192 GLOSSARY. 
Segment. One of the parts of a gamopetalous corolla or gamo- 
sepalous calyx: one of the parts of a lobed leaf. 
Sepals. The outer, or only, series of floral leaves, constituting 
the calyx; sometimes (clematis) petal-like. 
Seriate. In lines or series, as applied to ducts in cross section 
of wood. 
Serrate. Toothed, with the teeth pointing in one directign like 
those of a saw: double serrate leaves have such teeth again 
serrate: contrasted with crenate and dentate. 
Serrulate. Very finely serrate. 
Sessile. Not stalked. 
Shaling. Scaly, in large flakes (bark of shag-bark hickory). 
Shredding. Falling away in shreds (bark of the grape vine). — 
Simple. Of a single leaflet, as applied to leaves: unbranched, | 
as applied to stem or inflorescence. 
Single. With the normal number of showy parts, as applied to 
flowers: contrasted with double. 
Sinus. The notch between two lobes. 
Smooth. Not roughened: frequently, but less accurately, also 
used in the sense of glabrous. 
Soft-wood. Technically the lumber derived from conifers. 
Solitary. Applied to buds when only one occurs at a node: -° 
contrasted with the cases in which there are more than one, 
either collateral or side by side (oak, maple), or superposed 
one above the other (walnut, honeysuckle). pe 
Spatulate. Oblong with the upper part rather abruptly widened. 
Species. A natural group of plants composed of individuals; 
often comprising several minor forms,—subspecies or var- 
ieties. Specific names, when not substantives in apposition 
(Acer Negundo) or in the genitive (Viburnum Carlesii), 
agree in number and gender with the name of the genus 
(Quercus alba, Calycanthus floridus, Viburnum nudum). 
Spermatophytes. Seed- or flowering-plants. 
Spike. A simple elongated compact cluster of flowers or 
sporangia. 
