NYCTAGINACEAF 



FOUR-O'CLOCK FAMILY 



WILD FOUR-O'CLOCK. HEART-LEAVED 

 UMBRELLAWORT 



Oxybap/ius nyctagiiieus (Michx.) Sweet 



The Four-o'clock family is a relatively unimportant 

 group, represented in our gardens by the Marvel of Peru. In 

 it the colored calyx is commonly mistaken for the corolla 

 because below each 

 flower is a green in- 

 volucre that looks 

 like a calyx. 



Several species of 

 Wild Four-o'clock are 

 occasionally found in 

 Illinois but only this 

 one is common. It 

 occurs in dry soil 

 throughout the Missis- 

 sippi basin from Can- 

 ada to Louisiana and 

 west as far as Colorado. 

 In this state it is a characteristic 

 weed of the sand or gravel beds of 

 railroads, where its red flowers are 

 very conspicuous. 



The stem, often angled or 4-sided 

 below, is rather slender, much 

 branched and 1-3 feet high. The 

 opposite leaves are smooth or nearly 



so and all are petioled except the upper bractlike ones. The root 

 is large and perennial. 



This plant blooms from May or June to August, the numer- 

 ous flowers being produced in small clusters in 5-lobed involucres. 

 The red corollalike calyx is tubular and constricted or narrow- 

 ed above the ovary. There are 3-5 stamens and i long style. 

 The fruits are i -seeded and covered with short hairs. 



The Narrow-leaved Umbrellawort, Oxybaphus linearis (Pursh) 

 Robinson, is a tall species, smooth except for the slightly hairy 

 peduncles and involucres. The leaves are thick and linear, and 

 covered with a whitish bloom. They are usually sessile or nearly so. 



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