R. bourgeauiana (Species) = R. acicularis var sayiana Ehrlanson. The rimmed hips suggest that these pictures are of R. Sayi Schwein.

Papers Mich. Acad. Sci. Arts & Letters 5: 77-94 (1925)
Mackinac Wild Roses
Eileen Whitehead Erlanson

Rehder in establishing the name R. acicularis var. Sayi does not cite R. Sayi Schweinitz as a synonym. If he did, it would be technically justifiable to use Rehder's combination, even though it were impossible to place under it the round-hipped plants which he describes. It would likewise be in order to disregard the synonym which he does cite: R. acicularis var. Bourgeauiana. Since he does not cite Schweinitz's name, the only solution of the difficulty seems to be to make a new varietal name. Rehder's varietal name has to be interpreted by the description and by the synonymy he does give, rather than by the implied synonymy. It is here treated not as a synonym of R. Sayi Schwein., but rather of R. Bourgeauiana.

North American Wildflowers (1925)
Mary Vaux Walcott