HORTICULTURAL SOCIETY. 193 



glass, it will be seen that it contains little flowers within — each one 

 composed of fine stamens with their anthers united, forming a cyl- 

 inder around a two-branched style. It also has a corolla, tubular 

 and fine toothed. The head of florets is surrounded with a scale- 

 like involucre, and rays, which are analogous to the calyx and 

 petals of a single flower. 



A majority of the composite do not bloom until near autumn; as 

 if their complex nature required a longer time to mature, than the 

 more simple flowers. They are more abundant in tropical coun- 

 tries than in the temperate region. One tenth of the whole vege- 

 table kingdom belongs to this order, yet in tropical America, one 

 half is the proportion. 



We can mention but few of the one hundred species of compos- 

 itae growing wild in Minnesota. Many of the most common flowers 

 belong to the genera Aster and Solidago. It will be a satisfaction 

 if I can describe the genera of these, so that any one can easily 

 classify them. As for species, that would be rather difficult. 



Aster. These are the distinguishing features of the genus 

 Aster: The ray flowers are perfect, that is, with stamens and 

 pistils, rays in a single series always white, purple or blue — never 

 yellow. The disk is often yellow, changing with age to purple. 

 The receptacle is always flat, with a honey-comb appearance. 

 The seed-covering — achenium — is more or less flattened. 



One of the most easily distinguishable species is the aster seri- 

 ceus, found on our dry, sandy Minnesota prairies, with solitary 

 bright blue heads, silvery leaves, with an involucre similar to the 

 leaves. Another is the Aster azureus. Hays bright blue, lower 

 leaves on long petioles, hear -shaped at the base, and upper leaves 

 lanceolate linear and sessile on the branches, oval shaped. 

 Aster multiflorus has numerous small, white flowers; stem 

 crowded with small linear leaves. 



Solidago. Golden rod. During the past year or two there has 

 been a spontaneous determination on the part of the people of the 

 United States to establish the golden rod as the national flower of 

 the Union. The genus solidago has all yellow flowers, except one 

 species ; leaves alternate ; never lieart shaped ; heads of flowers 

 small, with from one to fifteen small pistillate rays; stem erect, 

 branching near the top. Minnesota is brilliant with golden rods 

 in September. One of the most prominent is the solidago rigida. 

 It is known by its rough rigid leaves, and heads of flowers clus- 

 tered into a flat topped corymb; two or three feet high; each head 

 contains about thirty-four flowerets. S. serotina — "smooth golden 

 rod," grows very large in this state on the bottom lands. 8. Can- 

 adensis is fonnd on the borders of thickets and fields. It is 

 ditiuguished by its many small heads in one sided racemes. The 

 whole plant is somewhat downy. 



Sunflower. The sunflowers are distinguished by the yellow 

 neutral rays — a four-sided and laterally compressed achenium, 

 which is neither winged nor margined, with two thin chaffy awned 

 scales on its principal angles. 



Helianthus rigidus,grows about three feet high, has many thick 



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