A. sylvestris: stems hairy, erect, branched, 2-3 feet high; lower leaves on long stalks, twice pinnate, with ovate-lanceolate, pointed, deeply pinnatifid, toothed segments, upper leaves smaller, all hairy; umbels numerous, of 8-10 rays, without general involucre, the partial ones of several bracts; fruits smooth, shining, narrowed at the top into a short beak. - Hedges, borders of fields, etc. Fl. May, June.

A. vulgaris: annual; stems erect, branched, hairy, two feet high; leaves twice or thrice pinnate, with ovate or ovate-lanceolate, pinnately-lobed and toothed segments; umbels small, on short peduncles, opposite to the leaves, of 3-7 rays, without general involucres, and but few bracts to the partial ones; fruits covered with short hooked bristles, narrowed at top into a short smooth beak. - A weed of cultivation. Fl. May, June.