* Scales of the receptacle awl-shaped, acute.

A. Cotula: annual; stem 1-2 feet high, branched, angular, furrowed; leaves bipinnatifid nearly glabrous, the lobes linear, acute, mostly entire; heads solitary, on long terminal stalks, the disk florets yellow, those of the ray white; involucral scales obtuse, with white membranous margins; fruit terete, tubercular-striated; whole plant fetid and acrid. - Fields and waste places. Fl. July to September.

** Scales of the receptacle thin, membranous, obtuse.

A. nobilis: stem procumbent, one foot long, much branched; leaves bipinnate, the leaflets linear-subulate, slightly downy and fleshy, acute; heads solitary, terminal, the florets of the disk yellow, of the ray white; fruit subtrigonous, smooth: whole plant pleasantly aromatic. - Chamomile. - Gravelly places. Fl. July to September.