This section is from the book "An Illustrated Flora Of The Northern United States, Canada And The British Possessions Vol2", by Nathaniel Lord Britton, Addison Brown. Also available from Amazon: An Illustrated Flora of the Northern United States, Canada and the British Possessions. 3 Volume Set..
A. Collinsii Fernald, Rhodora 7: 31. 1905.
Perennial, similar to Arabis Holboellii, but the basal and lower leaves are finely and densely stellate-pubescent. Stems slender, 1° high or less, erect, glabrous and glaucescent above, densely pubescent near the base; basal leaves oblanceolate to obovate, petioled, tufted, 1/2'-1' long; stem-leaves lanceolate, acute at apex, sagittate at base; flowers 2"-2i" long; fruiting pedicels 2 1/2"-4" long, strongly reflexed; pods linear, 1'-1 3/4' long, about i" wide, acute or acutish; seeds narrowly winged above, in 2 rows in each cell.
On dry limestone rocks, Rimouski County, Quebec. June-July.