DOGBANE FAMILY APOCYNACEAE 
AMSONIA 
Amsonia Tabernaemontana 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- 
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, 
1 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 2-5 
inches in length, but are always entire and sometimes hairy 
beneath. 
The numerous flowers are produced from April to July. The 
calyx is $-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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