Bupleurum spinosum, Gouan

Tutin, T. G., Heywood, V. H., Burges, N. A., Moore, D. M., Valentine, D. H., Walters, S. M. & Webb, D. A., 1981, Flora Europaea. Volume 2. Rosaceae to Umbelliferae, Cambridge University Press : 349

32. B. spinosum Gouan , Obs. Bot. 8 (1773).

Intricately branched, glaucous perennial up to 30 cm; lower part of stems stout, woody, devoid of remains of dead leaves; upper parts of stems dying after fruiting, becoming hard and spinose and persisting for 2-3 years. Basal leaves linear-subulate, scarcely narrowed at base; veins 3-5, conspicuous beneath; cauline similar but smaller, few, remote. Rays 2-7, becoming rigid and spinose after the fruit has been shed. Bracts 2 mm, usually 5, subulate, 1-veined; bracteoles similar to the bracts, but sometimes lanceolate. Fruit 3-4-5 mm, ovoid-oblong; ridges filiform, prominent. S. & E. Spain. Hs.