180 FLOWERS 



Forms of Gamopetalous Corollas. A gamopetalous corolla 

 is rotate when it is nearly flat, as in potato; it is crateriform 

 when the united petals are saucer-shaped, as in mountain 

 laurel; it is campanulate when the corolla is rounded below, 

 longer than broad and expanded at the mouth, as in lily of 

 the valley, it is funnelform when the corolla tapers gradually 

 from the base to a broad, wide mouth, as in great bindweed; 

 it is cylindric when terete and of nearly uniform diameter, as 

 in staggerbush; it is prismatic when the corolla is angled and 

 of nearly uniform diameter, as in vaccinium ; it is saherform 

 when the corolla forms a nearly flat limb and is tubular 

 below, as in sweet William; it is urceolate when rounded 

 below and slightly constricted near the ununited, expanded 

 and recurved part of the corolla, as in bitter root; it is bila- 

 biate when there are two less ununited parts of the corolla, 

 as in wood betony; it is personate when the throat of a 

 bilabiate corolla is closed by a palate or enlargement of the 

 lower lip, as in yellow toad-flax; it is gibbous when the 

 corolla is slightly protuberant at one side, as in buttercup; 

 it is saccate when the enlargement forms a decided depression 

 or pocket as in violet; it is spurred when there is a hollow 

 or tubular extension of the corolla, as in columbine; it is 

 ligulate when the corolla is connate around the pistil, but 

 the upper part is flat and ribbon-like, as in sunflower. 



The Androecium is usually made up of two sets or circles 

 of stamens, so that normally there are as many stamens as 

 there are sepals and petals. Frequently, as in American 

 linden, one set ot stamens will divide into several so that 

 several sets appear to be present; in progressive metamor- 

 phosis change of form and function occurs, the petals chang- 

 ing into stamens, as in marsh marigold, buttercup and 

 Saint John's-wort, so that there are an indefinite number 

 of stamens. In the rose and other flowers under cultivation 



