MALLOW FAMILY 



MALVACEAE 



PRICKLY SIDA 



Sida spinosa L. 



The specific name of this plant comes from the occur- 

 rence cf a little pointed tubercle at the base of each of the 

 larger leaves, but it is somewhat inept, for this protuber- 

 ance, though solid, can hardly be 

 called a spine and the plant is not 

 really prickly. 



The Prickly Sida is native 

 throughout tropical America and has 

 spread northward to Maine, Michi- 

 gan, southern Wisconsin 

 and Iowa. It is the only 

 Sida in Illinois. It is a 

 much branched, finely 

 and softly hairy annual 

 which grows i-2 feet high 

 and produces small yellow flowers all 

 summer. 



The flowers open for only a few 

 hours in the morning. The calyx is 

 5-toothed and naked at the base; 

 that is, there is no involucel. The 

 corolla consists of 5 yellow petals 

 which are usually slightly i -sided 

 but entire. The numerous stamens 

 form a column which bears anthers 

 only at the top. There are 5 pistils 

 grown together to form a compound ovary but the 5 styles are 

 distinct. The 5-parted fruit is within the persistent calyx and 

 each part splits at the top into 2 beaks so that the fruit becomes 

 lo-beaked. Each division of the fruit contains i seed. 



The Poppy Mallow, Callirhoe involucrata (T. & G.) Gray, is a 

 diffuse spreading herb of sandy areas, blooming from April to August. 

 Its palmately 5-9-lobed leaves, with conspicuous, ovate, persistent 

 stipules, are alternately arranged and on medium, long-haired 

 petioles. The hairy upper stems and branches end in long hairy 

 peduncles terminated by solitary red-purple flowers 1 inches in 

 diameter. Sepals and petals are 5, and the pistils are indefinite. This 

 is a common annual weed from Massachusetts to Michigan, Kansas 

 and southwestward. 



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