DOGBANE FAMILY 



APOCYNACEAE 



AMSONIA 



Amsonia T abernaemontana Walt. 



Nearly all members of the Dogbane family have an acrid 

 milky juice which in some species is extremely poisonous. 

 Familiar cultivated plants belonging to this family are the 



Oleander and the Peri- 

 winkle or Myrtle. The 

 Dogbane has that name 

 because at one time it was 

 thought to be poisonous 

 to dogs. 



The Amsonia is a south- 

 ern plant, abundant in the 

 Ohio river valley and in- 1 

 creasingly rarer to its north- 

 ern limit in Illinois — Ful- 

 ton county. It grows in 

 moist soil in open places 

 from New Jersey to south- 

 ern Illinois and Missouri, 

 south to Florida and Texas. 



It is a perennial herb 

 with alternate membran- 

 ous leaves and rather large 

 blue or bluish flowers. The 

 stem is smooth or nearly so, 

 2-4 feet high and simple or 

 branched above. Leaves vary from ovate to lanceolate and 2-^ 

 inches in length, but are always entire and sometimes hairy 

 beneath. 



The numerous flowers are produced from April to July. The 

 calyx is 5-parted, the segments narrow and pointed. The corolla 

 has 5 linear lobes as long as the cylindrical tube, which is some- 

 what enlarged at the top and lined with soft hairs. The 5 short 

 stamens are inserted in the throat and do not extend beyond the 

 tube. There are 2 ovaries with their styles united. The rounded 

 stigma is surrounded by a cuplike membrane. The fruit consists 

 of a pair of cylindrical, several-seeded follicles 2-4 inches long 

 and smooth. The seeds are also cylindrical or oblong and some- 

 what rough but without appendages. 



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