Structure, etc., of Epiphegus Virginiana. 355 



of it are numerous bracts or scale-leaves. These are small 

 yellow-white, reddish or brown reduced structures. 



Above the tuber rises the aerial stem, which is merely the 

 axis of inflorescence. It rarely remains simple, more com- 

 monly it branches, and continues branching freely through 

 most of its upward course. It shows a nearly constant tor- 

 sion from left to right. This torsion is made evident in the 

 grooves passing down below each of the flowers, and in 

 the lines of darkened color occurring frequently along the 

 stem. Both stem and branches are remarkably stiff, inflexi- 

 ble, unyielding structures. They are of a reddish or dull 

 tawny brown color, and show streaks of darker brown, white 

 and purple. The branches always arise in the axil of a 

 bract. Some may arise separately on the tuber itself. Along 

 the aerial stem and its branches appear the small bracts. 

 They are arranged in a two-fifths spiral, sometimes in a 

 three-eighths spiral; but in the upper part of stem and 

 branches they seem to lose all regularity of position. In the 

 upper part of the tuber these bracts are found, each sub- 

 tending a small swelling or papilla. These swellings prob- 

 ably represent abortive branches. Bracts even occur on the 

 lower part of the tuber between the outgrowing roots. 



Throughout the greater length of stem and branches 

 flowers occur in the axils of these bracts, a single flower in 

 each axil. The total number of flowers developed on a 

 single plant is strikingly large. These flowers display two 

 distinct types — the cleistogamic or closed, and the chasmo- 

 gamic or open type ; there is frequently present a flower or 

 flowers transitional between these two. The cleistogamic 

 blooms are greatly in excess in point of numbers, they 

 mature a much greater number of seeds, and are frequently 

 the only kind of flower appearing on a plant. The chasmo- 

 gamic flowers, when present, vary in number, as succeeding 

 tables will show. When present, they occupy a limited 

 region along the upper part of stem and branches, though 

 they are scarcely ever found as the uppermost blooms. 



