A tuberous herb of the family Asteraceae, containing
some twelve species native to Latin America, the dahlia was
discovered by a botanist who travelled with Spanish conquistadors
in the 16th century in Mexico, when he happened upon the tree
dahlia, with its flowers, open center and single blooms with
pendant stems and which had been named by the Aztecs "acocotli"
(water-cane") because they used the stems, sometimes over
twenty feet long, for hauling water. The botanist named the
tree _dahlia imperialis_ but, despite the imperial name, it
was two centuries before the seeds were transplanted to Europe,
and then the Europeans were more interested in eating the tubers
of the dahlia than in its undistinguished blossoms. Only in
the 18th century, when double formed dahlias began to be developed,
did dahlias become popular, and then there was much interest
in developing various combinations of color, until the possibilities
became exhausted, and the love of dahlias waned. An accident
or act of fate, it is always hard to tell which, caused a box
of dahlias to be sent back to Mexico from Holland in 1872. All
the dahlia tubers died but one, and that one bloomed with a
brilliant red with petals, or as they are called in dahlias,
ray florets, that rolled back and pointed. Thousands of varieties
were developed, and the sizes range from Giant to Pompon, and
there are eighteen classifications of dahlias based on the form,
largely dependent upon whether the ray florets are flat, revoluted,
twisted, curly, wave, broad at the base, incurved, recurved,
split or lacinated, fully doubled, partially doubled, open centered,
with a fully doubled center, fringed, ball-shaped, though the
desired shape of the dahlia is the shape of the globe, they
are not called so much flowers, as flowering heads, for this
reason, they may be said to be associated with the "third
eye" and are the official flower of Mexico.