Jones: Flora of Illinois 281 



if differentiated; the strap-shaped part of the corolla of the ray-flowers in 



Compositae. 

 Receptacle. The more or less expanded portion of an axis bearing the organs of a 



flower or the collected flowers of a head. 

 Regular (flower). See Actinomorphic. 

 Remform. Kidney-shaped; having the width greater than the length, and a wide 



sinus at the base. 

 Repand. With a slightly sinuate margin. 

 Reticulate. Net-veined; like a network. 

 Retrorse. Turned backward or downward. 

 Retuse. Slightly notched at the rounded apex. 

 Revolute. Rolled backward from the margin or apex. 

 Rhizome. A more or less elongated, usually underground, horizontal or ascending stem 



modified for food storage and asexual reproduction. 

 Rhombic. Having the shape of a rhomb; oval, but somewhat angular at the sides; 



obliquely four-sided. 

 Rotate, (corolla). Wheel-shaped; with a flat and circular limb, and a very short tube. 

 Rugose. Wrinkled. 

 RuGULOSE. Minutely rugose. 

 Runcinate. Pinnatifid; cut into sharp triangular lobes, the points directed backwards. 



Sagittate. Shaped like en arrowhead, with the basal lobes directed downward. 

 Salverform (flower). With the slender corolla-tube abruptly expanded in a flat limb. 

 Samara. A dry indehiscent, one-seeded, winged fruit, such as that of elm, ash, or 



maple. 

 SAPROPH'iTE. A plant which derives its food from non-living organic matter. 

 ScABRELLOUS. See Scabrid. 

 ScABRID. Slightly rough to touch. 

 Scabrous. Rough to the touch. 



Scale. A term applied to several kinds of small usually appressed leaves or bracts. 

 Scape. A leafless peduncle arising from the ground; it may bear scales or bracts but 



no leaves and may be one- or several-flowered. 

 Scapiform. Scape-like; having the form of a scape. 

 ScAPOSE. Having a scape. 



ScARlOUS. Dry, thin, scale-like; membranous; not green. 

 ScORPlOlD. Applied to inflorescences which are circinately coiled in the bud, unrolling 



as the flowers expand, as in some Boraginaceae. 

 Secund. Turned to one side, as the flowers of an inflorescence. 

 Sepal. One of the parts or lobes of a calyx. 

 Septate. Divided by septa, or partitions. 

 Septicidal. Dehiscing along or in the partitions; said of a fruit that opens between the 



locules. 

 Septum. A partition. 



Sericeous. Silky; pubescent with soft, shining, usually appressed hairs. 

 Serrate. Saw-toothed; having small, forwardly-directed sharp teeth en the margin. 

 Serrulate. Finely serrate. 

 Sessile. Not stalked. 

 Setaceous. Bristle-like. 

 Setose. Beset with bristles. 

 Setulose. Finely setose. 

 Sheath. The basal part of a leaf of a grass; any long and more or less tubular 



structure surrounding an organ or part. 

 Shrub. A woody plant which does not become tree-like and usually produces several 



stems from a common base. 

 Simple (leaf). With the blade all in one piece; not divided into separate leaflets. 

 Sinuate. With a strongly wavy margin. 



SoRUS. One of the fruit-dots or clusters of sporangia on the leaves of ferns. 

 Spadix. a thick or fleshy spike of certain plants, as the Araceae, surrounded or sub- 

 tended by a spathe. 

 Spathaceous. Resembling a spathe; spathe-bearing. 



