- Missouri Botanical 
Garden Bulletin 
Vol. I St. Louis, Mo., September, 1913 No. 9 
THE PEANUT. 
In the collection of agricultural plants in the Herbaceous 
Tract southwest of the new range of greenhouses will be 
found a small plot of peanut plants. The extensive use 
of the peanut as an article of food, the value of the green 
parts for fodder, the soil enriching qualities of the roots and, 
most of all, the peculiar habit of the plant of maturing its 
seeds underground, makes it one of especial interest. The 
eanut belongs to the same family as do the beans and peas, 
Dat differs from them markedly in its habit of maturin 
the seeds underground, a fact emphasized by its technics 
name, Arachis hypogaea. It is also known under the local 
names of “goober,” “goober pea,” “pindar,’” “ground pea,” 
and “groundnut.” 
The plant is a trailing, straggling annual from one to 
two feet high with thick, hairy stems and spreading branches 
bearing orange yellow flowers in the leaf axils. hile the 
flowers are apparently stalked, closer inspection shows that 
the supposed peduncle is really only a much elongated calyx 
tube. The base of the latter fits over the small sharp-pointed 
ovary hidden among the stipules at the base of the leaf. As 
soon as pollination has taken place, the visible portion of 
the flower withers ~ at the gre time the aoe — 
eduncle supporting the ovary begins a period of rapi 
apoioien, lending downward and carrying the sharp- 
pointed ovary into the ground. The ov once buried, 
rapidly develops into the pod with its contained seeds. In 
case, however, the ovary fails to penetrate the soil, no pod 
_ develops. In brief, the peanut flowers and is pollinated above 
ground like most plants, but this accomplished the flower 
stalk quickly pushes the potential pod down into the ground 
where the pod and seeds are developed. The old idea that 
it is necessary to cover the flowers with soil is erroneous, 
though it is desirable to prepare a bed of loose soil into which 
the “pegs” can penetrate with ease. : 
(115) 
