the seed parent. The duration of the bloom was about a week, the bushes did however not repeat in their first year.
As this seedling is very distinct from the mother by its bloom, but also by its larger, dark green, glossy foliage, we can assume rightfully that Rugosa fl. pl. is a hybrid, whose new seedling reverts back in habit and foliage to the species.
I have this summer grafted a larger number of understocks with them and will be able to give a better opinion in summer 1890 on this interesting seedling of Rugosa fl. pl.