12 Addisonia 



recent years. It grows in Florida from Soldier Key up the coast to 

 Baker's Haulover about opposite Arch Creek on the mainland. 



Like the peanut of commerce (Arachis hypogaea), the dune- 

 groundnut buries its flower in the sand and matures its fruits usu- 

 ally four to six inches under the surface. A young plant arises 

 from each fruit as a tuft of leaves with a large deep rose-purple or 

 nearly blue flower. Branches arise from the tuft of leaves, often 

 a dozen or sometimes more. These radiate from the original root 

 and grow to a length of two to six feet or more, and flowers are borne 

 at each node of the branches and branchlets; the earlier are larger 

 than the later ones. 



Not only is the plant conspicuous on account of its bright colored 

 flowers, but the leaves, bright green above and silvery-green be- 

 neath, make a strong contrast with the sand in which this plant 

 grows. The plant up to the calyx is clothed with clammy- viscid 

 hairs. When the loose sand in which it grows is blown over it, all 

 parts are clothed with the fine grains, which in this case are not 

 siHca, but small fragments of sea shells which have been ground up 

 by the surf of the adjacent shore. 



The dune-groundnut is very beautiful for a part of each year. 

 There seems to be no regular season for it, plants and colonies ap- 

 pearing according to the times the fruits ripen and the local condi- 

 tions favorable to their sprouting. Although this plant looks as if 

 it were a perennial, it really is an annual and when its season is past 

 and the leaves have disappeared, there remains a tangled mat of 

 brown branches and branchlets in place of the former beautiful 

 ground cover of green leaves. The specimen from which the ac- 

 companying illustration was made was collected by the writer on 

 the sand-dunes near the ocean about seven miles north of Miami, 



April 30, 1918. 



John K. Smai,i,. 



Explanation of Platb. Fig. 1. — Portion of stem, with flowers and fruit. 

 Fig. 2.— Portion of flower, X 2, 



