Plant-Structure 



A staminate flower has stamens, but no pistil ; a pistillate 

 flower has pistil, but no stamens ; this form of growth prevails in 

 the catkin-bearing (amentaceous) trees and shrubs ; sometimes 

 the two forms grow on the same plant ; sometimes only the stami- 

 nate on one, the pistillate on another, as in the ailanthus. 



ARRANGEMENT OF BLOSSOMS 



Blossoms grow either suigly or in clusters. Clusters are of 

 different forms : 



An UMBEL contains few or several blossoms, whose separate 

 stems grow from almost the same point on the branch, as in 

 cherry or apple-tree (Fig. 14). 



A RACEME is a slender, leafless, unbranched stalk, bearing 

 numerous blossoms (with stems) throughout its length (Fig. 15). 



A SPIKE is a raceme densely crowded with minute stemless 

 blossoms (Fig. 16). 



A PANICLE is a leafless branching stem covered with blossoms ; 

 in other words a compound raceme : both raceme and panicle 

 commonly bear the rudiments of leaves, often called bracts : a 

 leafy raceme has the leaves somewhat developed (Fig. 17). 



A CORYMB is a raceme, in which the lower flower-stems are Ion- 

 ger, producing a flat-topped or convex cluster (Fig. 18). Com- 

 pound corymbs and cymes often have an immense number of 

 blossoms, as in the hydrangea and hobble-bush. 



A CYME is much like a corymb, flat-topped or convex, but the 

 middle flowers developing first. 



A HEAD is a dense spherical mass of small blossoms (Fig. 19). 



A CATKIN or AMENT is much like a spike, but the blossoms 

 are very rudimentary, having no corolla (sometimes no calyx), 

 staminate and pistillate, and 1-4-clustered, each cluster under a 

 scale or minute bract, and crowded on the stem (Fig. 20). Cat- 

 kins are usually /i?«^i?;z/, spikes erect. 



A CONE is a longer or shorter (occasionally spherical) growth, 

 covered with broad, flat, rigid scales against which (with no cov- 

 ering) lie the seeds (Fig. 21). 



Blossoms (single or clustered) are terminal or lateral, accord- 

 ing as they are borne at the end of the branch, or along the side. 

 417 



