Euphrasia arctica subsp. borealis, (Townsend) Yeo

Tutin, T. G., Heywood, V. H., Burges, N. A., Moore, D. M., Valentine, D. H., Walters, S. M. & Webb, D. A., 1972, Flora Europaea. Volume 3. Diapensiacea to Myoporaceae, Cambridge: Cambridge University Press : 262

(d) Subsp. borealis (Townsend) Yeo , op. cit. 358 (1971)

(£. rostkoviana f. borealis Townsend , E. brevipila auct., non Burnat & Gremii):

Stem with 0-5(-6) pairs of usually long, erect or ascending branches. Cauline internodes 2-4(-7) times as long as leaves. Lowest flower at node 4-8(-10). Leaves often with short, and occasionally with long glandular hairs, the cauline 3-14 mm, ovate to oblong, the lower floral (4-)6-12(-14) mm, ovate to deflate, rounded to subcordate at base, with (3-)4-6(-7) pairs of subacute to acuminate teeth usually much longer than wide. Corolla 6-9(-10) mm. Capsule 4-7 mm, usually not exceeding calyx, at least twice as long as wide, elliptical to oblong. 2« = 44. Britain and Ireland; W. Norway.

Plants resembling 11(d) found in N.E. Europe are probably hybrids between 11(a) and 17.