1. Spinacia oleracea Linnaeus, Sp. Pl. 1027. 1757; Kom., 1.c. 75, P1. 11 fig. 7; R.R. Stewart, Ann.Cat.Vasc.Pl.W.Pak.Kashm.227.1972; Uotila. l.c. 62.
S.spinosa Moench., Meth. 318. 1794; S.glabra Mill.., Gard. Dict. ed. 8 (2): 1768; S.tetrandra auct. non Stev. (1809); Roxb., F1. Ind. 3: 711. 1824.
Annual or biennial, dioecious herb, 20-60 cm tall, erect, light green, glabrous. Leaves ovate to triangular-hastate, entire or dentate, lower long-petiolate, usually entire, Staminate flowers in interrupted spiciform panicles, with 4 (-5) perianth segments and stamens; pistillate flowers in dense axillary sessile clusters, each separated and falling so in fruit; bracteoles in fruit orbicular-obovate, usually broader than long, free, with (f. spinosa) or without (f. glabra) divergent spines at the apex.
Fl. Per.: Feb.-May.
Lectotype: Herb. LINN.-1174.1 microfiche! (Hedge in Regnum Veg. 127: 90. 1993).
Distribution: Probably originated from S.tetrandra Stev. in W. Asia.
Spinach is widely cultivated and sometimes naturalized or found as an escape from cultivation; leaves are commonly used as vegetable. It contains a considerable amount of vitamins A, B and C, iron and phosphorus and sufficient protein inferior only to meat; and thus an important food for weak and anaemic persons; it is said to increase secretions of stomach and function of pancreas.