346 INTRODUCTION TO BOTANY 
Antipodal (against the foot). Applied to a group of cells at the end 
of the embryo sac farthest from the micropyle. 
Apetalous. Without petals. 
Apical. At the apex or tip. 
Apocarpous (without carpels). Applied to flowers in which the car- 
pels are entirely free from one another. 
Appressed. Lying flat throughout its length, as appressed bracts. 
Association. An ecological unit group smaller than a plant forma- 
tion, of which the latter is sometimes made up. 
Awl-shaped. Narrow, tapering to a point, as awl-shaped leaves. 
Awned. Having bristle-like appendages, as in heads of many kinds 
of wheat. 
Basidium (club); pl. basidia. The specialized club-shaped cells on 
which the spores of some fungi are borne. 
Bast. The phloém portion of a fibrovascular bundle. It may be 
fibrous (hard bast), or composed of sieve tubes (soft bast). 
Bilabiate (two-lipped). Applied to the form of corolla in certain di- 
cotyledonous plants. 
Bract (a thin plate). The small, scale-like, modified leaves which 
sometimes are found at the base of the flower cluster. 
Calyptra (a cover). In mosses, the hood that covers the tip of 
the capsule. 
Calyx (a cup). All the sepals, which together form the outer enve- 
lope of a flower. 
Cambium. The meristem cells of a fibrovascular bundle lying be- 
tween the phloém and xylem, and having the power of division, so as 
to produce new phloém and xylem. 
Capitate (relating to head). (1) Rounded, as the head of the stigma 
of the primrose; or (2) growing in heads. 
Capsule (a small box). A dry, dehiscent seed vessel (formed of more 
than one carpel). 
Carpel (fruit). The megasporophyll; hence either a simple pistil or 
one of the parts of a compound pistil. 
Carpellary. Relating to a carpel. 
Catkins. See Ament. 
Caulicle (a small stem). The initial stem in an embryo. 
Cell. The morphological or anatomical unit of plant and animal 
structure. 
Cellulose (pertaining to acell). The primary substance of the cell wall. 
Central cylinder. The stele, or portion of the root or stem which is 
inclosed by the primary cortex. 
Chaff. Small dry scales usually found in connection with the seeds 
of plants, as in grasses and Composite. 
